Line 1: |
Line 1: |
| + | ==Notes Found in a Cactus Patch== |
| + | |
| + | : '''''Note.''' This is a collection of fragments from previous discussions that I plan to use in documenting the cactus graph syntax for propositional logic.'' |
| + | |
| + | ===Cactus Language=== |
| + | |
| + | Table 13 illustrates the ''existential interpretation'' of cactus graphs and cactus expressions by providing English translations for a few of the most basic and commonly occurring forms. |
| + | |
| + | Even though I do most of my thinking in the existential interpretation, I will continue to speak of these forms as ''logical graphs'', because I think it is an important fact about them that the formal validity of the axioms and theorems is not dependent on the choice between the entitative and the existential interpretations. |
| + | |
| + | The first extension is the ''reflective extension of logical graphs'' (RefLog). It is obtained by generalizing the negation operator "<math>\texttt{(~)}</math>" in a certain way, calling "<math>\texttt{(~)}</math>" the ''controlled'', ''moderated'', or ''reflective'' negation operator of order 1, then adding another such operator for each finite <math>k = 2, 3, \ldots .</math> |
| + | |
| + | In sum, these operators are symbolized by bracketed argument lists as follows: "<math>\texttt{(~)}</math>", "<math>\texttt{(~,~)}</math>", "<math>\texttt{(~,~,~)}</math>", …, where the number of slots is the order of the reflective negation operator in question. |
| + | |
| + | The cactus graph and the cactus expression shown here are both described as a ''spike''. |
| + | |
| + | {| align="center" cellpadding="6" width="90%" |
| + | | align="center" | |
| + | <pre> |
| + | o---------------------------------------o |
| + | | | |
| + | | o | |
| + | | | | |
| + | | @ | |
| + | | | |
| + | o---------------------------------------o |
| + | | ( ) | |
| + | o---------------------------------------o |
| + | </pre> |
| + | |} |
| + | |
| + | The rule of reduction for a lobe is: |
| + | |
| + | {| align="center" cellpadding="6" width="90%" |
| + | | align="center" | |
| + | <pre> |
| + | o---------------------------------------o |
| + | | | |
| + | | x_1 x_2 ... x_k | |
| + | | o-----o--- ... ---o | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | @ = @ | |
| + | | | |
| + | o---------------------------------------o |
| + | </pre> |
| + | |} |
| + | |
| + | if and only if exactly one of the <math>x_j\!</math> is a spike. |
| + | |
| + | In Ref Log, an expression of the form <math>\texttt{((}~ e_1 ~\texttt{),(}~ e_2 ~\texttt{),(}~ \ldots ~\texttt{),(}~ e_k ~\texttt{))}</math> |
| + | expresses the fact that ''exactly one of the <math>e_j\!</math> is true''. Expressions of this form are called ''universal partition'' expressions, and |
| + | they parse into a type of graph called a ''painted and rooted cactus'' (PARC): |
| + | |
| + | {| align="center" cellpadding="6" width="90%" |
| + | | align="center" | |
| + | <pre> |
| + | o---------------------------------------o |
| + | | | |
| + | | e_1 e_2 ... e_k | |
| + | | o o o | |
| + | | | | | | |
| + | | o-----o--- ... ---o | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | \ / | |
| + | | @ | |
| + | | | |
| + | o---------------------------------------o |
| + | </pre> |
| + | |} |
| + | |
| + | {| align="center" cellpadding="6" width="90%" |
| + | | align="center" | |
| + | <pre> |
| + | o---------------------------------------o |
| + | | | |
| + | | ( x1, x2, ..., xk ) = [blank] | |
| + | | | |
| + | | iff | |
| + | | | |
| + | | Just one of the arguments | |
| + | | x1, x2, ..., xk = () | |
| + | | | |
| + | o---------------------------------------o |
| + | </pre> |
| + | |} |
| + | |
| + | The interpretation of these operators, read as assertions about the values of their listed arguments, is as follows: |
| + | |
| + | {| align="center" cellpadding="6" width="90%" |
| + | | Existential Interpretation: |
| + | | Just one of the k argument is false. |
| + | |- |
| + | | Entitative Interpretation: |
| + | | Not just one of the k arguments is true. |
| + | |} |
| + | |
| + | {| align="center" cellpadding="6" width="90%" |
| + | | align="center" | |
| + | <pre> |
| + | o-------------------o-------------------o-------------------o |
| + | | Graph | String | Translation | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | @ | " " | true. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | o | | | |
| + | | | | | | |
| + | | @ | ( ) | untrue. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | r | | | |
| + | | @ | r | r. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | r | | | |
| + | | o | | | |
| + | | | | | | |
| + | | @ | (r) | not r. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | r s t | | | |
| + | | @ | r s t | r and s and t. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | r s t | | | |
| + | | o o o | | | |
| + | | \|/ | | | |
| + | | o | | | |
| + | | | | | | |
| + | | @ | ((r)(s)(t)) | r or s or t. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | r implies s. | |
| + | | r s | | | |
| + | | o---o | | if r then s. | |
| + | | | | | | |
| + | | @ | (r (s)) | no r sans s. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | r s | | | |
| + | | o---o | | r exclusive-or s. | |
| + | | \ / | | | |
| + | | @ | (r , s) | r not equal to s. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | r s | | | |
| + | | o---o | | | |
| + | | \ / | | | |
| + | | o | | r if & only if s. | |
| + | | | | | | |
| + | | @ | ((r , s)) | r equates with s. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | r s t | | | |
| + | | o--o--o | | | |
| + | | \ / | | | |
| + | | \ / | | just one false | |
| + | | @ | (r , s , t) | out of r, s, t. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | r s t | | | |
| + | | o o o | | | |
| + | | | | | | | | |
| + | | o--o--o | | | |
| + | | \ / | | | |
| + | | \ / | | just one true | |
| + | | @ | ((r),(s),(t)) | among r, s, t. | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | genus t over | |
| + | | r s | | species r, s. | |
| + | | o o | | | |
| + | | t | | | | partition t | |
| + | | o--o--o | | among r & s. | |
| + | | \ / | | | |
| + | | \ / | | whole pie t: | |
| + | | @ | ( t ,(r),(s)) | slices r, s. | |
| + | o-------------------o-------------------o-------------------o |
| + | </pre> |
| + | |} |
| + | |
| + | {| align="center" cellpadding="6" width="90%" |
| + | | align="center" | |
| + | <pre> |
| + | Table 13. The Existential Interpretation |
| + | o-------------------o-------------------o-------------------o |
| + | | Cactus Graph | Cactus Expression | Existential | |
| + | | | | Interpretation | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | @ | " " | true. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | o | | | |
| + | | | | | | |
| + | | @ | ( ) | untrue. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a | | | |
| + | | @ | a | a. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a | | | |
| + | | o | | | |
| + | | | | | | |
| + | | @ | (a) | not a. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b c | | | |
| + | | @ | a b c | a and b and c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b c | | | |
| + | | o o o | | | |
| + | | \|/ | | | |
| + | | o | | | |
| + | | | | | | |
| + | | @ | ((a)(b)(c)) | a or b or c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | | | a implies b. | |
| + | | a b | | | |
| + | | o---o | | if a then b. | |
| + | | | | | | |
| + | | @ | (a (b)) | no a sans b. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b | | | |
| + | | o---o | | a exclusive-or b. | |
| + | | \ / | | | |
| + | | @ | (a , b) | a not equal to b. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b | | | |
| + | | o---o | | | |
| + | | \ / | | | |
| + | | o | | a if & only if b. | |
| + | | | | | | |
| + | | @ | ((a , b)) | a equates with b. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b c | | | |
| + | | o--o--o | | | |
| + | | \ / | | | |
| + | | \ / | | just one false | |
| + | | @ | (a , b , c) | out of a, b, c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b c | | | |
| + | | o o o | | | |
| + | | | | | | | | |
| + | | o--o--o | | | |
| + | | \ / | | | |
| + | | \ / | | just one true | |
| + | | @ | ((a),(b),(c)) | among a, b, c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | | | genus a over | |
| + | | b c | | species b, c. | |
| + | | o o | | | |
| + | | a | | | | partition a | |
| + | | o--o--o | | among b & c. | |
| + | | \ / | | | |
| + | | \ / | | whole pie a: | |
| + | | @ | ( a ,(b),(c)) | slices b, c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | </pre> |
| + | |} |
| + | |
| + | {| align="center" cellpadding="6" width="90%" |
| + | | align="center" | |
| + | <pre> |
| + | Table 14. The Entitative Interpretation |
| + | o-------------------o-------------------o-------------------o |
| + | | Cactus Graph | Cactus Expression | Entitative | |
| + | | | | Interpretation | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | @ | " " | untrue. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | o | | | |
| + | | | | | | |
| + | | @ | ( ) | true. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a | | | |
| + | | @ | a | a. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a | | | |
| + | | o | | | |
| + | | | | | | |
| + | | @ | (a) | not a. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b c | | | |
| + | | @ | a b c | a or b or c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b c | | | |
| + | | o o o | | | |
| + | | \|/ | | | |
| + | | o | | | |
| + | | | | | | |
| + | | @ | ((a)(b)(c)) | a and b and c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | | | a implies b. | |
| + | | | | | |
| + | | o a | | if a then b. | |
| + | | | | | | |
| + | | @ b | (a) b | not a, or b. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b | | | |
| + | | o---o | | a if & only if b. | |
| + | | \ / | | | |
| + | | @ | (a , b) | a equates with b. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b | | | |
| + | | o---o | | | |
| + | | \ / | | | |
| + | | o | | a exclusive-or b. | |
| + | | | | | | |
| + | | @ | ((a , b)) | a not equal to b. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b c | | | |
| + | | o--o--o | | | |
| + | | \ / | | | |
| + | | \ / | | not just one true | |
| + | | @ | (a , b , c) | out of a, b, c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a b c | | | |
| + | | o--o--o | | | |
| + | | \ / | | | |
| + | | \ / | | | |
| + | | o | | | |
| + | | | | | just one true | |
| + | | @ | ((a , b , c)) | among a, b, c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | | | | | |
| + | | a | | | |
| + | | o | | genus a over | |
| + | | | b c | | species b, c. | |
| + | | o--o--o | | | |
| + | | \ / | | partition a | |
| + | | \ / | | among b & c. | |
| + | | o | | | |
| + | | | | | whole pie a: | |
| + | | @ | ( a ,(b),(c)) | slices b, c. | |
| + | | | | | |
| + | o-------------------o-------------------o-------------------o |
| + | </pre> |
| + | |} |
| + | |
| + | {| align="center" cellpadding="6" width="90%" |
| + | | align="center" | |
| + | <pre> |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | Graph | String | Entitative | Existential | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | @ | " " | untrue. | true. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | o | | | | |
| + | | | | | | | |
| + | | @ | ( ) | true. | untrue. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | r | | | | |
| + | | @ | r | r. | r. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | r | | | | |
| + | | o | | | | |
| + | | | | | | | |
| + | | @ | (r) | not r. | not r. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | r s t | | | | |
| + | | @ | r s t | r or s or t. | r and s and t. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | r s t | | | | |
| + | | o o o | | | | |
| + | | \|/ | | | | |
| + | | o | | | | |
| + | | | | | | | |
| + | | @ | ((r)(s)(t)) | r and s and t. | r or s or t. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | r implies s. | |
| + | | | | | | |
| + | | o r | | | if r then s. | |
| + | | | | | | | |
| + | | @ s | (r) s | not r, or s | no r sans s. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | r implies s. | |
| + | | r s | | | | |
| + | | o---o | | | if r then s. | |
| + | | | | | | | |
| + | | @ | (r (s)) | | no r sans s. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | r s | | | | |
| + | | o---o | | |r exclusive-or s.| |
| + | | \ / | | | | |
| + | | @ | (r , s) | |r not equal to s.| |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | r s | | | | |
| + | | o---o | | | | |
| + | | \ / | | | | |
| + | | o | | |r if & only if s.| |
| + | | | | | | | |
| + | | @ | ((r , s)) | |r equates with s.| |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | r s t | | | | |
| + | | o--o--o | | | | |
| + | | \ / | | | | |
| + | | \ / | | | just one false | |
| + | | @ | (r , s , t) | | out of r, s, t. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | | |
| + | | r s t | | | | |
| + | | o o o | | | | |
| + | | | | | | | | | |
| + | | o--o--o | | | | |
| + | | \ / | | | | |
| + | | \ / | | | just one true | |
| + | | @ | ((r),(s),(t)) | | among r, s, t. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | | | | | genus t over | |
| + | | r s | | | species r, s. | |
| + | | o o | | | | |
| + | | t | | | | | partition t | |
| + | | o--o--o | | | among r & s. | |
| + | | \ / | | | | |
| + | | \ / | | | whole pie t: | |
| + | | @ | ( t ,(r),(s)) | | slices r, s. | |
| + | o-----------------o-----------------o-----------------o-----------------o |
| + | </pre> |
| + | |} |
| + | |
| + | ===Zeroth Order Logic=== |
| + | |
| + | <pre> |
| + | Here is a scaled-down version of one of my very first applications, |
| + | having to do with the demographic variables in a survey data base. |
| + | |
| + | This Example illustrates the use of 2-variate logical forms |
| + | for expressing and reasoning about the logical constraints |
| + | that are involved in the following types of situations: |
| + | |
| + | 1. Distinction: A =/= B |
| + | Also known as: logical inequality, exclusive disjunction |
| + | Represented as: ( A , B ) |
| + | Graphed as: |
| + | | |
| + | | A B |
| + | | o---o |
| + | | \ / |
| + | | @ |
| + | |
| + | 2. Equality: A = B |
| + | Also known as: logical equivalence, if and only if, A <=> B |
| + | Represented as: (( A , B )) |
| + | Graphed as: |
| + | | |
| + | | A B |
| + | | o---o |
| + | | \ / |
| + | | o |
| + | | | |
| + | | @ |
| + | |
| + | 3. Implication: A => B |
| + | Also known as: entailment, if-then |
| + | Represented as: ( A ( B )) |
| + | Graphed as: |
| + | | |
| + | | A B |
| + | | o---o |
| + | | | |
| + | | @ |
| + | |
| + | Example of a proposition expressing a "zeroth order theory" (ZOT): |
| + | |
| + | Consider the following text, written in what I am calling "Ref Log", |
| + | also known as the "Cactus Language" synpropositional logic: |
| + | |
| + | | ( male , female ) |
| + | | (( boy , male child )) |
| + | | (( girl , female child )) |
| + | | ( child ( human )) |
| + | |
| + | Graphed as: |
| + | |
| + | | boy male girl female |
| + | | o---o child o---o child |
| + | | male female \ / \ / child human |
| + | | o---o o o o---o |
| + | | \ / | | | |
| + | | @ @ @ @| |
| + | |
| + | Nota Bene. Due to graphic constraints -- no, the other |
| + | kind of graphic constraints -- of the immediate medium, |
| + | I am forced to string out the logical conjuncts of the |
| + | actual cactus graph for this situation, one that might |
| + | sufficiently be reasoned out from the exhibit supra by |
| + | fusing together the four roots of the severed cactus. |
| + | |
| + | Either of these expressions, text or graph, is equivalent to |
| + | what would otherwise be written in a more ordinary syntax as: |
| + | |
| + | | male =/= female |
| + | | boy <=> male child |
| + | | girl <=> female child |
| + | | child => human |
| + | |
| + | This is a actually a single proposition, a conjunction of four lines: |
| + | one distinction, two equations, and one implication. Together these |
| + | amount to a set of definitions conjointly constraining the logical |
| + | compatibility of the six feature names that appear. They may be |
| + | thought of as sculpting out a space of models that is some subset |
| + | of the 2^6 = 64 possible interpretations, and thereby shaping some |
| + | universe of discourse. |
| + | |
| + | Once this backdrop is defined, it is possible to "query" this universe, |
| + | simply by conjoining additional propositions in further constraint of |
| + | the underlying set of models. This has many uses, as we shall see. |
| + | |
| + | We are considering an Example of a propositional expression |
| + | that is formed on the following "alphabet" or "lexicon" of |
| + | six "logical features" or "boolean variables": |
| + | |
| + | $A$ = {"boy", "child", "female", "girl", "human", "male"}. |
| + | |
| + | The expression is this: |
| + | |
| + | | ( male , female ) |
| + | | (( boy , male child )) |
| + | | (( girl , female child )) |
| + | | ( child ( human )) |
| + | |
| + | Putting it very roughly -- and putting off a better description |
| + | of it till later -- we may think of this expression as notation |
| + | for a boolean function f : %B%^6 -> %B%. This is what we might |
| + | call the "abstract type" of the function, but we will also find |
| + | it convenient on many occasions to represent the points of this |
| + | particular copy of the space %B%^6 in terms of the positive and |
| + | negative versions of the features from $A$ that serve to encase |
| + | them as logical "cells", as they are called in the venn diagram |
| + | picture of the corresponding universe of discourse X = [$A$]. |
| + | |
| + | Just for concreteness, this form of representation begins and ends: |
| + | |
| + | <0,0,0,0,0,0> = (boy)(child)(female)(girl)(human)(male), |
| + | <0,0,0,0,0,1> = (boy)(child)(female)(girl)(human) male , |
| + | <0,0,0,0,1,0> = (boy)(child)(female)(girl) human (male), |
| + | <0,0,0,0,1,1> = (boy)(child)(female)(girl) human male , |
| + | ... |
| + | <1,1,1,1,0,0> = boy child female girl (human)(male), |
| + | <1,1,1,1,0,1> = boy child female girl (human) male , |
| + | <1,1,1,1,1,0> = boy child female girl human (male), |
| + | <1,1,1,1,1,1> = boy child female girl human male . |
| + | |
| + | I continue with the previous Example, that I bring forward and sum up here: |
| + | |
| + | | boy male girl female |
| + | | o---o child o---o child |
| + | | male female \ / \ / child human |
| + | | o---o o o o--o |
| + | | \ / | | | |
| + | | @ @ @ @ |
| + | | |
| + | | (male , female)((boy , male child))((girl , female child))(child (human)) |
| + | |
| + | For my master's piece in Quantitative Psychology (Michigan State, 1989), |
| + | I wrote a program, "Theme One" (TO) by name, that among its other duties |
| + | operates to process the expressions of the cactus language in many of the |
| + | most pressing ways that we need in order to be able to use it effectively |
| + | as a propositional calculus. The operational component of TO where one |
| + | does the work of this logical modeling is called "Study", and the core |
| + | of the logical calculator deep in the heart of this Study section is |
| + | a suite of computational functions that evolve a particular species |
| + | of "normal form", analogous to a "disjunctive normal form" (DNF), |
| + | from whatever expression they are prebendered as their input. |
| + | |
| + | This "canonical", "normal", or "stable" form of logical expression -- |
| + | I'll refine the distinctions among these subforms all in good time -- |
| + | permits succinct depiction as an "arboreal boolean expansion" (ABE). |
| + | |
| + | Once again, the graphic limitations of this space prevail against |
| + | any disposition that I might have to lay out a really substantial |
| + | case before you, of the brand that might have a chance to impress |
| + | you with the aptitude of this ilk of ABE in rooting out the truth |
| + | of many a complexly obscurely subtly adamant whetstone of our wit. |
| + | |
| + | So let me just illustrate the way of it with one conjunct of our Example. |
| + | What follows will be a sequence of expressions, each one after the first |
| + | being logically equal to the one that precedes it: |
| + | |
| + | Step 1 |
| + | |
| + | | g fc |
| + | | o---o |
| + | | \ / |
| + | | o |
| + | | | |
| + | | @ |
| + | |
| + | Step 2 |
| + | |
| + | | o |
| + | | fc | fc |
| + | | o---o o---o |
| + | | \ / \ / |
| + | | o o |
| + | | | | |
| + | | g o-------------o--o g |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | @ |
| + | |
| + | Step 3 |
| + | |
| + | | f c |
| + | | o |
| + | | | f c |
| + | | o o |
| + | | | | |
| + | | g o-------------o--o g |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | @ |
| + | |
| + | Step 4 |
| + | |
| + | | o |
| + | | | |
| + | | c o o c o |
| + | | | | | |
| + | | o o c o o c |
| + | | | | | | |
| + | | f o---o--o f f o---o--o f |
| + | | \ / \ / |
| + | | g o-------------o--o g |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | @ |
| + | |
| + | Step 5 |
| + | |
| + | | o c o |
| + | | c | | |
| + | | f o---o--o f f o---o--o f |
| + | | \ / \ / |
| + | | g o-------------o--o g |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | @ |
| + | |
| + | Step 6 |
| + | |
| + | | o |
| + | | | |
| + | | o o o |
| + | | | | | |
| + | | c o---o--o c o c o---o--o c |
| + | | \ / | \ / |
| + | | f o-------------o--o f f o-------------o--o f |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | g o---------------------------o--o g |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | @ |
| + | |
| + | Step 7 |
| + | |
| + | | o o |
| + | | | | |
| + | | c o---o--o c o c o---o--o c |
| + | | \ / | \ / |
| + | | f o-------------o--o f f o-------------o--o f |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | \ / \ / |
| + | | g o---------------------------o--o g |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | \ / |
| + | | @ |
| + | |
| + | This last expression is the ABE of the input expression. |
| + | It can be transcribed into ordinary logical language as: |
| + | |
| + | | either girl and |
| + | | either female and |
| + | | either child and true |
| + | | or not child and false |
| + | | or not female and false |
| + | | or not girl and |
| + | | either female and |
| + | | either child and false |
| + | | or not child and true |
| + | | or not female and true |
| + | |
| + | The expression "((girl , female child))" is sufficiently evaluated |
| + | by considering its logical values on the coordinate tuples of %B%^3, |
| + | or its indications on the cells of the associated venn diagram that |
| + | depicts the universe of discourse, namely, on these eight arguments: |
| + | |
| + | <1, 1, 1> = girl female child , |
| + | <1, 1, 0> = girl female (child), |
| + | <1, 0, 1> = girl (female) child , |
| + | <1, 0, 0> = girl (female)(child), |
| + | <0, 1, 1> = (girl) female child , |
| + | <0, 1, 0> = (girl) female (child), |
| + | <0, 0, 1> = (girl)(female) child , |
| + | <0, 0, 0> = (girl)(female)(child). |
| + | |
| + | The ABE output expression tells us the logical values of |
| + | the input expression on each of these arguments, doing so |
| + | by attaching the values to the leaves of a tree, and acting |
| + | as an "efficient" or "lazy" evaluator in the sense that the |
| + | process that generates the tree follows each path only up to |
| + | the point in the tree where it can determine the values on the |
| + | entire subtree beyond that point. Thus, the ABE tree tells us: |
| + | |
| + | girl female child -> 1 |
| + | girl female (child) -> 0 |
| + | girl (female) -> 0 |
| + | (girl) female child -> 0 |
| + | (girl) female (child) -> 1 |
| + | (girl)(female) -> 1 |
| + | |
| + | Picking out the interpretations that yield the truth of the expression, |
| + | and expanding the corresponding partial argument tuples, we arrive at |
| + | the following interpretations that satisfy the input expression: |
| + | |
| + | girl female child -> 1 |
| + | (girl) female (child) -> 1 |
| + | (girl)(female) child -> 1 |
| + | (girl)(female)(child) -> 1 |
| + | |
| + | In sum, if it's a female and a child, then it's a girl, |
| + | and if it's either not a female or not a child or both, |
| + | then it's not a girl. |
| + | |
| + | Brief Automata |
| + | |
| + | By way of providing a simple illustration of Cook's Theorem, |
| + | that "Propositional Satisfiability is NP-Complete", here is |
| + | an exposition of one way to translate Turing Machine set-ups |
| + | into propositional expressions, employing the Ref Log Syntax |
| + | for Prop Calc that I described in a couple of earlier notes: |
| + | |
| + | Notation: |
| + | |
| + | Stilt(k) = Space and Time Limited Turing Machine, |
| + | with k units of space and k units of time. |
| + | |
| + | Stunt(k) = Space and Time Limited Turing Machine, |
| + | for computing the parity of a bit string, |
| + | with Number of Tape cells of input equal to k. |
| + | |
| + | I will follow the pattern of the discussion in the book of |
| + | Herbert Wilf, 'Algorithms & Complexity' (1986), pages 188-201, |
| + | but translate into Ref Log, which is more efficient with respect |
| + | to the number of propositional clauses that are required. |
| + | |
| + | Parity Machine |
| + | |
| + | | 1/1/+1 |
| + | | -------> |
| + | | /\ / \ /\ |
| + | | 0/0/+1 ^ 0 1 ^ 0/0/+1 |
| + | | \/|\ /|\/ |
| + | | | <------- | |
| + | | #/#/-1 | 1/1/+1 | #/#/-1 |
| + | | | | |
| + | | v v |
| + | | # * |
| + | |
| + | o-------o--------o-------------o---------o------------o |
| + | | State | Symbol | Next Symbol | Ratchet | Next State | |
| + | | Q | S | S' | dR | Q' | |
| + | o-------o--------o-------------o---------o------------o |
| + | | 0 | 0 | 0 | +1 | 0 | |
| + | | 0 | 1 | 1 | +1 | 1 | |
| + | | 0 | # | # | -1 | # | |
| + | | 1 | 0 | 0 | +1 | 1 | |
| + | | 1 | 1 | 1 | +1 | 0 | |
| + | | 1 | # | # | -1 | * | |
| + | o-------o--------o-------------o---------o------------o |
| + | |
| + | The TM has a "finite automaton" (FA) as its component. |
| + | Let us refer to this particular FA by the name of "M". |
| + | |
| + | The "tape-head" (that is, the "read-unit") will be called "H". |
| + | The "registers" are also called "tape-cells" or "tape-squares". |
| + | |
| + | In order to consider how the finitely "stilted" rendition of this TM |
| + | can be translated into the form of a purely propositional description, |
| + | one now fixes k and limits the discussion to talking about a Stilt(k), |
| + | which is really not a true TM anymore but a finite automaton in disguise. |
| + | |
| + | In this example, for the sake of a minimal illustration, we choose k = 2, |
| + | and discuss Stunt(2). Since the zeroth tape cell and the last tape cell |
| + | are occupied with bof and eof marks "#", this amounts to only one digit |
| + | of significant computation. |
| + | |
| + | To translate Stunt(2) into propositional form we use |
| + | the following collection of propositional variables: |
| + | |
| + | For the "Present State Function" QF : P -> Q, |
| + | |
| + | {p0_q#, p0_q*, p0_q0, p0_q1, |
| + | p1_q#, p1_q*, p1_q0, p1_q1, |
| + | p2_q#, p2_q*, p2_q0, p2_q1, |
| + | p3_q#, p3_q*, p3_q0, p3_q1} |
| + | |
| + | The propositional expression of the form "pi_qj" says: |
| + | |
| + | | At the point-in-time p_i, |
| + | | the finite machine M is in the state q_j. |
| + | |
| + | For the "Present Register Function" RF : P -> R, |
| + | |
| + | {p0_r0, p0_r1, p0_r2, p0_r3, |
| + | p1_r0, p1_r1, p1_r2, p1_r3, |
| + | p2_r0, p2_r1, p2_r2, p2_r3, |
| + | p3_r0, p3_r1, p3_r2, p3_r3} |
| + | |
| + | The propositional expression of the form "pi_rj" says: |
| + | |
| + | | At the point-in-time p_i, |
| + | | the tape-head H is on the tape-cell r_j. |
| + | |
| + | For the "Present Symbol Function" SF : P -> (R -> S), |
| + | |
| + | {p0_r0_s#, p0_r0_s*, p0_r0_s0, p0_r0_s1, |
| + | p0_r1_s#, p0_r1_s*, p0_r1_s0, p0_r1_s1, |
| + | p0_r2_s#, p0_r2_s*, p0_r2_s0, p0_r2_s1, |
| + | p0_r3_s#, p0_r3_s*, p0_r3_s0, p0_r3_s1, |
| + | p1_r0_s#, p1_r0_s*, p1_r0_s0, p1_r0_s1, |
| + | p1_r1_s#, p1_r1_s*, p1_r1_s0, p1_r1_s1, |
| + | p1_r2_s#, p1_r2_s*, p1_r2_s0, p1_r2_s1, |
| + | p1_r3_s#, p1_r3_s*, p1_r3_s0, p1_r3_s1, |
| + | p2_r0_s#, p2_r0_s*, p2_r0_s0, p2_r0_s1, |
| + | p2_r1_s#, p2_r1_s*, p2_r1_s0, p2_r1_s1, |
| + | p2_r2_s#, p2_r2_s*, p2_r2_s0, p2_r2_s1, |
| + | p2_r3_s#, p2_r3_s*, p2_r3_s0, p2_r3_s1, |
| + | p3_r0_s#, p3_r0_s*, p3_r0_s0, p3_r0_s1, |
| + | p3_r1_s#, p3_r1_s*, p3_r1_s0, p3_r1_s1, |
| + | p3_r2_s#, p3_r2_s*, p3_r2_s0, p3_r2_s1, |
| + | p3_r3_s#, p3_r3_s*, p3_r3_s0, p3_r3_s1} |
| + | |
| + | The propositional expression of the form "pi_rj_sk" says: |
| + | |
| + | | At the point-in-time p_i, |
| + | | the tape-cell r_j bears the mark s_k. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~INPUTS~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Here are the Initial Conditions |
| + | for the two possible inputs to the |
| + | Ref Log redaction of this Parity TM: |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~INPUT~0~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Initial Conditions: |
| + | |
| + | p0_q0 |
| + | |
| + | p0_r1 |
| + | |
| + | p0_r0_s# |
| + | p0_r1_s0 |
| + | p0_r2_s# |
| + | |
| + | The Initial Conditions are given by a logical conjunction |
| + | that is composed of 5 basic expressions, altogether stating: |
| + | |
| + | | At the point-in-time p_0, M is in the state q_0, and |
| + | | At the point-in-time p_0, H is on the cell r_1, and |
| + | | At the point-in-time p_0, cell r_0 bears the mark "#", and |
| + | | At the point-in-time p_0, cell r_1 bears the mark "0", and |
| + | | At the point-in-time p_0, cell r_2 bears the mark "#". |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~INPUT~1~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Initial Conditions: |
| + | |
| + | p0_q0 |
| + | |
| + | p0_r1 |
| + | |
| + | p0_r0_s# |
| + | p0_r1_s1 |
| + | p0_r2_s# |
| + | |
| + | The Initial Conditions are given by a logical conjunction |
| + | that is composed of 5 basic expressions, altogether stating: |
| + | |
| + | | At the point-in-time p_0, M is in the state q_0, and |
| + | | At the point-in-time p_0, H is on the cell r_1, and |
| + | | At the point-in-time p_0, cell r_0 bears the mark "#", and |
| + | | At the point-in-time p_0, cell r_1 bears the mark "1", and |
| + | | At the point-in-time p_0, cell r_2 bears the mark "#". |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~PROGRAM~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | And here, yet again, just to store it nearby, |
| + | is the logical rendition of the TM's program: |
| + | |
| + | Mediate Conditions: |
| + | |
| + | ( p0_q# ( p1_q# )) |
| + | ( p0_q* ( p1_q* )) |
| + | |
| + | ( p1_q# ( p2_q# )) |
| + | ( p1_q* ( p2_q* )) |
| + | |
| + | Terminal Conditions: |
| + | |
| + | (( p2_q# )( p2_q* )) |
| + | |
| + | State Partition: |
| + | |
| + | (( p0_q0 ),( p0_q1 ),( p0_q# ),( p0_q* )) |
| + | (( p1_q0 ),( p1_q1 ),( p1_q# ),( p1_q* )) |
| + | (( p2_q0 ),( p2_q1 ),( p2_q# ),( p2_q* )) |
| + | |
| + | Register Partition: |
| + | |
| + | (( p0_r0 ),( p0_r1 ),( p0_r2 )) |
| + | (( p1_r0 ),( p1_r1 ),( p1_r2 )) |
| + | (( p2_r0 ),( p2_r1 ),( p2_r2 )) |
| + | |
| + | Symbol Partition: |
| + | |
| + | (( p0_r0_s0 ),( p0_r0_s1 ),( p0_r0_s# )) |
| + | (( p0_r1_s0 ),( p0_r1_s1 ),( p0_r1_s# )) |
| + | (( p0_r2_s0 ),( p0_r2_s1 ),( p0_r2_s# )) |
| + | |
| + | (( p1_r0_s0 ),( p1_r0_s1 ),( p1_r0_s# )) |
| + | (( p1_r1_s0 ),( p1_r1_s1 ),( p1_r1_s# )) |
| + | (( p1_r2_s0 ),( p1_r2_s1 ),( p1_r2_s# )) |
| + | |
| + | (( p2_r0_s0 ),( p2_r0_s1 ),( p2_r0_s# )) |
| + | (( p2_r1_s0 ),( p2_r1_s1 ),( p2_r1_s# )) |
| + | (( p2_r2_s0 ),( p2_r2_s1 ),( p2_r2_s# )) |
| + | |
| + | Interaction Conditions: |
| + | |
| + | (( p0_r0 ) p0_r0_s0 ( p1_r0_s0 )) |
| + | (( p0_r0 ) p0_r0_s1 ( p1_r0_s1 )) |
| + | (( p0_r0 ) p0_r0_s# ( p1_r0_s# )) |
| + | |
| + | (( p0_r1 ) p0_r1_s0 ( p1_r1_s0 )) |
| + | (( p0_r1 ) p0_r1_s1 ( p1_r1_s1 )) |
| + | (( p0_r1 ) p0_r1_s# ( p1_r1_s# )) |
| + | |
| + | (( p0_r2 ) p0_r2_s0 ( p1_r2_s0 )) |
| + | (( p0_r2 ) p0_r2_s1 ( p1_r2_s1 )) |
| + | (( p0_r2 ) p0_r2_s# ( p1_r2_s# )) |
| + | |
| + | (( p1_r0 ) p1_r0_s0 ( p2_r0_s0 )) |
| + | (( p1_r0 ) p1_r0_s1 ( p2_r0_s1 )) |
| + | (( p1_r0 ) p1_r0_s# ( p2_r0_s# )) |
| + | |
| + | (( p1_r1 ) p1_r1_s0 ( p2_r1_s0 )) |
| + | (( p1_r1 ) p1_r1_s1 ( p2_r1_s1 )) |
| + | (( p1_r1 ) p1_r1_s# ( p2_r1_s# )) |
| + | |
| + | (( p1_r2 ) p1_r2_s0 ( p2_r2_s0 )) |
| + | (( p1_r2 ) p1_r2_s1 ( p2_r2_s1 )) |
| + | (( p1_r2 ) p1_r2_s# ( p2_r2_s# )) |
| + | |
| + | Transition Relations: |
| + | |
| + | ( p0_q0 p0_r1 p0_r1_s0 ( p1_q0 p1_r2 p1_r1_s0 )) |
| + | ( p0_q0 p0_r1 p0_r1_s1 ( p1_q1 p1_r2 p1_r1_s1 )) |
| + | ( p0_q0 p0_r1 p0_r1_s# ( p1_q# p1_r0 p1_r1_s# )) |
| + | ( p0_q0 p0_r2 p0_r2_s# ( p1_q# p1_r1 p1_r2_s# )) |
| + | |
| + | ( p0_q1 p0_r1 p0_r1_s0 ( p1_q1 p1_r2 p1_r1_s0 )) |
| + | ( p0_q1 p0_r1 p0_r1_s1 ( p1_q0 p1_r2 p1_r1_s1 )) |
| + | ( p0_q1 p0_r1 p0_r1_s# ( p1_q* p1_r0 p1_r1_s# )) |
| + | ( p0_q1 p0_r2 p0_r2_s# ( p1_q* p1_r1 p1_r2_s# )) |
| + | |
| + | ( p1_q0 p1_r1 p1_r1_s0 ( p2_q0 p2_r2 p2_r1_s0 )) |
| + | ( p1_q0 p1_r1 p1_r1_s1 ( p2_q1 p2_r2 p2_r1_s1 )) |
| + | ( p1_q0 p1_r1 p1_r1_s# ( p2_q# p2_r0 p2_r1_s# )) |
| + | ( p1_q0 p1_r2 p1_r2_s# ( p2_q# p2_r1 p2_r2_s# )) |
| + | |
| + | ( p1_q1 p1_r1 p1_r1_s0 ( p2_q1 p2_r2 p2_r1_s0 )) |
| + | ( p1_q1 p1_r1 p1_r1_s1 ( p2_q0 p2_r2 p2_r1_s1 )) |
| + | ( p1_q1 p1_r1 p1_r1_s# ( p2_q* p2_r0 p2_r1_s# )) |
| + | ( p1_q1 p1_r2 p1_r2_s# ( p2_q* p2_r1 p2_r2_s# )) |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~INTERPRETATION~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Interpretation of the Propositional Program: |
| + | |
| + | Mediate Conditions: |
| + | |
| + | ( p0_q# ( p1_q# )) |
| + | ( p0_q* ( p1_q* )) |
| + | |
| + | ( p1_q# ( p2_q# )) |
| + | ( p1_q* ( p2_q* )) |
| + | |
| + | In Ref Log, an expression of the form "( X ( Y ))" |
| + | expresses an implication or an if-then proposition: |
| + | "Not X without Y", "If X then Y", "X => Y", etc. |
| + | |
| + | A text string expression of the form "( X ( Y ))" |
| + | parses to a graphical data-structure of the form: |
| + | |
| + | X Y |
| + | o---o |
| + | | |
| + | @ |
| + | |
| + | All together, these Mediate Conditions state: |
| + | |
| + | | If at p_0 M is in state q_#, then at p_1 M is in state q_#, and |
| + | | If at p_0 M is in state q_*, then at p_1 M is in state q_*, and |
| + | | If at p_1 M is in state q_#, then at p_2 M is in state q_#, and |
| + | | If at p_1 M is in state q_*, then at p_2 M is in state q_*. |
| + | |
| + | Terminal Conditions: |
| + | |
| + | (( p2_q# )( p2_q* )) |
| + | |
| + | In Ref Log, an expression of the form "(( X )( Y ))" |
| + | expresses a disjunction "X or Y" and it parses into: |
| + | |
| + | X Y |
| + | o o |
| + | \ / |
| + | o |
| + | | |
| + | @ |
| + | |
| + | In effect, the Terminal Conditions state: |
| + | |
| + | | At p_2, M is in state q_#, or |
| + | | At p_2, M is in state q_*. |
| + | |
| + | State Partition: |
| + | |
| + | (( p0_q0 ),( p0_q1 ),( p0_q# ),( p0_q* )) |
| + | (( p1_q0 ),( p1_q1 ),( p1_q# ),( p1_q* )) |
| + | (( p2_q0 ),( p2_q1 ),( p2_q# ),( p2_q* )) |
| + | |
| + | In Ref Log, an expression of the form "(( e_1 ),( e_2 ),( ... ),( e_k ))" |
| + | expresses the fact that "exactly one of the e_j is true, for j = 1 to k". |
| + | Expressions of this form are called "universal partition" expressions, and |
| + | they parse into a type of graph called a "painted and rooted cactus" (PARC): |
| + | |
| + | e_1 e_2 ... e_k |
| + | o o o |
| + | | | | |
| + | o-----o--- ... ---o |
| + | \ / |
| + | \ / |
| + | \ / |
| + | \ / |
| + | \ / |
| + | \ / |
| + | \ / |
| + | \ / |
| + | @ |
| + | |
| + | The State Partition expresses the conditions that: |
| + | |
| + | | At each of the points-in-time p_i, for i = 0 to 2, |
| + | | M can be in exactly one state q_j, for j in the set {0, 1, #, *}. |
| + | |
| + | Register Partition: |
| + | |
| + | (( p0_r0 ),( p0_r1 ),( p0_r2 )) |
| + | (( p1_r0 ),( p1_r1 ),( p1_r2 )) |
| + | (( p2_r0 ),( p2_r1 ),( p2_r2 )) |
| + | |
| + | The Register Partition expresses the conditions that: |
| + | |
| + | | At each of the points-in-time p_i, for i = 0 to 2, |
| + | | H can be on exactly one cell r_j, for j = 0 to 2. |
| + | |
| + | Symbol Partition: |
| + | |
| + | (( p0_r0_s0 ),( p0_r0_s1 ),( p0_r0_s# )) |
| + | (( p0_r1_s0 ),( p0_r1_s1 ),( p0_r1_s# )) |
| + | (( p0_r2_s0 ),( p0_r2_s1 ),( p0_r2_s# )) |
| + | |
| + | (( p1_r0_s0 ),( p1_r0_s1 ),( p1_r0_s# )) |
| + | (( p1_r1_s0 ),( p1_r1_s1 ),( p1_r1_s# )) |
| + | (( p1_r2_s0 ),( p1_r2_s1 ),( p1_r2_s# )) |
| + | |
| + | (( p2_r0_s0 ),( p2_r0_s1 ),( p2_r0_s# )) |
| + | (( p2_r1_s0 ),( p2_r1_s1 ),( p2_r1_s# )) |
| + | (( p2_r2_s0 ),( p2_r2_s1 ),( p2_r2_s# )) |
| + | |
| + | The Symbol Partition expresses the conditions that: |
| + | |
| + | | At each of the points-in-time p_i, for i in {0, 1, 2}, |
| + | | in each of the tape-registers r_j, for j in {0, 1, 2}, |
| + | | there can be exactly one sign s_k, for k in {0, 1, #}. |
| + | |
| + | Interaction Conditions: |
| + | |
| + | (( p0_r0 ) p0_r0_s0 ( p1_r0_s0 )) |
| + | (( p0_r0 ) p0_r0_s1 ( p1_r0_s1 )) |
| + | (( p0_r0 ) p0_r0_s# ( p1_r0_s# )) |
| + | |
| + | (( p0_r1 ) p0_r1_s0 ( p1_r1_s0 )) |
| + | (( p0_r1 ) p0_r1_s1 ( p1_r1_s1 )) |
| + | (( p0_r1 ) p0_r1_s# ( p1_r1_s# )) |
| + | |
| + | (( p0_r2 ) p0_r2_s0 ( p1_r2_s0 )) |
| + | (( p0_r2 ) p0_r2_s1 ( p1_r2_s1 )) |
| + | (( p0_r2 ) p0_r2_s# ( p1_r2_s# )) |
| + | |
| + | (( p1_r0 ) p1_r0_s0 ( p2_r0_s0 )) |
| + | (( p1_r0 ) p1_r0_s1 ( p2_r0_s1 )) |
| + | (( p1_r0 ) p1_r0_s# ( p2_r0_s# )) |
| + | |
| + | (( p1_r1 ) p1_r1_s0 ( p2_r1_s0 )) |
| + | (( p1_r1 ) p1_r1_s1 ( p2_r1_s1 )) |
| + | (( p1_r1 ) p1_r1_s# ( p2_r1_s# )) |
| + | |
| + | (( p1_r2 ) p1_r2_s0 ( p2_r2_s0 )) |
| + | (( p1_r2 ) p1_r2_s1 ( p2_r2_s1 )) |
| + | (( p1_r2 ) p1_r2_s# ( p2_r2_s# )) |
| + | |
| + | In briefest terms, the Interaction Conditions merely express |
| + | the circumstance that the sign in a tape-cell cannot change |
| + | between two points-in-time unless the tape-head is over the |
| + | cell in question at the initial one of those points-in-time. |
| + | All that we have to do is to see how they manage to say this. |
| + | |
| + | In Ref Log, an expression of the following form: |
| + | |
| + | "(( p<i>_r<j> ) p<i>_r<j>_s<k> ( p<i+1>_r<j>_s<k> ))", |
| + | |
| + | and which parses as the graph: |
| + | |
| + | p<i>_r<j> o o p<i+1>_r<j>_s<k> |
| + | \ / |
| + | p<i>_r<j>_s<k> o |
| + | | |
| + | @ |
| + | |
| + | can be read in the form of the following implication: |
| + | |
| + | | If |
| + | | at the point-in-time p<i>, the tape-cell r<j> bears the mark s<k>, |
| + | | but it is not the case that |
| + | | at the point-in-time p<i>, the tape-head is on the tape-cell r<j>. |
| + | | then |
| + | | at the point-in-time p<i+1>, the tape-cell r<j> bears the mark s<k>. |
| + | |
| + | Folks among us of a certain age and a peculiar manner of acculturation will |
| + | recognize these as the "Frame Conditions" for the change of state of the TM. |
| + | |
| + | Transition Relations: |
| + | |
| + | ( p0_q0 p0_r1 p0_r1_s0 ( p1_q0 p1_r2 p1_r1_s0 )) |
| + | ( p0_q0 p0_r1 p0_r1_s1 ( p1_q1 p1_r2 p1_r1_s1 )) |
| + | ( p0_q0 p0_r1 p0_r1_s# ( p1_q# p1_r0 p1_r1_s# )) |
| + | ( p0_q0 p0_r2 p0_r2_s# ( p1_q# p1_r1 p1_r2_s# )) |
| + | |
| + | ( p0_q1 p0_r1 p0_r1_s0 ( p1_q1 p1_r2 p1_r1_s0 )) |
| + | ( p0_q1 p0_r1 p0_r1_s1 ( p1_q0 p1_r2 p1_r1_s1 )) |
| + | ( p0_q1 p0_r1 p0_r1_s# ( p1_q* p1_r0 p1_r1_s# )) |
| + | ( p0_q1 p0_r2 p0_r2_s# ( p1_q* p1_r1 p1_r2_s# )) |
| + | |
| + | ( p1_q0 p1_r1 p1_r1_s0 ( p2_q0 p2_r2 p2_r1_s0 )) |
| + | ( p1_q0 p1_r1 p1_r1_s1 ( p2_q1 p2_r2 p2_r1_s1 )) |
| + | ( p1_q0 p1_r1 p1_r1_s# ( p2_q# p2_r0 p2_r1_s# )) |
| + | ( p1_q0 p1_r2 p1_r2_s# ( p2_q# p2_r1 p2_r2_s# )) |
| + | |
| + | ( p1_q1 p1_r1 p1_r1_s0 ( p2_q1 p2_r2 p2_r1_s0 )) |
| + | ( p1_q1 p1_r1 p1_r1_s1 ( p2_q0 p2_r2 p2_r1_s1 )) |
| + | ( p1_q1 p1_r1 p1_r1_s# ( p2_q* p2_r0 p2_r1_s# )) |
| + | ( p1_q1 p1_r2 p1_r2_s# ( p2_q* p2_r1 p2_r2_s# )) |
| + | |
| + | The Transition Conditions merely serve to express, |
| + | by means of 16 complex implication expressions, |
| + | the data of the TM table that was given above. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~OUTPUTS~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | And here are the outputs of the computation, |
| + | as emulated by its propositional rendition, |
| + | and as actually generated within that form |
| + | of transmogrification by the program that |
| + | I wrote for finding all of the satisfying |
| + | interpretations (truth-value assignments) |
| + | of propositional expressions in Ref Log: |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~OUTPUT~0~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Output Conditions: |
| + | |
| + | p0_q0 |
| + | p0_r1 |
| + | p0_r0_s# |
| + | p0_r1_s0 |
| + | p0_r2_s# |
| + | p1_q0 |
| + | p1_r2 |
| + | p1_r2_s# |
| + | p1_r0_s# |
| + | p1_r1_s0 |
| + | p2_q# |
| + | p2_r1 |
| + | p2_r0_s# |
| + | p2_r1_s0 |
| + | p2_r2_s# |
| + | |
| + | The Output Conditions amount to the sole satisfying interpretation, |
| + | that is, a "sequence of truth-value assignments" (SOTVA) that make |
| + | the entire proposition come out true, and they state the following: |
| + | |
| + | | At the point-in-time p_0, M is in the state q_0, and |
| + | | At the point-in-time p_0, H is on the cell r_1, and |
| + | | At the point-in-time p_0, cell r_0 bears the mark "#", and |
| + | | At the point-in-time p_0, cell r_1 bears the mark "0", and |
| + | | At the point-in-time p_0, cell r_2 bears the mark "#", and |
| + | | |
| + | | At the point-in-time p_1, M is in the state q_0, and |
| + | | At the point-in-time p_1, H is on the cell r_2, and |
| + | | At the point-in-time p_1, cell r_0 bears the mark "#", and |
| + | | At the point-in-time p_1, cell r_1 bears the mark "0", and |
| + | | At the point-in-time p_1, cell r_2 bears the mark "#", and |
| + | | |
| + | | At the point-in-time p_2, M is in the state q_#, and |
| + | | At the point-in-time p_2, H is on the cell r_1, and |
| + | | At the point-in-time p_2, cell r_0 bears the mark "#", and |
| + | | At the point-in-time p_2, cell r_1 bears the mark "0", and |
| + | | At the point-in-time p_2, cell r_2 bears the mark "#". |
| + | |
| + | In brief, the output for our sake being the symbol that rests |
| + | under the tape-head H when the machine M gets to a rest state, |
| + | we are now amazed by the remarkable result that Parity(0) = 0. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~OUTPUT~1~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Output Conditions: |
| + | |
| + | p0_q0 |
| + | p0_r1 |
| + | p0_r0_s# |
| + | p0_r1_s1 |
| + | p0_r2_s# |
| + | p1_q1 |
| + | p1_r2 |
| + | p1_r2_s# |
| + | p1_r0_s# |
| + | p1_r1_s1 |
| + | p2_q* |
| + | p2_r1 |
| + | p2_r0_s# |
| + | p2_r1_s1 |
| + | p2_r2_s# |
| + | |
| + | The Output Conditions amount to the sole satisfying interpretation, |
| + | that is, a "sequence of truth-value assignments" (SOTVA) that make |
| + | the entire proposition come out true, and they state the following: |
| + | |
| + | | At the point-in-time p_0, M is in the state q_0, and |
| + | | At the point-in-time p_0, H is on the cell r_1, and |
| + | | At the point-in-time p_0, cell r_0 bears the mark "#", and |
| + | | At the point-in-time p_0, cell r_1 bears the mark "1", and |
| + | | At the point-in-time p_0, cell r_2 bears the mark "#", and |
| + | | |
| + | | At the point-in-time p_1, M is in the state q_1, and |
| + | | At the point-in-time p_1, H is on the cell r_2, and |
| + | | At the point-in-time p_1, cell r_0 bears the mark "#", and |
| + | | At the point-in-time p_1, cell r_1 bears the mark "1", and |
| + | | At the point-in-time p_1, cell r_2 bears the mark "#", and |
| + | | |
| + | | At the point-in-time p_2, M is in the state q_*, and |
| + | | At the point-in-time p_2, H is on the cell r_1, and |
| + | | At the point-in-time p_2, cell r_0 bears the mark "#", and |
| + | | At the point-in-time p_2, cell r_1 bears the mark "1", and |
| + | | At the point-in-time p_2, cell r_2 bears the mark "#". |
| + | |
| + | In brief, the output for our sake being the symbol that rests |
| + | under the tape-head H when the machine M gets to a rest state, |
| + | we are now amazed by the remarkable result that Parity(1) = 1. |
| + | |
| + | I realized after sending that last bunch of bits that there is room |
| + | for confusion about what is the input/output of the Study module of |
| + | the Theme One program as opposed to what is the input/output of the |
| + | "finitely approximated turing automaton" (FATA). So here is better |
| + | delineation of what's what. The input to Study is a text file that |
| + | is known as LogFile(Whatever) and the output of Study is a sequence |
| + | of text files that summarize the various canonical and normal forms |
| + | that it generates. For short, let us call these NormFile(Whatelse). |
| + | With that in mind, here are the actual IO's of Study, excluding the |
| + | glosses in square brackets: |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~INPUT~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | [Input To Study = FATA Initial Conditions + FATA Program Conditions] |
| + | |
| + | [FATA Initial Conditions For Input 0] |
| + | |
| + | p0_q0 |
| + | |
| + | p0_r1 |
| + | |
| + | p0_r0_s# |
| + | p0_r1_s0 |
| + | p0_r2_s# |
| + | |
| + | [FATA Program Conditions For Parity Machine] |
| + | |
| + | [Mediate Conditions] |
| + | |
| + | ( p0_q# ( p1_q# )) |
| + | ( p0_q* ( p1_q* )) |
| + | |
| + | ( p1_q# ( p2_q# )) |
| + | ( p1_q* ( p2_q* )) |
| + | |
| + | [Terminal Conditions] |
| + | |
| + | (( p2_q# )( p2_q* )) |
| + | |
| + | [State Partition] |
| + | |
| + | (( p0_q0 ),( p0_q1 ),( p0_q# ),( p0_q* )) |
| + | (( p1_q0 ),( p1_q1 ),( p1_q# ),( p1_q* )) |
| + | (( p2_q0 ),( p2_q1 ),( p2_q# ),( p2_q* )) |
| + | |
| + | [Register Partition] |
| + | |
| + | (( p0_r0 ),( p0_r1 ),( p0_r2 )) |
| + | (( p1_r0 ),( p1_r1 ),( p1_r2 )) |
| + | (( p2_r0 ),( p2_r1 ),( p2_r2 )) |
| + | |
| + | [Symbol Partition] |
| + | |
| + | (( p0_r0_s0 ),( p0_r0_s1 ),( p0_r0_s# )) |
| + | (( p0_r1_s0 ),( p0_r1_s1 ),( p0_r1_s# )) |
| + | (( p0_r2_s0 ),( p0_r2_s1 ),( p0_r2_s# )) |
| + | |
| + | (( p1_r0_s0 ),( p1_r0_s1 ),( p1_r0_s# )) |
| + | (( p1_r1_s0 ),( p1_r1_s1 ),( p1_r1_s# )) |
| + | (( p1_r2_s0 ),( p1_r2_s1 ),( p1_r2_s# )) |
| + | |
| + | (( p2_r0_s0 ),( p2_r0_s1 ),( p2_r0_s# )) |
| + | (( p2_r1_s0 ),( p2_r1_s1 ),( p2_r1_s# )) |
| + | (( p2_r2_s0 ),( p2_r2_s1 ),( p2_r2_s# )) |
| + | |
| + | [Interaction Conditions] |
| + | |
| + | (( p0_r0 ) p0_r0_s0 ( p1_r0_s0 )) |
| + | (( p0_r0 ) p0_r0_s1 ( p1_r0_s1 )) |
| + | (( p0_r0 ) p0_r0_s# ( p1_r0_s# )) |
| + | |
| + | (( p0_r1 ) p0_r1_s0 ( p1_r1_s0 )) |
| + | (( p0_r1 ) p0_r1_s1 ( p1_r1_s1 )) |
| + | (( p0_r1 ) p0_r1_s# ( p1_r1_s# )) |
| + | |
| + | (( p0_r2 ) p0_r2_s0 ( p1_r2_s0 )) |
| + | (( p0_r2 ) p0_r2_s1 ( p1_r2_s1 )) |
| + | (( p0_r2 ) p0_r2_s# ( p1_r2_s# )) |
| + | |
| + | (( p1_r0 ) p1_r0_s0 ( p2_r0_s0 )) |
| + | (( p1_r0 ) p1_r0_s1 ( p2_r0_s1 )) |
| + | (( p1_r0 ) p1_r0_s# ( p2_r0_s# )) |
| + | |
| + | (( p1_r1 ) p1_r1_s0 ( p2_r1_s0 )) |
| + | (( p1_r1 ) p1_r1_s1 ( p2_r1_s1 )) |
| + | (( p1_r1 ) p1_r1_s# ( p2_r1_s# )) |
| + | |
| + | (( p1_r2 ) p1_r2_s0 ( p2_r2_s0 )) |
| + | (( p1_r2 ) p1_r2_s1 ( p2_r2_s1 )) |
| + | (( p1_r2 ) p1_r2_s# ( p2_r2_s# )) |
| + | |
| + | [Transition Relations] |
| + | |
| + | ( p0_q0 p0_r1 p0_r1_s0 ( p1_q0 p1_r2 p1_r1_s0 )) |
| + | ( p0_q0 p0_r1 p0_r1_s1 ( p1_q1 p1_r2 p1_r1_s1 )) |
| + | ( p0_q0 p0_r1 p0_r1_s# ( p1_q# p1_r0 p1_r1_s# )) |
| + | ( p0_q0 p0_r2 p0_r2_s# ( p1_q# p1_r1 p1_r2_s# )) |
| + | |
| + | ( p0_q1 p0_r1 p0_r1_s0 ( p1_q1 p1_r2 p1_r1_s0 )) |
| + | ( p0_q1 p0_r1 p0_r1_s1 ( p1_q0 p1_r2 p1_r1_s1 )) |
| + | ( p0_q1 p0_r1 p0_r1_s# ( p1_q* p1_r0 p1_r1_s# )) |
| + | ( p0_q1 p0_r2 p0_r2_s# ( p1_q* p1_r1 p1_r2_s# )) |
| + | |
| + | ( p1_q0 p1_r1 p1_r1_s0 ( p2_q0 p2_r2 p2_r1_s0 )) |
| + | ( p1_q0 p1_r1 p1_r1_s1 ( p2_q1 p2_r2 p2_r1_s1 )) |
| + | ( p1_q0 p1_r1 p1_r1_s# ( p2_q# p2_r0 p2_r1_s# )) |
| + | ( p1_q0 p1_r2 p1_r2_s# ( p2_q# p2_r1 p2_r2_s# )) |
| + | |
| + | ( p1_q1 p1_r1 p1_r1_s0 ( p2_q1 p2_r2 p2_r1_s0 )) |
| + | ( p1_q1 p1_r1 p1_r1_s1 ( p2_q0 p2_r2 p2_r1_s1 )) |
| + | ( p1_q1 p1_r1 p1_r1_s# ( p2_q* p2_r0 p2_r1_s# )) |
| + | ( p1_q1 p1_r2 p1_r2_s# ( p2_q* p2_r1 p2_r2_s# )) |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~OUTPUT~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | [Output Of Study = FATA Output For Input 0] |
| + | |
| + | p0_q0 |
| + | p0_r1 |
| + | p0_r0_s# |
| + | p0_r1_s0 |
| + | p0_r2_s# |
| + | p1_q0 |
| + | p1_r2 |
| + | p1_r2_s# |
| + | p1_r0_s# |
| + | p1_r1_s0 |
| + | p2_q# |
| + | p2_r1 |
| + | p2_r0_s# |
| + | p2_r1_s0 |
| + | p2_r2_s# |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Turing automata, finitely approximated or not, make my head spin and |
| + | my tape go loopy, and I still believe 'twere a far better thing I do |
| + | if I work up to that level of complexity in a more gracile graduated |
| + | manner. So let us return to our Example in this gradual progress to |
| + | that vastly more well-guarded grail of our long-term pilgrim's quest: |
| + | |
| + | | boy male girl female |
| + | | o---o child o---o child |
| + | | male female \ / \ / child human |
| + | | o---o o o o--o |
| + | | \ / | | | |
| + | | @ @ @ @ |
| + | | |
| + | | (male , female)((boy , male child))((girl , female child))(child (human)) |
| + | |
| + | One section of the Theme One program has a suite of utilities that fall |
| + | under the title "Theme One Study" ("To Study", or just "TOS" for short). |
| + | To Study is to read and to parse a so-called and a generally so-suffixed |
| + | "log" file, and then to conjoin what is called a "query", which is really |
| + | just an additional propositional expression that imposes a further logical |
| + | constraint on the input expression. |
| + | |
| + | The Figure roughly sketches the conjuncts of the graph-theoretic |
| + | data structure that the parser would commit to memory on reading |
| + | the appropriate log file that contains the text along the bottom. |
| + | |
| + | I will now explain the various sorts of things that the TOS utility |
| + | can do with the log file that describes the universe of discourse in |
| + | our present Example. |
| + | |
| + | Theme One Study is built around a suite of four successive generators |
| + | of "normal forms" for propositional expressions, just to use that term |
| + | in a very approximate way. The functions that compute these normal forms |
| + | are called "Model", "Tenor", "Canon", and "Sense", and so we may refer to |
| + | to their text-style outputs as the "mod", "ten", "can", and "sen" files. |
| + | |
| + | Though it could be any propositional expression on the same vocabulary |
| + | $A$ = {"boy", "child", "female", "girl", "human", "male"}, more usually |
| + | the query is a simple conjunction of one or more positive features that |
| + | we want to focus on or perhaps to filter out of the logical model space. |
| + | On our first run through this Example, we take the log file proposition |
| + | as it is, with no extra riders. |
| + | |
| + | | Procedural Note. TO Study Model displays a running tab of how much |
| + | | free memory space it has left. On some of the harder problems that |
| + | | you may think of to give it, Model may run out of free memory and |
| + | | terminate, abnormally exiting Theme One. Sometimes it helps to: |
| + | | |
| + | | 1. Rephrase the problem in logically equivalent |
| + | | but rhetorically increasedly felicitous ways. |
| + | | |
| + | | 2. Think of additional facts that are taken for granted but not |
| + | | made explicit and that cannot be logically inferred by Model. |
| + | |
| + | After Model has finished, it is ready to write out its mod file, |
| + | which you may choose to show on the screen or save to a named file. |
| + | Mod files are usually too long to see (or to care to see) all at once |
| + | on the screen, so it is very often best to save them for later replay. |
| + | In our Example the Model function yields a mod file that looks like so: |
| + | |
| + | Model Output and |
| + | Mod File Example |
| + | o-------------------o |
| + | | male | |
| + | | female - | 1 |
| + | | (female ) | |
| + | | girl - | 2 |
| + | | (girl ) | |
| + | | child | |
| + | | boy | |
| + | | human * | 3 * |
| + | | (human ) - | 4 |
| + | | (boy ) - | 5 |
| + | | (child ) | |
| + | | boy - | 6 |
| + | | (boy ) * | 7 * |
| + | | (male ) | |
| + | | female | |
| + | | boy - | 8 |
| + | | (boy ) | |
| + | | child | |
| + | | girl | |
| + | | human * | 9 * |
| + | | (human ) - | 10 |
| + | | (girl ) - | 11 |
| + | | (child ) | |
| + | | girl - | 12 |
| + | | (girl ) * | 13 * |
| + | | (female ) - | 14 |
| + | o-------------------o |
| + | |
| + | Counting the stars "*" that indicate true interpretations |
| + | and the bars "-" that indicate false interpretations of |
| + | the input formula, we can see that the Model function, |
| + | out of the 64 possible interpretations, has actually |
| + | gone through the work of making just 14 evaluations, |
| + | all in order to find the 4 models that are allowed |
| + | by the input definitions. |
| + | |
| + | To be clear about what this output means, the starred paths |
| + | indicate all of the complete specifications of objects in the |
| + | universe of discourse, that is, all of the consistent feature |
| + | conjunctions of maximum length, as permitted by the definitions |
| + | that are given in the log file. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Let's take a little break from the Example in progress |
| + | and look at where we are and what we have been doing from |
| + | computational, logical, and semiotic perspectives. Because, |
| + | after all, as is usually the case, we should not let our focus |
| + | and our fascination with this particular Example prevent us from |
| + | recognizing it, and all that we do with it, as just an Example of |
| + | much broader paradigms and predicaments and principles, not to say |
| + | but a glimmer of ultimately more concernful and fascinating objects. |
| + | |
| + | I chart the progression that we have just passed through in this way: |
| + | |
| + | | Parse |
| + | | Sign A o-------------->o Sign 1 |
| + | | ^ | |
| + | | / | |
| + | | / | |
| + | | / | |
| + | | Object o | Transform |
| + | | ^ | |
| + | | \ | |
| + | | \ | |
| + | | \ v |
| + | | Sign B o<--------------o Sign 2 |
| + | | Verse |
| + | | |
| + | | Figure. Computation As Sign Transformation |
| + | |
| + | In the present case, the Object is an objective situation |
| + | or a state of affairs, in effect, a particular pattern of |
| + | feature concurrences occurring to us in that world through |
| + | which we find ourselves most frequently faring, wily nily, |
| + | and the Signs are different tokens and different types of |
| + | data structures that we somehow or other find it useful |
| + | to devise or to discover for the sake of representing |
| + | current objects to ourselves on a recurring basis. |
| + | |
| + | But not all signs, not even signs of a single object, are alike |
| + | in every other respect that one might name, not even with respect |
| + | to their powers of relating, significantly, to that common object. |
| + | |
| + | And that is what our whole business of computation busies itself about, |
| + | when it minds its business best, that is, transmuting signs into signs |
| + | in ways that augment their powers of relating significantly to objects. |
| + | |
| + | We have seen how the Model function and the mod output format |
| + | indicate all of the complete specifications of objects in the |
| + | universe of discourse, that is, all of the consistent feature |
| + | conjunctions of maximal specificity that are permitted by the |
| + | constraints or the definitions that are given in the log file. |
| + | |
| + | To help identify these specifications of particular cells in |
| + | the universe of discourse, the next function and output format, |
| + | called "Tenor", edits the mod file to give only the true paths, |
| + | in effect, the "positive models", that are by default what we |
| + | usually mean when we say "models", and not the "anti-models" |
| + | or the "negative models" that fail to satisfy the formula |
| + | in question. |
| + | |
| + | In the present Example the Tenor function |
| + | generates a Ten file that looks like this: |
| + | |
| + | Tenor Output and |
| + | Ten File Example |
| + | o-------------------o |
| + | | male | |
| + | | (female ) | |
| + | | (girl ) | |
| + | | child | |
| + | | boy | |
| + | | human * | <1> |
| + | | (child ) | |
| + | | (boy ) * | <2> |
| + | | (male ) | |
| + | | female | |
| + | | (boy ) | |
| + | | child | |
| + | | girl | |
| + | | human * | <3> |
| + | | (child ) | |
| + | | (girl ) * | <4> |
| + | o-------------------o |
| + | |
| + | As I said, the Tenor function just abstracts a transcript of the models, |
| + | that is, the satisfying interpretations, that were already interspersed |
| + | throughout the complete Model output. These specifications, or feature |
| + | conjunctions, with the positive and the negative features listed in the |
| + | order of their actual budding on the "arboreal boolean expansion" twigs, |
| + | may be gathered and arranged in this antherypulogical flowering bouquet: |
| + | |
| + | 1. male (female ) (girl ) child boy human * |
| + | 2. male (female ) (girl ) (child ) (boy ) * |
| + | 3. (male ) female (boy ) child girl human * |
| + | 4. (male ) female (boy ) (child ) (girl ) * |
| + | |
| + | Notice that Model, as reflected in this abstract, did not consider |
| + | the six positive features in the same order along each path. This |
| + | is because the algorithm was designed to proceed opportunistically |
| + | in its attempt to reduce the original proposition through a series |
| + | of case-analytic considerations and the resulting simplifications. |
| + | |
| + | Notice, too, that Model is something of a lazy evaluator, quitting work |
| + | when and if a value is determined by less than the full set of variables. |
| + | This is the reason why paths <2> and <4> are not ostensibly of the maximum |
| + | length. According to this lazy mode of understanding, any path that is not |
| + | specified on a set of features really stands for the whole bundle of paths |
| + | that are derived by freely varying those features. Thus, specifications |
| + | <2> and <4> summarize four models altogether, with the logical choice |
| + | between "human" and "not human" being left open at the point where |
| + | they leave off their branches in the releavent deciduous tree. |
| + | |
| + | The last two functions in the Study section, "Canon" and "Sense", |
| + | extract further derivatives of the normal forms that are produced |
| + | by Model and Tenor. Both of these functions take the set of model |
| + | paths and simply throw away the negative labels. You may think of |
| + | these as the "rose colored glasses" or "job interview" normal forms, |
| + | in that they try to say everything that's true, so long as it can be |
| + | expressed in positive terms. Generally, this would mean losing a lot |
| + | of information, and the result could no longer be expected to have the |
| + | property of remaining logically equivalent to the original proposition. |
| + | |
| + | Fortunately, however, it seems that this type of positive projection of |
| + | the whole truth is just what is possible, most needed, and most clear in |
| + | many of the "natural" examples, that is, in examples that arise from the |
| + | domains of natural language and natural conceptual kinds. In these cases, |
| + | where most of the logical features are redundantly coded, for example, in |
| + | the way that "adult" = "not child" and "child" = "not adult", the positive |
| + | feature bearing redacts are often sufficiently expressive all by themselves. |
| + | |
| + | Canon merely censors its printing of the negative labels as it traverses the |
| + | model tree. This leaves the positive labels in their original columns of the |
| + | outline form, giving it a slightly skewed appearance. This can be misleading |
| + | unless you already know what you are looking for. However, this Canon format |
| + | is computationally quick, and frequently suffices, especially if you already |
| + | have a likely clue about what to expect in the way of a question's outcome. |
| + | |
| + | In the present Example the Canon function |
| + | generates a Can file that looks like this: |
| + | |
| + | Canon Output and |
| + | Can File Example |
| + | o-------------------o |
| + | | male | |
| + | | child | |
| + | | boy | |
| + | | human | |
| + | | female | |
| + | | child | |
| + | | girl | |
| + | | human | |
| + | o-------------------o |
| + | |
| + | The Sense function does the extra work that is required |
| + | to place the positive labels of the model tree at their |
| + | proper level in the outline. |
| + | |
| + | In the present Example the Sense function |
| + | generates a Sen file that looks like this: |
| + | |
| + | Sense Output and |
| + | Sen File Example |
| + | o-------------------o |
| + | | male | |
| + | | child | |
| + | | boy | |
| + | | human | |
| + | | female | |
| + | | child | |
| + | | girl | |
| + | | human | |
| + | o-------------------o |
| + | |
| + | The Canon and Sense outlines for this Example illustrate a certain |
| + | type of general circumstance that needs to be noted at this point. |
| + | Recall the model paths or the feature specifications that were |
| + | numbered <2> and <4> in the listing of the output for Tenor. |
| + | These paths, in effect, reflected Model's discovery that |
| + | the venn diagram cells for male or female non-children |
| + | and male or female non-humans were not excluded by |
| + | the definitions that were given in the Log file. |
| + | In the abstracts given by Canon and Sense, the |
| + | specifications <2> and <4> have been subsumed, |
| + | or absorbed unmarked, under the general topics |
| + | of their respective genders, male or female. |
| + | This happens because no purely positive |
| + | features were supplied to distinguish |
| + | the non-child and non-human cases. |
| + | |
| + | That completes the discussion of |
| + | this six-dimensional Example. |
| + | |
| + | Nota Bene, for possible future use. In the larger current of work |
| + | with respect to which this meander of a conduit was initially both |
| + | diversionary and tributary, before those high and dry regensquirm |
| + | years when it turned into an intellectual interglacial oxbow lake, |
| + | I once had in mind a scape in which expressions in a definitional |
| + | lattice were ordered according to their simplicity on some scale |
| + | or another, and in this setting the word "sense" was actually an |
| + | acronym for "semantically equivalent next-simplest expression". |
| + | |
| + | | If this is starting to sound a little bit familiar, |
| + | | it may be because the relationship between the two |
| + | | kinds of pictures of propositions, namely: |
| + | | |
| + | | 1. Propositions about things in general, here, |
| + | | about the times when certain facts are true, |
| + | | having the form of functions f : X -> B, |
| + | | |
| + | | 2. Propositions about binary codes, here, about |
| + | | the bit-vector labels on venn diagram cells, |
| + | | having the form of functions f' : B^k -> B, |
| + | | |
| + | | is an epically old story, one that I, myself, |
| + | | have related one or twice upon a time before, |
| + | | to wit, at least, at the following two cites: |
| + | | |
| + | | http://suo.ieee.org/email/msg01251.html |
| + | | http://suo.ieee.org/email/msg01293.html |
| + | | |
| + | | There, and now here, once more, and again, it may be observed |
| + | | that the relation is one whereby the proposition f : X -> B, |
| + | | the one about things and times and mores in general, factors |
| + | | into a coding function c : X -> B^k, followed by a derived |
| + | | proposition f' : B^k -> B that judges the resulting codes. |
| + | | |
| + | | f |
| + | | X o------>o B |
| + | | \ ^ |
| + | | c = <x_1, ..., x_k> \ / f' |
| + | | v / |
| + | | o |
| + | | B^k |
| + | | |
| + | | You may remember that this was supposed to illustrate |
| + | | the "factoring" of a proposition f : X -> B = {0, 1} |
| + | | into the composition f'(c(x)), where c : X -> B^k is |
| + | | the "coding" of each x in X as an k-bit string in B^k, |
| + | | and where f' is the mapping of codes into a co-domain |
| + | | that we interpret as t-f-values, B = {0, 1} = {F, T}. |
| + | |
| + | In short, there is the standard equivocation ("systematic ambiguity"?) as to |
| + | whether we are talking about the "applied" and concretely typed proposition |
| + | f : X -> B or the "pure" and abstractly typed proposition f' : B^k -> B. |
| + | Or we can think of the latter object as the approximate code icon of |
| + | the former object. |
| + | |
| + | Anyway, these types of formal objects are the sorts of things that |
| + | I take to be the denotational objects of propositional expressions. |
| + | These objects, along with their invarious and insundry mathematical |
| + | properties, are the orders of things that I am talking about when |
| + | I refer to the "invariant structures in these objects themselves". |
| + | |
| + | "Invariant" means "invariant under a suitable set of transformations", |
| + | in this case the translations between various languages that preserve |
| + | the objects and the structures in question. In extremest generality, |
| + | this is what universal constructions in category theory are all about. |
| + | |
| + | In summation, the functions f : X -> B and f' : B* -> B have invariant, formal, |
| + | mathematical, objective properties that any adequate language might eventually |
| + | evolve to express, only some languages express them more obscurely than others. |
| + | |
| + | To be perfectly honest, I continue to be surprised that anybody in this group |
| + | has trouble with this. There are perfectly apt and familiar examples in the |
| + | contrast between roman numerals and arabic numerals, or the contrast between |
| + | redundant syntaxes, like those that use the pentalphabet {~, &, v, =>, <=>}, |
| + | and trimmer syntaxes, like those used in existential and conceptual graphs. |
| + | Every time somebody says "Let's take {~, &, v, =>, <=>} as an operational |
| + | basis for logic" it's just like that old joke that mathematicians tell on |
| + | engineers where the ingenue in question says "1 is a prime, 2 is a prime, |
| + | 3 is a prime, 4 is a prime, ..." -- and I know you think that I'm being |
| + | hyperbolic, but I'm really only up to parabolas here ... |
| + | |
| + | I have already refined my criticism so that it does not apply to |
| + | the spirit of FOL or KIF or whatever, but only to the letters of |
| + | specific syntactic proposals. There is a fact of the matter as |
| + | to whether a concrete language provides a clean or a cluttered |
| + | basis for representing the identified set of formal objects. |
| + | And it shows up in pragmatic realities like the efficiency |
| + | of real time concept formation, concept use, learnability, |
| + | reasoning power, and just plain good use of real time. |
| + | These are the dire consequences that I learned in my |
| + | very first tries at mathematically oriented theorem |
| + | automation, and the only factor that has obscured |
| + | them in mainstream work since then is the speed |
| + | with which folks can now do all of the same |
| + | old dumb things that they used to do on |
| + | their way to kludging out the answers. |
| + | |
| + | It seems to be darn near impossible to explain to the |
| + | centurion all of the neat stuff that he's missing by |
| + | sticking to his old roman numerals. He just keeps |
| + | on reckoning that what he can't count must be of |
| + | no account at all. There is way too much stuff |
| + | that these original syntaxes keep us from even |
| + | beginning to discuss, like differential logic, |
| + | just for starters. |
| + | |
| + | Our next Example illustrates the use of the Cactus Language |
| + | for representing "absolute" and "relative" partitions, also |
| + | known as "complete" and "contingent" classifications of the |
| + | universe of discourse, all of which amounts to divvying it |
| + | up into mutually exclusive regions, exhaustive or not, as |
| + | one frequently needs in situations involving a genus and |
| + | its sundry species, and frequently pictures in the form |
| + | of a venn diagram that looks just like a "pie chart". |
| + | |
| + | Example. Partition, Genus & Species |
| + | |
| + | The idea that one needs for expressing partitions |
| + | in cactus expressions can be summed up like this: |
| + | |
| + | | If the propositional expression |
| + | | |
| + | | "( p , q , r , ... )" |
| + | | |
| + | | means that just one of |
| + | | |
| + | | p, q, r, ... is false, |
| + | | |
| + | | then the propositional expression |
| + | | |
| + | | "((p),(q),(r), ... )" |
| + | | |
| + | | must mean that just one of |
| + | | |
| + | | (p), (q), (r), ... is false, |
| + | | |
| + | | in other words, that just one of |
| + | | |
| + | | p, q, r, ... is true. |
| + | |
| + | Thus we have an efficient means to express and to enforce |
| + | a partition of the space of models, in effect, to maintain |
| + | the condition that a number of features or propositions are |
| + | to be held in mutually exclusive and exhaustive disjunction. |
| + | This supplies a much needed bridge between the binary domain |
| + | of two values and any other domain with a finite number of |
| + | feature values. |
| + | |
| + | Another variation on this theme allows one to maintain the |
| + | subsumption of many separate species under an explicit genus. |
| + | To see this, let us examine the following form of expression: |
| + | |
| + | ( q , ( q_1 ) , ( q_2 ) , ( q_3 ) ). |
| + | |
| + | Now consider what it would mean for this to be true. We see two cases: |
| + | |
| + | 1. If the proposition q is true, then exactly one of the |
| + | propositions (q_1), (q_2), (q_3) must be false, and so |
| + | just one of the propositions q_1, q_2, q_3 must be true. |
| + | |
| + | 2. If the proposition q is false, then every one of the |
| + | propositions (q_1), (q_2), (q_2) must be true, and so |
| + | each one of the propositions q_1, q_2, q_3 must be false. |
| + | In short, if q is false then all of the other q's are also. |
| + | |
| + | Figures 1 and 2 illustrate this type of situation. |
| + | |
| + | Figure 1 is the venn diagram of a 4-dimensional universe of discourse |
| + | X = [q, q_1, q_2, q_3], conventionally named after the gang of four |
| + | logical features that generate it. Strictly speaking, X is made up |
| + | of two layers, the position space X of abstract type %B%^4, and the |
| + | proposition space X^ = (X -> %B%) of abstract type %B%^4 -> %B%, |
| + | but it is commonly lawful enough to sign the signature of both |
| + | spaces with the same X, and thus to give the power of attorney |
| + | for the propositions to the so-indicted position space thereof. |
| + | |
| + | Figure 1 also makes use of the convention whereby the regions |
| + | or the subsets of the universe of discourse that correspond |
| + | to the basic features q, q_1, q_2, q_3 are labelled with |
| + | the parallel set of upper case letters Q, Q_1, Q_2, Q_3. |
| + | |
| + | | o |
| + | | / \ |
| + | | / \ |
| + | | / \ |
| + | | / \ |
| + | | o o |
| + | | /%\ /%\ |
| + | | /%%%\ /%%%\ |
| + | | /%%%%%\ /%%%%%\ |
| + | | /%%%%%%%\ /%%%%%%%\ |
| + | | o%%%%%%%%%o%%%%%%%%%o |
| + | | / \%%%%%%%/ \%%%%%%%/ \ |
| + | | / \%%%%%/ \%%%%%/ \ |
| + | | / \%%%/ \%%%/ \ |
| + | | / \%/ \%/ \ |
| + | | o o o o |
| + | | / \ /%\ / \ / \ |
| + | | / \ /%%%\ / \ / \ |
| + | | / \ /%%%%%\ / \ / \ |
| + | | / \ /%%%%%%%\ / \ / \ |
| + | | o o%%%%%%%%%o o o |
| + | | ·\ / \%%%%%%%/ \ / \ /· |
| + | | · \ / \%%%%%/ \ / \ / · |
| + | | · \ / \%%%/ \ / \ / · |
| + | | · \ / \%/ \ / \ / · |
| + | | · o o o o · |
| + | | · ·\ / \ / \ /· · |
| + | | · · \ / \ / \ / · · |
| + | | · · \ / \ / \ / · · |
| + | | · Q · \ / \ / \ / ·Q_3 · |
| + | | ··········o o o·········· |
| + | | · \ /%\ / · |
| + | | · \ /%%%\ / · |
| + | | · \ /%%%%%\ / · |
| + | | · Q_1 \ /%%%%%%%\ / Q_2 · |
| + | | ··········o%%%%%%%%%o·········· |
| + | | \%%%%%%%/ |
| + | | \%%%%%/ |
| + | | \%%%/ |
| + | | \%/ |
| + | | o |
| + | | |
| + | | Figure 1. Genus Q and Species Q_1, Q_2, Q_3 |
| + | |
| + | Figure 2 is another form of venn diagram that one often uses, |
| + | where one collapses the unindited cells and leaves only the |
| + | models of the proposition in question. Some people would |
| + | call the transformation that changes from the first form |
| + | to the next form an operation of "taking the quotient", |
| + | but I tend to think of it as the "soap bubble picture" |
| + | or more exactly the "wire & thread & soap film" model |
| + | of the universe of discourse, where one pops out of |
| + | consideration the sections of the soap film that |
| + | stretch across the anti-model regions of space. |
| + | |
| + | o-------------------------------------------------o |
| + | | | |
| + | | X | |
| + | | | |
| + | | o | |
| + | | / \ | |
| + | | / \ | |
| + | | / \ | |
| + | | / \ | |
| + | | / \ | |
| + | | o Q_1 o | |
| + | | / \ / \ | |
| + | | / \ / \ | |
| + | | / \ / \ | |
| + | | / \ / \ | |
| + | | / \ / \ | |
| + | | / Q \ | |
| + | | / | \ | |
| + | | / | \ | |
| + | | / Q_2 | Q_3 \ | |
| + | | / | \ | |
| + | | / | \ | |
| + | | o-----------------o-----------------o | |
| + | | | |
| + | | | |
| + | | | |
| + | o-------------------------------------------------o |
| + | |
| + | Figure 2. Genus Q and Species Q_1, Q_2, Q_3 |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Example. Partition, Genus & Species (cont.) |
| + | |
| + | Last time we considered in general terms how the forms |
| + | of complete partition and contingent partition operate |
| + | to maintain mutually disjoint and possibly exhaustive |
| + | categories of positions in a universe of discourse. |
| + | |
| + | This time we contemplate another concrete Example of |
| + | near minimal complexity, designed to demonstrate how |
| + | the forms of partition and subsumption can interact |
| + | in structuring a space of feature specifications. |
| + | |
| + | In this Example, we describe a universe of discourse |
| + | in terms of the following vocabulary of five features: |
| + | |
| + | | L. living_thing |
| + | | |
| + | | N. non_living |
| + | | |
| + | | A. animal |
| + | | |
| + | | V. vegetable |
| + | | |
| + | | M. mineral |
| + | |
| + | Let us construe these features as being subject to four constraints: |
| + | |
| + | | 1. Everything is either a living_thing or non_living, but not both. |
| + | | |
| + | | 2. Everything is either animal, vegetable, or mineral, |
| + | | but no two of these together. |
| + | | |
| + | | 3. A living_thing is either animal or vegetable, but not both, |
| + | | and everything animal or vegetable is a living_thing. |
| + | | |
| + | | 4. Everything mineral is non_living. |
| + | |
| + | These notions and constructions are expressed in the Log file shown below: |
| + | |
| + | Logical Input File |
| + | o-------------------------------------------------o |
| + | | | |
| + | | ( living_thing , non_living ) | |
| + | | | |
| + | | (( animal ),( vegetable ),( mineral )) | |
| + | | | |
| + | | ( living_thing ,( animal ),( vegetable )) | |
| + | | | |
| + | | ( mineral ( non_living )) | |
| + | | | |
| + | o-------------------------------------------------o |
| + | |
| + | The cactus expression in this file is the expression |
| + | of a "zeroth order theory" (ZOT), one that can be |
| + | paraphrased in more ordinary language to say: |
| + | |
| + | Translation |
| + | o-------------------------------------------------o |
| + | | | |
| + | | living_thing =/= non_living | |
| + | | | |
| + | | par : all -> {animal, vegetable, mineral} | |
| + | | | |
| + | | par : living_thing -> {animal, vegetable} | |
| + | | | |
| + | | mineral => non_living | |
| + | | | |
| + | o-------------------------------------------------o |
| + | |
| + | Here, "par : all -> {p, q, r}" is short for an assertion |
| + | that the universe as a whole is partitioned into subsets |
| + | that correspond to the features p, q, r. |
| + | |
| + | Also, "par : q -> {r, s}" asserts that "Q partitions into R and S. |
| + | |
| + | It is probably enough just to list the outputs of Model, Tenor, and Sense |
| + | when run on the preceding Log file. Using the same format and labeling as |
| + | before, we may note that Model has, from 2^5 = 32 possible interpretations, |
| + | made 11 evaluations, and found 3 models answering the generic descriptions |
| + | that were imposed by the logical input file. |
| + | |
| + | Model Outline |
| + | o------------------------o |
| + | | living_thing | |
| + | | non_living - | 1 |
| + | | (non_living ) | |
| + | | mineral - | 2 |
| + | | (mineral ) | |
| + | | animal | |
| + | | vegetable - | 3 |
| + | | (vegetable ) * | 4 * |
| + | | (animal ) | |
| + | | vegetable * | 5 * |
| + | | (vegetable ) - | 6 |
| + | | (living_thing ) | |
| + | | non_living | |
| + | | animal - | 7 |
| + | | (animal ) | |
| + | | vegetable - | 8 |
| + | | (vegetable ) | |
| + | | mineral * | 9 * |
| + | | (mineral ) - | 10 |
| + | | (non_living ) - | 11 |
| + | o------------------------o |
| + | |
| + | Tenor Outline |
| + | o------------------------o |
| + | | living_thing | |
| + | | (non_living ) | |
| + | | (mineral ) | |
| + | | animal | |
| + | | (vegetable ) * | <1> |
| + | | (animal ) | |
| + | | vegetable * | <2> |
| + | | (living_thing ) | |
| + | | non_living | |
| + | | (animal ) | |
| + | | (vegetable ) | |
| + | | mineral * | <3> |
| + | o------------------------o |
| + | |
| + | Sense Outline |
| + | o------------------------o |
| + | | living_thing | |
| + | | animal | |
| + | | vegetable | |
| + | | non_living | |
| + | | mineral | |
| + | o------------------------o |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Example. Molly's World |
| + | |
| + | I think that we are finally ready to tackle a more respectable example. |
| + | The Example known as "Molly's World" is borrowed from the literature on |
| + | computational learning theory, adapted with a few changes from the example |
| + | called "Molly’s Problem" in the paper "Learning With Hints" by Dana Angluin. |
| + | By way of setting up the problem, I quote Angluin's motivational description: |
| + | |
| + | | Imagine that you have become acquainted with an alien named Molly from the |
| + | | planet Ornot, who is currently employed in a day-care center. She is quite |
| + | | good at propositional logic, but a bit weak on knowledge of Earth. So you |
| + | | decide to formulate the beginnings of a propositional theory to help her |
| + | | label things in her immediate environment. |
| + | | |
| + | | Angluin, Dana, "Learning With Hints", pages 167-181, in: |
| + | | David Haussler & Leonard Pitt (eds.), 'Proceedings of the 1988 Workshop |
| + | | on Computational Learning Theory', Morgan Kaufmann, San Mateo, CA, 1989. |
| + | |
| + | The purpose of this quaint pretext is, of course, to make sure that the |
| + | reader appreciates the constraints of the problem: that no extra savvy |
| + | is fair, all facts must be presumed or deduced on the immediate premises. |
| + | |
| + | My use of this example is not directly relevant to the purposes of the |
| + | discussion from which it is taken, so I simply give my version of it |
| + | without comment on those issues. |
| + | |
| + | Here is my rendition of the initial knowledge base delimiting Molly’s World: |
| + | |
| + | Logical Input File: Molly.Log |
| + | o---------------------------------------------------------------------o |
| + | | | |
| + | | ( object ,( toy ),( vehicle )) | |
| + | | (( small_size ),( medium_size ),( large_size )) | |
| + | | (( two_wheels ),( three_wheels ),( four_wheels )) | |
| + | | (( no_seat ),( one_seat ),( few_seats ),( many_seats )) | |
| + | | ( object ,( scooter ),( bike ),( trike ),( car ),( bus ),( wagon )) | |
| + | | ( two_wheels no_seat ,( scooter )) | |
| + | | ( two_wheels one_seat pedals ,( bike )) | |
| + | | ( three_wheels one_seat pedals ,( trike )) | |
| + | | ( four_wheels few_seats doors ,( car )) | |
| + | | ( four_wheels many_seats doors ,( bus )) | |
| + | | ( four_wheels no_seat handle ,( wagon )) | |
| + | | ( scooter ( toy small_size )) | |
| + | | ( wagon ( toy small_size )) | |
| + | | ( trike ( toy small_size )) | |
| + | | ( bike small_size ( toy )) | |
| + | | ( bike medium_size ( vehicle )) | |
| + | | ( bike large_size ) | |
| + | | ( car ( vehicle large_size )) | |
| + | | ( bus ( vehicle large_size )) | |
| + | | ( toy ( object )) | |
| + | | ( vehicle ( object )) | |
| + | | | |
| + | o---------------------------------------------------------------------o |
| + | |
| + | All of the logical forms that are used in the preceding Log file |
| + | will probably be familiar from earlier discussions. The purpose |
| + | of one or two constructions may, however, be a little obscure, |
| + | so I will insert a few words of additional explanation here: |
| + | |
| + | The rule "( bike large_size )", for example, merely |
| + | says that nothing can be both a bike and large_size. |
| + | |
| + | The rule "( three_wheels one_seat pedals ,( trike ))" says that anything |
| + | with all the features of three_wheels, one_seat, and pedals is excluded |
| + | from being anything but a trike. In short, anything with just those |
| + | three features is equivalent to a trike. |
| + | |
| + | Recall that the form "( p , q )" may be interpreted to assert either |
| + | the exclusive disjunction or the logical inequivalence of p and q. |
| + | |
| + | The rules have been stated in this particular way simply |
| + | to imitate the style of rules in the reference example. |
| + | |
| + | This last point does bring up an important issue, the question |
| + | of "rhetorical" differences in expression and their potential |
| + | impact on the "pragmatics" of computation. Unfortunately, |
| + | I will have to abbreviate my discussion of this topic for |
| + | now, and only mention in passing the following facts. |
| + | |
| + | Logically equivalent expressions, even though they must lead |
| + | to logically equivalent normal forms, may have very different |
| + | characteristics when it comes to the efficiency of processing. |
| + | |
| + | For instance, consider the following four forms: |
| + | |
| + | | 1. (( p , q )) |
| + | | |
| + | | 2. ( p ,( q )) |
| + | | |
| + | | 3. (( p ), q ) |
| + | | |
| + | | 4. (( p , q )) |
| + | |
| + | All of these are equally succinct ways of maintaining that |
| + | p is logically equivalent to q, yet each can have different |
| + | effects on the route that Model takes to arrive at an answer. |
| + | Apparently, some equalities are more equal than others. |
| + | |
| + | These effects occur partly because the algorithm chooses to make cases |
| + | of variables on a basis of leftmost shallowest first, but their impact |
| + | can be complicated by the interactions that each expression has with |
| + | the context that it occupies. The main lesson to take away from all |
| + | of this, at least, for the time being, is that it is probably better |
| + | not to bother too much about these problems, but just to experiment |
| + | with different ways of expressing equivalent pieces of information |
| + | until you get a sense of what works best in various situations. |
| + | |
| + | I think that you will be happy to see only the |
| + | ultimate Sense of Molly’s World, so here it is: |
| + | |
| + | Sense Outline: Molly.Sen |
| + | o------------------------o |
| + | | object | |
| + | | two_wheels | |
| + | | no_seat | |
| + | | scooter | |
| + | | toy | |
| + | | small_size | |
| + | | one_seat | |
| + | | pedals | |
| + | | bike | |
| + | | small_size | |
| + | | toy | |
| + | | medium_size | |
| + | | vehicle | |
| + | | three_wheels | |
| + | | one_seat | |
| + | | pedals | |
| + | | trike | |
| + | | toy | |
| + | | small_size | |
| + | | four_wheels | |
| + | | few_seats | |
| + | | doors | |
| + | | car | |
| + | | vehicle | |
| + | | large_size | |
| + | | many_seats | |
| + | | doors | |
| + | | bus | |
| + | | vehicle | |
| + | | large_size | |
| + | | no_seat | |
| + | | handle | |
| + | | wagon | |
| + | | toy | |
| + | | small_size | |
| + | o------------------------o |
| + | |
| + | This outline is not the Sense of the unconstrained Log file, |
| + | but the result of running Model with a query on the single |
| + | feature "object". Using this focus helps the Modeler |
| + | to make more relevant Sense of Molly’s World. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | DM = Douglas McDavid |
| + | |
| + | DM: This, again, is an example of how real issues of ontology are |
| + | so often trivialized at the expense of technicalities. I just |
| + | had a burger, some fries, and a Coke. I would say all that was |
| + | non-living and non-mineral. A virus, I believe is non-animal, |
| + | non-vegetable, but living (and non-mineral). Teeth, shells, |
| + | and bones are virtually pure mineral, but living. These are |
| + | the kinds of issues that are truly "ontological," in my |
| + | opinion. You are not the only one to push them into |
| + | the background as of lesser importance. See the |
| + | discussion of "18-wheelers" in John Sowa's book. |
| + | |
| + | it's not my example, and from you say, it's not your example either. |
| + | copied it out of a book or a paper somewhere, too long ago to remember. |
| + | i am assuming that the author or tardition from which it came must have |
| + | seen some kind of sense in it. tell you what, write out your own theory |
| + | of "what is" in so many variables, more or less, publish it in a book or |
| + | a paper, and then folks will tell you that they dispute each and every |
| + | thing that you have just said, and it won't really matter all that much |
| + | how complex it is or how subtle you are. that has been the way of all |
| + | ontology for about as long as anybody can remember or even read about. |
| + | me? i don't have sufficient arrogance to be an ontologist, and you |
| + | know that's saying a lot, as i can't even imagine a way to convince |
| + | myself that i believe i know "what is", really and truly for sure |
| + | like some folks just seem to do. so i am working to improve our |
| + | technical ability to do logic, which is mostly a job of shooting |
| + | down the more serious delusions that we often get ourselves into. |
| + | can i be of any use to ontologists? i dunno. i guess it depends |
| + | on how badly they are attached to some of the delusions of knowing |
| + | what their "common" sense tells them everybody ought to already know, |
| + | but that every attempt to check that out in detail tells them it just |
| + | ain't so. a problem for which denial was just begging to be invented, |
| + | and so it was. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Example. Molly's World (cont.) |
| + | |
| + | In preparation for a contingently possible future discussion, |
| + | I need to attach a few parting thoughts to the case workup |
| + | of Molly's World that may not seem terribly relevant to |
| + | the present setting, but whose pertinence I hope will |
| + | become clearer in time. |
| + | |
| + | The logical paradigm from which this Example was derived is that |
| + | of "Zeroth Order Horn Clause Theories". The clauses at issue |
| + | in these theories are allowed to be of just three kinds: |
| + | |
| + | | 1. p & q & r & ... => z |
| + | | |
| + | | 2. z |
| + | | |
| + | | 3. ~[p & q & r & ...] |
| + | |
| + | Here, the proposition letters "p", "q", "r", ..., "z" |
| + | are restricted to being single positive features, not |
| + | themselves negated or otherwise complex expressions. |
| + | |
| + | In the Cactus Language or Existential Graph syntax |
| + | these forms would take on the following appearances: |
| + | |
| + | | 1. ( p q r ... ( z )) |
| + | | |
| + | | 2. z |
| + | | |
| + | | 3. ( p q r ... ) |
| + | |
| + | The style of deduction in Horn clause logics is essentially |
| + | proof-theoretic in character, with the main burden of proof |
| + | falling on implication relations ("=>") and on "projective" |
| + | forms of inference, that is, information-losing inferences |
| + | like modus ponens and resolution. Cf. [Llo], [MaW]. |
| + | |
| + | In contrast, the method used here is substantially model-theoretic, |
| + | the stress being to start from more general forms of expression for |
| + | laying out facts (for example, distinctions, equations, partitions) |
| + | and to work toward results that maintain logical equivalence with |
| + | their origins. |
| + | |
| + | What all of this has to do with the output above is this: |
| + | >From the perspective that is adopted in the present work, |
| + | almost any theory, for example, the one that is founded |
| + | on the postulates of Molly's World, will have far more |
| + | models than the implicational and inferential mode of |
| + | reasoning is designed to discover. We will be forced |
| + | to confront them, however, if we try to run Model on |
| + | a large set of implications. |
| + | |
| + | The typical Horn clause interpreter gets around this |
| + | difficulty only by a stratagem that takes clauses to |
| + | mean something other than what they say, that is, by |
| + | distorting the principles of semantics in practice. |
| + | Our Model, on the other hand, has no such finesse. |
| + | |
| + | This explains why it was necessary to impose the |
| + | prerequisite "object" constraint on the Log file |
| + | for Molly's World. It supplied no more than what |
| + | we usually take for granted, in order to obtain |
| + | a set of models that we would normally think of |
| + | as being the intended import of the definitions. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Example. Jets & Sharks |
| + | |
| + | The propositional calculus based on the boundary operator, that is, |
| + | the multigrade logical connective of the form "( , , , ... )" can be |
| + | interpreted in a way that resembles the logic of activation states and |
| + | competition constraints in certain neural network models. One way to do |
| + | this is by interpreting the blank or unmarked state as the resting state |
| + | of a neural pool, the bound or marked state as its activated state, and |
| + | by representing a mutually inhibitory pool of neurons p, q, r by means |
| + | of the expression "( p , q , r )". To illustrate this possibility, |
| + | I transcribe into cactus language expressions a notorious example |
| + | from the "parallel distributed processing" (PDP) paradigm [McR] |
| + | and work through two of the associated exercises as portrayed |
| + | in this format. |
| + | |
| + | Logical Input File: JAS = ZOT(Jets And Sharks) |
| + | o----------------------------------------------------------------o |
| + | | | |
| + | | (( art ),( al ),( sam ),( clyde ),( mike ), | |
| + | | ( jim ),( greg ),( john ),( doug ),( lance ), | |
| + | | ( george ),( pete ),( fred ),( gene ),( ralph ), | |
| + | | ( phil ),( ike ),( nick ),( don ),( ned ),( karl ), | |
| + | | ( ken ),( earl ),( rick ),( ol ),( neal ),( dave )) | |
| + | | | |
| + | | ( jets , sharks ) | |
| + | | | |
| + | | ( jets , | |
| + | | ( art ),( al ),( sam ),( clyde ),( mike ), | |
| + | | ( jim ),( greg ),( john ),( doug ),( lance ), | |
| + | | ( george ),( pete ),( fred ),( gene ),( ralph )) | |
| + | | | |
| + | | ( sharks , | |
| + | | ( phil ),( ike ),( nick ),( don ),( ned ),( karl ), | |
| + | | ( ken ),( earl ),( rick ),( ol ),( neal ),( dave )) | |
| + | | | |
| + | | (( 20's ),( 30's ),( 40's )) | |
| + | | | |
| + | | ( 20's , | |
| + | | ( sam ),( jim ),( greg ),( john ),( lance ), | |
| + | | ( george ),( pete ),( fred ),( gene ),( ken )) | |
| + | | | |
| + | | ( 30's , | |
| + | | ( al ),( mike ),( doug ),( ralph ), | |
| + | | ( phil ),( ike ),( nick ),( don ), | |
| + | | ( ned ),( rick ),( ol ),( neal ),( dave )) | |
| + | | | |
| + | | ( 40's , | |
| + | | ( art ),( clyde ),( karl ),( earl )) | |
| + | | | |
| + | | (( junior_high ),( high_school ),( college )) | |
| + | | | |
| + | | ( junior_high , | |
| + | | ( art ),( al ),( clyde ),( mike ),( jim ), | |
| + | | ( john ),( lance ),( george ),( ralph ),( ike )) | |
| + | | | |
| + | | ( high_school , | |
| + | | ( greg ),( doug ),( pete ),( fred ),( nick ), | |
| + | | ( karl ),( ken ),( earl ),( rick ),( neal ),( dave )) | |
| + | | | |
| + | | ( college , | |
| + | | ( sam ),( gene ),( phil ),( don ),( ned ),( ol )) | |
| + | | | |
| + | | (( single ),( married ),( divorced )) | |
| + | | | |
| + | | ( single , | |
| + | | ( art ),( sam ),( clyde ),( mike ), | |
| + | | ( doug ),( pete ),( fred ),( gene ), | |
| + | | ( ralph ),( ike ),( nick ),( ken ),( neal )) | |
| + | | | |
| + | | ( married , | |
| + | | ( al ),( greg ),( john ),( lance ),( phil ), | |
| + | | ( don ),( ned ),( karl ),( earl ),( ol )) | |
| + | | | |
| + | | ( divorced , | |
| + | | ( jim ),( george ),( rick ),( dave )) | |
| + | | | |
| + | | (( bookie ),( burglar ),( pusher )) | |
| + | | | |
| + | | ( bookie , | |
| + | | ( sam ),( clyde ),( mike ),( doug ), | |
| + | | ( pete ),( ike ),( ned ),( karl ),( neal )) | |
| + | | | |
| + | | ( burglar , | |
| + | | ( al ),( jim ),( john ),( lance ), | |
| + | | ( george ),( don ),( ken ),( earl ),( rick )) | |
| + | | | |
| + | | ( pusher , | |
| + | | ( art ),( greg ),( fred ),( gene ), | |
| + | | ( ralph ),( phil ),( nick ),( ol ),( dave )) | |
| + | | | |
| + | o----------------------------------------------------------------o |
| + | |
| + | We now apply Study to the proposition that |
| + | defines the Jets and Sharks knowledge base, |
| + | that is to say, the knowledge that we are |
| + | given about the Jets and Sharks, not the |
| + | knowledge that the Jets and Sharks have. |
| + | |
| + | With a query on the name "ken" we obtain the following |
| + | output, giving all of the features associated with Ken: |
| + | |
| + | Sense Outline: JAS & Ken |
| + | o---------------------------------------o |
| + | | ken | |
| + | | sharks | |
| + | | 20's | |
| + | | high_school | |
| + | | single | |
| + | | burglar | |
| + | o---------------------------------------o |
| + | |
| + | With a query on the two features "college" and "sharks" |
| + | we obtain the following outline of all of the features |
| + | that satisfy these constraints: |
| + | |
| + | Sense Outline: JAS & College & Sharks |
| + | o---------------------------------------o |
| + | | college | |
| + | | sharks | |
| + | | 30's | |
| + | | married | |
| + | | bookie | |
| + | | ned | |
| + | | burglar | |
| + | | don | |
| + | | pusher | |
| + | | phil | |
| + | | ol | |
| + | o---------------------------------------o |
| + | |
| + | >From this we discover that all college Sharks |
| + | are 30-something and married. Furthermore, |
| + | we have a complete listing of their names |
| + | broken down by occupation, as I have no |
| + | doubt that all of them will be in time. |
| + | |
| + | | Reference: |
| + | | |
| + | | McClelland, James L. & Rumelhart, David E., |
| + | |'Explorations in Parallel Distributed Processing: |
| + | | A Handbook of Models, Programs, and Exercises', |
| + | | MIT Press, Cambridge, MA, 1988. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | One of the issues that my pondering weak and weary over |
| + | has caused me to burn not a few barrels of midnight oil |
| + | over the past elventeen years or so is the relationship |
| + | among divers and sundry "styles of inference", by which |
| + | I mean particular choices of inference paradigms, rules, |
| + | or schemata. The chief breakpoint seems to lie between |
| + | information-losing and information-maintaining modes of |
| + | inference, also called "implicational" and "equational", |
| + | or "projective" and "preservative" brands, respectively. |
| + | |
| + | Since it appears to be mostly the implicational and projective |
| + | styles of inference that are more familiar to folks hereabouts, |
| + | I will start off this subdiscussion by introducing a number of |
| + | risibly simple but reasonably manageable examples of the other |
| + | brand of inference, treated as equational reasoning approaches |
| + | to problems about satisfying "zeroth order constraints" (ZOC's). |
| + | |
| + | Applications of a Propositional Calculator: |
| + | Constraint Satisfaction Problems. |
| + | Jon Awbrey, April 24, 1995. |
| + | |
| + | The Four Houses Puzzle |
| + | |
| + | Constructed on the model of the "Five Houses Puzzle" in [VaH, 132-136]. |
| + | |
| + | Problem Statement. Four people with different nationalities live in the |
| + | first four houses of a street. They practice four distinct professions, |
| + | and each of them has a favorite animal, all of them different. The four |
| + | houses are painted different colors. The following facts are known: |
| + | |
| + | | 1. The Englander lives in the first house on the left. |
| + | | 2. The doctor lives in the second house. |
| + | | 3. The third house is painted red. |
| + | | 4. The zebra is a favorite in the fourth house. |
| + | | 5. The person in the first house has a dog. |
| + | | 6. The Japanese lives in the third house. |
| + | | 7. The red house is on the left of the yellow one. |
| + | | 8. They breed snails in the house to right of the doctor. |
| + | | 9. The Englander lives next to the green house. |
| + | | 10. The fox is in the house next to to the diplomat. |
| + | | 11. The Spaniard likes zebras. |
| + | | 12. The Japanese is a painter. |
| + | | 13. The Italian lives in the green house. |
| + | | 14. The violinist lives in the yellow house. |
| + | | 15. The dog is a pet in the blue house. |
| + | | 16. The doctor keeps a fox. |
| + | |
| + | The problem is to find all of the assignments of |
| + | features to houses that satisfy these requirements. |
| + | |
| + | Logical Input File: House^4.Log |
| + | o---------------------------------------------------------------------o |
| + | | | |
| + | | eng_1 doc_2 red_3 zeb_4 dog_1 jap_3 | |
| + | | | |
| + | | (( red_1 yel_2 ),( red_2 yel_3 ),( red_3 yel_4 )) | |
| + | | (( doc_1 sna_2 ),( doc_2 sna_3 ),( doc_3 sna_4 )) | |
| + | | | |
| + | | (( eng_1 gre_2 ), | |
| + | | ( eng_2 gre_3 ),( eng_2 gre_1 ), | |
| + | | ( eng_3 gre_4 ),( eng_3 gre_2 ), | |
| + | | ( eng_4 gre_3 )) | |
| + | | | |
| + | | (( dip_1 fox_2 ), | |
| + | | ( dip_2 fox_3 ),( dip_2 fox_1 ), | |
| + | | ( dip_3 fox_4 ),( dip_3 fox_2 ), | |
| + | | ( dip_4 fox_3 )) | |
| + | | | |
| + | | (( spa_1 zeb_1 ),( spa_2 zeb_2 ),( spa_3 zeb_3 ),( spa_4 zeb_4 )) | |
| + | | (( jap_1 pai_1 ),( jap_2 pai_2 ),( jap_3 pai_3 ),( jap_4 pai_4 )) | |
| + | | (( ita_1 gre_1 ),( ita_2 gre_2 ),( ita_3 gre_3 ),( ita_4 gre_4 )) | |
| + | | | |
| + | | (( yel_1 vio_1 ),( yel_2 vio_2 ),( yel_3 vio_3 ),( yel_4 vio_4 )) | |
| + | | (( blu_1 dog_1 ),( blu_2 dog_2 ),( blu_3 dog_3 ),( blu_4 dog_4 )) | |
| + | | | |
| + | | (( doc_1 fox_1 ),( doc_2 fox_2 ),( doc_3 fox_3 ),( doc_4 fox_4 )) | |
| + | | | |
| + | | (( | |
| + | | | |
| + | | (( eng_1 ),( eng_2 ),( eng_3 ),( eng_4 )) | |
| + | | (( spa_1 ),( spa_2 ),( spa_3 ),( spa_4 )) | |
| + | | (( jap_1 ),( jap_2 ),( jap_3 ),( jap_4 )) | |
| + | | (( ita_1 ),( ita_2 ),( ita_3 ),( ita_4 )) | |
| + | | | |
| + | | (( eng_1 ),( spa_1 ),( jap_1 ),( ita_1 )) | |
| + | | (( eng_2 ),( spa_2 ),( jap_2 ),( ita_2 )) | |
| + | | (( eng_3 ),( spa_3 ),( jap_3 ),( ita_3 )) | |
| + | | (( eng_4 ),( spa_4 ),( jap_4 ),( ita_4 )) | |
| + | | | |
| + | | (( gre_1 ),( gre_2 ),( gre_3 ),( gre_4 )) | |
| + | | (( red_1 ),( red_2 ),( red_3 ),( red_4 )) | |
| + | | (( yel_1 ),( yel_2 ),( yel_3 ),( yel_4 )) | |
| + | | (( blu_1 ),( blu_2 ),( blu_3 ),( blu_4 )) | |
| + | | | |
| + | | (( gre_1 ),( red_1 ),( yel_1 ),( blu_1 )) | |
| + | | (( gre_2 ),( red_2 ),( yel_2 ),( blu_2 )) | |
| + | | (( gre_3 ),( red_3 ),( yel_3 ),( blu_3 )) | |
| + | | (( gre_4 ),( red_4 ),( yel_4 ),( blu_4 )) | |
| + | | | |
| + | | (( pai_1 ),( pai_2 ),( pai_3 ),( pai_4 )) | |
| + | | (( dip_1 ),( dip_2 ),( dip_3 ),( dip_4 )) | |
| + | | (( vio_1 ),( vio_2 ),( vio_3 ),( vio_4 )) | |
| + | | (( doc_1 ),( doc_2 ),( doc_3 ),( doc_4 )) | |
| + | | | |
| + | | (( pai_1 ),( dip_1 ),( vio_1 ),( doc_1 )) | |
| + | | (( pai_2 ),( dip_2 ),( vio_2 ),( doc_2 )) | |
| + | | (( pai_3 ),( dip_3 ),( vio_3 ),( doc_3 )) | |
| + | | (( pai_4 ),( dip_4 ),( vio_4 ),( doc_4 )) | |
| + | | | |
| + | | (( dog_1 ),( dog_2 ),( dog_3 ),( dog_4 )) | |
| + | | (( zeb_1 ),( zeb_2 ),( zeb_3 ),( zeb_4 )) | |
| + | | (( fox_1 ),( fox_2 ),( fox_3 ),( fox_4 )) | |
| + | | (( sna_1 ),( sna_2 ),( sna_3 ),( sna_4 )) | |
| + | | | |
| + | | (( dog_1 ),( zeb_1 ),( fox_1 ),( sna_1 )) | |
| + | | (( dog_2 ),( zeb_2 ),( fox_2 ),( sna_2 )) | |
| + | | (( dog_3 ),( zeb_3 ),( fox_3 ),( sna_3 )) | |
| + | | (( dog_4 ),( zeb_4 ),( fox_4 ),( sna_4 )) | |
| + | | | |
| + | | )) | |
| + | | | |
| + | o---------------------------------------------------------------------o |
| + | |
| + | Sense Outline: House^4.Sen |
| + | o-----------------------------o |
| + | | eng_1 | |
| + | | doc_2 | |
| + | | red_3 | |
| + | | zeb_4 | |
| + | | dog_1 | |
| + | | jap_3 | |
| + | | yel_4 | |
| + | | sna_3 | |
| + | | gre_2 | |
| + | | dip_1 | |
| + | | fox_2 | |
| + | | spa_4 | |
| + | | pai_3 | |
| + | | ita_2 | |
| + | | vio_4 | |
| + | | blu_1 | |
| + | o-----------------------------o |
| + | |
| + | Table 1. Solution to the Four Houses Puzzle |
| + | o------------o------------o------------o------------o------------o |
| + | | | House 1 | House 2 | House 3 | House 4 | |
| + | o------------o------------o------------o------------o------------o |
| + | | Nation | England | Italy | Japan | Spain | |
| + | | Color | blue | green | red | yellow | |
| + | | Profession | diplomat | doctor | painter | violinist | |
| + | | Animal | dog | fox | snails | zebra | |
| + | o------------o------------o------------o------------o------------o |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | First off, I do not trivialize the "real issues of ontology", indeed, |
| + | it is precisely my estimate of the non-trivial difficulty of this task, |
| + | of formulating the types of "generic ontology" that we propose to do here, |
| + | that forces me to choose and to point out the inescapability of the approach |
| + | that I am currently taking, which is to enter on the necessary preliminary of |
| + | building up the logical tools that we need to tackle the ontology task proper. |
| + | And I would say, to the contrary, that it is those who think we can arrive at |
| + | a working general ontology by sitting on the porch shooting the breeze about |
| + | "what it is" until the cows come home -- that is, the method for which it |
| + | has become cliche to indict the Ancient Greeks, though, if truth be told, |
| + | we'd have to look to the pre-socratics and the pre-stoics to find a good |
| + | match for the kinds of revelation that are common hereabouts -- I would |
| + | say that it's those folks who trivialize the "real issues of ontology". |
| + | |
| + | A person, living in our times, who is serious about knowing the being of things, |
| + | really only has one choice -- to pick what tiny domain of things he or she just |
| + | has to know about the most, thence to hie away to the adept gurus of the matter |
| + | in question, forgeting the rest, cause "general ontology" is a no-go these days. |
| + | It is presently in a state like astronomy before telescopes, and that means not |
| + | entirely able to discern itself from astrology and other psychically projective |
| + | exercises of wishful and dreadful thinking like that. |
| + | |
| + | So I am busy grinding lenses ... |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | DM = Douglas McDavid |
| + | |
| + | DM: Thanks for both the original and additional response. I'm not trying to |
| + | single you out, as I have been picking on various postings in a similar |
| + | manner ever since I started contributing to this discussion. I agree with |
| + | you that the task of this working group is non-trivially difficult. In fact, |
| + | I believe we are still a long way from a clear and useful agreement about what |
| + | constitutes "upper" ontology, and what it would mean to standardize it. However, |
| + | I don't agree that the only place to make progress is in tiny domains of things. |
| + | I've contributed the thought that a fundamental, upper-level concept is the |
| + | concept of system, and that that would be a good place to begin. And I'll |
| + | never be able to refrain from evaluating the content as well as the form |
| + | of any examples presented for consideration here. Probably should |
| + | accompany these comments with a ;-) |
| + | |
| + | There will never be a standard universal ontology |
| + | of the absolute essential impertubable monolithic |
| + | variety that some people still dream of in their |
| + | fantasies of spectating on and speculating about |
| + | a pre-relativistically non-participatory universe |
| + | from their singular but isolated gods'eye'views. |
| + | The bells tolled for that one many years ago, |
| + | but some of the more blithe of the blissful |
| + | islanders have just not gotten the news yet. |
| + | |
| + | But there is still a lot to do that would be useful |
| + | under the banner of a "standard upper ontology", |
| + | if only we stay loose in our interpretation |
| + | of what that implies in practical terms. |
| + | |
| + | One likely approach to the problem would be to take |
| + | a hint from the afore-allusioned history of physics -- |
| + | to inquire for whom, else, the bell tolls -- and to |
| + | see if there are any bits of wisdom from that prior |
| + | round of collective experience that can be adapted |
| + | by dint of analogy to our present predicament. |
| + | I happen to think that there are. |
| + | |
| + | And there the answer was, not to try and force a return, |
| + | though lord knows they all gave it their very best shot, |
| + | to an absolute and imperturbable framework of existence, |
| + | but to see the reciprocal participant relation that all |
| + | partakers have to the constitution of that framing, yes, |
| + | even unto those who would abdictators and abstainees be. |
| + | |
| + | But what does that imply about some shred of a standard? |
| + | It means that we are better off seeking, not a standard, |
| + | one-size-fits-all ontology, but more standard resources |
| + | for trying to interrelate diverse points of view and to |
| + | transform the data that's gathered from one perspective |
| + | in ways that it can most appropriately be compared with |
| + | the data that is gathered from other standpoints on the |
| + | splendorous observational scenes and theorematic stages. |
| + | |
| + | That is what I am working on. |
| + | And it hasn't been merely |
| + | for a couple of years. |
| + | |
| + | As to this bit: |
| + | |
| + | o-------------------------------------------------o |
| + | | | |
| + | | ( living_thing , non_living ) | |
| + | | | |
| + | | (( animal ),( vegetable ),( mineral )) | |
| + | | | |
| + | | ( living_thing ,( animal ),( vegetable )) | |
| + | | | |
| + | | ( mineral ( non_living )) | |
| + | | | |
| + | o-------------------------------------------------o |
| + | |
| + | My 5-dimensional Example, that I borrowed from some indifferent source |
| + | of what is commonly recognized as "common sense" -- and I think rather |
| + | obviously designed more for the classification of pre-modern species |
| + | of whole critters and pure matters of natural substance than the |
| + | motley mixture of un/natural and in/organic conglouterites that |
| + | we find served up on the menu of modernity -- was not intended |
| + | even so much as a toy ontology, but simply as an expository |
| + | example, concocted for the sake of illustrating the sorts |
| + | of logical interaction that occur among four different |
| + | patterns of logical constraint, all of which types |
| + | arise all the time no matter what the domain, and |
| + | which I believe that my novel forms of expression, |
| + | syntactically speaking, express quite succinctly, |
| + | especially when you contemplate the complexities |
| + | of the computation that may flow and must follow |
| + | from even these meagre propositional expressions. |
| + | |
| + | Yes, systems -- but -- even here usage differs in significant ways. |
| + | I have spent ten years now trying to integrate my earlier efforts |
| + | under an explicit systems banner, but even within the bounds of |
| + | a systems engineering programme at one site there is a wide |
| + | semantic dispersion that issues from this word "system". |
| + | I am committed, and in writing, to taking what we so |
| + | glibly and prospectively call "intelligent systems" |
| + | seriously as dynamical systems. That has many |
| + | consequences, and I have to pick and choose |
| + | which of those I may be suited to follow. |
| + | |
| + | But that is too long a story for now ... |
| + | |
| + | ";-)"? |
| + | |
| + | Somehow that has always looked like |
| + | the Chesshire Cat's grin to me ... |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | By way of catering to popular demand, I have decided to |
| + | render this symposium a bit more à la carte, and thus to |
| + | serve up as faster food than heretofore a choice selection |
| + | of the more sumptuous bits that I have in my logical larder, |
| + | not yet full fare, by any means, but a sample of what might |
| + | one day approach to being an abundantly moveable feast of |
| + | ontological contents and general metaphysical delights. |
| + | I'll leave it to you to name your poison, as it were. |
| + | |
| + | Applications of a Propositional Calculator: |
| + | Constraint Satisfaction Problems. |
| + | Jon Awbrey, April 24, 1995. |
| + | |
| + | Fabric Knowledge Base |
| + | Based on the example in [MaW, pages 8-16]. |
| + | |
| + | Logical Input File: Fab.Log |
| + | o---------------------------------------------------------------------o |
| + | | | |
| + | | (has_floats , plain_weave ) | |
| + | | (has_floats ,(twill_weave ),(satin_weave )) | |
| + | | | |
| + | | (plain_weave , | |
| + | | (plain_weave one_color ), | |
| + | | (color_groups ), | |
| + | | (grouped_warps ), | |
| + | | (some_thicker ), | |
| + | | (crossed_warps ), | |
| + | | (loop_threads ), | |
| + | | (plain_weave flannel )) | |
| + | | | |
| + | | (plain_weave one_color cotton balanced smooth ,(percale )) | |
| + | | (plain_weave one_color cotton sheer ,(organdy )) | |
| + | | (plain_weave one_color silk sheer ,(organza )) | |
| + | | | |
| + | | (plain_weave color_groups warp_stripe fill_stripe ,(plaid )) | |
| + | | (plaid equal_stripe ,(gingham )) | |
| + | | | |
| + | | (plain_weave grouped_warps ,(basket_weave )) | |
| + | | | |
| + | | (basket_weave typed , | |
| + | | (type_2_to_1 ), | |
| + | | (type_2_to_2 ), | |
| + | | (type_4_to_4 )) | |
| + | | | |
| + | | (basket_weave typed type_2_to_1 thicker_fill ,(oxford )) | |
| + | | (basket_weave typed (type_2_to_2 , | |
| + | | type_4_to_4 ) same_thickness ,(monks_cloth )) | |
| + | | (basket_weave (typed ) rough open ,(hopsacking )) | |
| + | | | |
| + | | (typed (basket_weave )) | |
| + | | | |
| + | | (basket_weave ,(oxford ),(monks_cloth ),(hopsacking )) | |
| + | | | |
| + | | (plain_weave some_thicker ,(ribbed_weave )) | |
| + | | | |
| + | | (ribbed_weave ,(small_rib ),(medium_rib ),(heavy_rib )) | |
| + | | (ribbed_weave ,(flat_rib ),(round_rib )) | |
| + | | | |
| + | | (ribbed_weave thicker_fill ,(cross_ribbed )) | |
| + | | (cross_ribbed small_rib flat_rib ,(faille )) | |
| + | | (cross_ribbed small_rib round_rib ,(grosgrain )) | |
| + | | (cross_ribbed medium_rib round_rib ,(bengaline )) | |
| + | | (cross_ribbed heavy_rib round_rib ,(ottoman )) | |
| + | | | |
| + | | (cross_ribbed ,(faille ),(grosgrain ),(bengaline ),(ottoman )) | |
| + | | | |
| + | | (plain_weave crossed_warps ,(leno_weave )) | |
| + | | (leno_weave open ,(marquisette )) | |
| + | | (plain_weave loop_threads ,(pile_weave )) | |
| + | | | |
| + | | (pile_weave ,(fill_pile ),(warp_pile )) | |
| + | | (pile_weave ,(cut ),(uncut )) | |
| + | | | |
| + | | (pile_weave warp_pile cut ,(velvet )) | |
| + | | (pile_weave fill_pile cut aligned_pile ,(corduroy )) | |
| + | | (pile_weave fill_pile cut staggered_pile ,(velveteen )) | |
| + | | (pile_weave fill_pile uncut reversible ,(terry )) | |
| + | | | |
| + | | (pile_weave fill_pile cut ( (aligned_pile , staggered_pile ) )) | |
| + | | | |
| + | | (pile_weave ,(velvet ),(corduroy ),(velveteen ),(terry )) | |
| + | | | |
| + | | (plain_weave , | |
| + | | (percale ),(organdy ),(organza ),(plaid ), | |
| + | | (oxford ),(monks_cloth ),(hopsacking ), | |
| + | | (faille ),(grosgrain ),(bengaline ),(ottoman ), | |
| + | | (leno_weave ),(pile_weave ),(plain_weave flannel )) | |
| + | | | |
| + | | (twill_weave , | |
| + | | (warp_faced ), | |
| + | | (filling_faced ), | |
| + | | (even_twill ), | |
| + | | (twill_weave flannel )) | |
| + | | | |
| + | | (twill_weave warp_faced colored_warp white_fill ,(denim )) | |
| + | | (twill_weave warp_faced one_color ,(drill )) | |
| + | | (twill_weave even_twill diagonal_rib ,(serge )) | |
| + | | | |
| + | | (twill_weave warp_faced ( | |
| + | | (one_color , | |
| + | | ((colored_warp )(white_fill )) ) | |
| + | | )) | |
| + | | | |
| + | | (twill_weave warp_faced ,(denim ),(drill )) | |
| + | | (twill_weave even_twill ,(serge )) | |
| + | | | |
| + | | (( | |
| + | | ( ((plain_weave )(twill_weave )) | |
| + | | ((cotton )(wool )) napped ,(flannel )) | |
| + | | )) | |
| + | | | |
| + | | (satin_weave ,(warp_floats ),(fill_floats )) | |
| + | | | |
| + | | (satin_weave ,(satin_weave smooth ),(satin_weave napped )) | |
| + | | (satin_weave ,(satin_weave cotton ),(satin_weave silk )) | |
| + | | | |
| + | | (satin_weave warp_floats smooth ,(satin )) | |
| + | | (satin_weave fill_floats smooth ,(sateen )) | |
| + | | (satin_weave napped cotton ,(moleskin )) | |
| + | | | |
| + | | (satin_weave ,(satin ),(sateen ),(moleskin )) | |
| + | | | |
| + | o---------------------------------------------------------------------o |
| + | |
| + | | Reference [MaW] |
| + | | |
| + | | Maier, David & Warren, David S., |
| + | |'Computing with Logic: Logic Programming with Prolog', |
| + | | Benjamin/Cummings, Menlo Park, CA, 1988. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | I think that it might be a good idea to go back to a simpler example |
| + | of a constraint satisfaction problem, and to discuss the elements of |
| + | its expression as a ZOT in a less cluttered setting before advancing |
| + | onward once again to problems on the order of the Four Houses Puzzle. |
| + | |
| + | | Applications of a Propositional Calculator: |
| + | | Constraint Satisfaction Problems. |
| + | | Jon Awbrey, April 24, 1995. |
| + | |
| + | Graph Coloring |
| + | |
| + | Based on the discussion in [Wil, page 196]. |
| + | |
| + | One is given three colors, say, orange, silver, indigo, |
| + | and a graph on four nodes that has the following shape: |
| + | |
| + | | 1 |
| + | | o |
| + | | / \ |
| + | | / \ |
| + | | 4 o-----o 2 |
| + | | \ / |
| + | | \ / |
| + | | o |
| + | | 3 |
| + | |
| + | The problem is to color the nodes of the graph |
| + | in such a way that no pair of nodes that are |
| + | adjacent in the graph, that is, linked by |
| + | an edge, get the same color. |
| + | |
| + | The objective situation that is to be achieved can be represented |
| + | in a so-called "declarative" fashion, in effect, by employing the |
| + | cactus language as a very simple sort of declarative programming |
| + | language, and depicting the prospective solution to the problem |
| + | as a ZOT. |
| + | |
| + | To do this, begin by declaring the following set of |
| + | twelve boolean variables or "zeroth order features": |
| + | |
| + | {1_orange, 1_silver, 1_indigo, |
| + | 2_orange, 2_silver, 2_indigo, |
| + | 3_orange, 3_silver, 3_indigo, |
| + | 4_orange, 4_silver, 4_indigo} |
| + | |
| + | The interpretation to keep in mind will be such that |
| + | the feature name of the form "<node i>_<color j>" |
| + | says that the node i is assigned the color j. |
| + | |
| + | Logical Input File: Color.Log |
| + | o----------------------------------------------------------------------o |
| + | | | |
| + | | (( 1_orange ),( 1_silver ),( 1_indigo )) | |
| + | | (( 2_orange ),( 2_silver ),( 2_indigo )) | |
| + | | (( 3_orange ),( 3_silver ),( 3_indigo )) | |
| + | | (( 4_orange ),( 4_silver ),( 4_indigo )) | |
| + | | | |
| + | | ( 1_orange 2_orange )( 1_silver 2_silver )( 1_indigo 2_indigo ) | |
| + | | ( 1_orange 4_orange )( 1_silver 4_silver )( 1_indigo 4_indigo ) | |
| + | | ( 2_orange 3_orange )( 2_silver 3_silver )( 2_indigo 3_indigo ) | |
| + | | ( 2_orange 4_orange )( 2_silver 4_silver )( 2_indigo 4_indigo ) | |
| + | | ( 3_orange 4_orange )( 3_silver 4_silver )( 3_indigo 4_indigo ) | |
| + | | | |
| + | o----------------------------------------------------------------------o |
| + | |
| + | The first stanza of verses declares that |
| + | every node is assigned exactly one color. |
| + | |
| + | The second stanza of verses declares that |
| + | no adjacent nodes get the very same color. |
| + | |
| + | Each satisfying interpretation of this ZOT |
| + | that is also a program corresponds to what |
| + | graffitists call a "coloring" of the graph. |
| + | |
| + | Theme One's Model interpreter, when we set |
| + | it to work on this ZOT, will array before |
| + | our eyes all of the colorings of the graph. |
| + | |
| + | Sense Outline: Color.Sen |
| + | o-----------------------------o |
| + | | 1_orange | |
| + | | 2_silver | |
| + | | 3_orange | |
| + | | 4_indigo | |
| + | | 2_indigo | |
| + | | 3_orange | |
| + | | 4_silver | |
| + | | 1_silver | |
| + | | 2_orange | |
| + | | 3_silver | |
| + | | 4_indigo | |
| + | | 2_indigo | |
| + | | 3_silver | |
| + | | 4_orange | |
| + | | 1_indigo | |
| + | | 2_orange | |
| + | | 3_indigo | |
| + | | 4_silver | |
| + | | 2_silver | |
| + | | 3_indigo | |
| + | | 4_orange | |
| + | o-----------------------------o |
| + | |
| + | | Reference [Wil] |
| + | | |
| + | | Wilf, Herbert S., |
| + | |'Algorithms and Complexity', |
| + | | Prentice-Hall, Englewood Cliffs, NJ, 1986. |
| + | | |
| + | | Nota Bene. There is a wrong Figure in some |
| + | | printings of the book, that does not match |
| + | | the description of the Example that is |
| + | | given in the text. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Let us continue to examine the properties of the cactus language |
| + | as a minimal style of declarative programming language. Even in |
| + | the likes of this zeroth order microcosm one can observe, and on |
| + | a good day still more clearly for the lack of other distractions, |
| + | many of the buzz worlds that will spring into full bloom, almost |
| + | as if from nowhere, to become the first order of business in the |
| + | latter day logical organa, plus combinators, plus lambda calculi. |
| + | |
| + | By way of homage to the classics of the art, I can hardly pass |
| + | this way without paying my dues to the next sample of examples. |
| + | |
| + | N Queens Problem |
| + | |
| + | I will give the ZOT that describes the N Queens Problem for N = 5, |
| + | since that is the most that I and my old 286 could do when last I |
| + | wrote up this Example. |
| + | |
| + | The problem is now to write a "zeroth order program" (ZOP) that |
| + | describes the following objective: To place 5 chess queens on |
| + | a 5 by 5 chessboard so that no queen attacks any other queen. |
| + | |
| + | It is clear that there can be at most one queen on each row |
| + | of the board and so by dint of regal necessity, exactly one |
| + | queen in each row of the desired array. This gambit allows |
| + | us to reduce the problem to one of picking a permutation of |
| + | five things in fives places, and this affords us sufficient |
| + | clue to begin down a likely path toward the intended object, |
| + | by recruiting the following phalanx of 25 logical variables: |
| + | |
| + | Literal Input File: Q5.Lit |
| + | o---------------------------------------o |
| + | | | |
| + | | q1_r1, q1_r2, q1_r3, q1_r4, q1_r5, | |
| + | | q2_r1, q2_r2, q2_r3, q2_r4, q2_r5, | |
| + | | q3_r1, q3_r2, q3_r3, q3_r4, q3_r5, | |
| + | | q4_r1, q4_r2, q4_r3, q4_r4, q4_r5, | |
| + | | q5_r1, q5_r2, q5_r3, q5_r4, q5_r5. | |
| + | | | |
| + | o---------------------------------------o |
| + | |
| + | Thus we seek to define a function, of abstract type f : %B%^25 -> %B%, |
| + | whose fibre of truth f^(-1)(%1%) is a set of interpretations, each of |
| + | whose elements bears the abstract type of a point in the space %B%^25, |
| + | and whose reading will inform us of our desired set of configurations. |
| + | |
| + | Logical Input File: Q5.Log |
| + | o------------------------------------------------------------o |
| + | | | |
| + | | ((q1_r1 ),(q1_r2 ),(q1_r3 ),(q1_r4 ),(q1_r5 )) | |
| + | | ((q2_r1 ),(q2_r2 ),(q2_r3 ),(q2_r4 ),(q2_r5 )) | |
| + | | ((q3_r1 ),(q3_r2 ),(q3_r3 ),(q3_r4 ),(q3_r5 )) | |
| + | | ((q4_r1 ),(q4_r2 ),(q4_r3 ),(q4_r4 ),(q4_r5 )) | |
| + | | ((q5_r1 ),(q5_r2 ),(q5_r3 ),(q5_r4 ),(q5_r5 )) | |
| + | | | |
| + | | ((q1_r1 ),(q2_r1 ),(q3_r1 ),(q4_r1 ),(q5_r1 )) | |
| + | | ((q1_r2 ),(q2_r2 ),(q3_r2 ),(q4_r2 ),(q5_r2 )) | |
| + | | ((q1_r3 ),(q2_r3 ),(q3_r3 ),(q4_r3 ),(q5_r3 )) | |
| + | | ((q1_r4 ),(q2_r4 ),(q3_r4 ),(q4_r4 ),(q5_r4 )) | |
| + | | ((q1_r5 ),(q2_r5 ),(q3_r5 ),(q4_r5 ),(q5_r5 )) | |
| + | | | |
| + | | (( | |
| + | | | |
| + | | (q1_r1 q2_r2 )(q1_r1 q3_r3 )(q1_r1 q4_r4 )(q1_r1 q5_r5 ) | |
| + | | (q2_r2 q3_r3 )(q2_r2 q4_r4 )(q2_r2 q5_r5 ) | |
| + | | (q3_r3 q4_r4 )(q3_r3 q5_r5 ) | |
| + | | (q4_r4 q5_r5 ) | |
| + | | | |
| + | | (q1_r2 q2_r3 )(q1_r2 q3_r4 )(q1_r2 q4_r5 ) | |
| + | | (q2_r3 q3_r4 )(q2_r3 q4_r5 ) | |
| + | | (q3_r4 q4_r5 ) | |
| + | | | |
| + | | (q1_r3 q2_r4 )(q1_r3 q3_r5 ) | |
| + | | (q2_r4 q3_r5 ) | |
| + | | | |
| + | | (q1_r4 q2_r5 ) | |
| + | | | |
| + | | (q2_r1 q3_r2 )(q2_r1 q4_r3 )(q2_r1 q5_r4 ) | |
| + | | (q3_r2 q4_r3 )(q3_r2 q5_r4 ) | |
| + | | (q4_r3 q5_r4 ) | |
| + | | | |
| + | | (q3_r1 q4_r2 )(q3_r1 q5_r3 ) | |
| + | | (q4_r2 q5_r3 ) | |
| + | | | |
| + | | (q4_r1 q5_r2 ) | |
| + | | | |
| + | | (q1_r5 q2_r4 )(q1_r5 q3_r3 )(q1_r5 q4_r2 )(q1_r5 q5_r1 ) | |
| + | | (q2_r4 q3_r3 )(q2_r4 q4_r2 )(q2_r4 q5_r1 ) | |
| + | | (q3_r3 q4_r2 )(q3_r3 q5_r1 ) | |
| + | | (q4_r2 q5_r1 ) | |
| + | | | |
| + | | (q2_r5 q3_r4 )(q2_r5 q4_r3 )(q2_r5 q5_r2 ) | |
| + | | (q3_r4 q4_r3 )(q3_r4 q5_r2 ) | |
| + | | (q4_r3 q5_r2 ) | |
| + | | | |
| + | | (q3_r5 q4_r4 )(q3_r5 q5_r3 ) | |
| + | | (q4_r4 q5_r3 ) | |
| + | | | |
| + | | (q4_r5 q5_r4 ) | |
| + | | | |
| + | | (q1_r4 q2_r3 )(q1_r4 q3_r2 )(q1_r4 q4_r1 ) | |
| + | | (q2_r3 q3_r2 )(q2_r3 q4_r1 ) | |
| + | | (q3_r2 q4_r1 ) | |
| + | | | |
| + | | (q1_r3 q2_r2 )(q1_r3 q3_r1 ) | |
| + | | (q2_r2 q3_r1 ) | |
| + | | | |
| + | | (q1_r2 q2_r1 ) | |
| + | | | |
| + | | )) | |
| + | | | |
| + | o------------------------------------------------------------o |
| + | |
| + | The vanguard of this logical regiment consists of two |
| + | stock'a'block platoons, the pattern of whose features |
| + | is the usual sort of array for conveying permutations. |
| + | Between the stations of their respective offices they |
| + | serve to warrant that all of the interpretations that |
| + | are left standing on the field of valor at the end of |
| + | the day will be ones that tell of permutations 5 by 5. |
| + | The rest of the ruck and the runt of the mill in this |
| + | regimental logos are there to cover the diagonal bias |
| + | against attacking queens that is our protocol to suit. |
| + | |
| + | And here is the issue of the day: |
| + | |
| + | Sense Output: Q5.Sen |
| + | o-------------------o |
| + | | q1_r1 | |
| + | | q2_r3 | |
| + | | q3_r5 | |
| + | | q4_r2 | |
| + | | q5_r4 | <1> |
| + | | q2_r4 | |
| + | | q3_r2 | |
| + | | q4_r5 | |
| + | | q5_r3 | <2> |
| + | | q1_r2 | |
| + | | q2_r4 | |
| + | | q3_r1 | |
| + | | q4_r3 | |
| + | | q5_r5 | <3> |
| + | | q2_r5 | |
| + | | q3_r3 | |
| + | | q4_r1 | |
| + | | q5_r4 | <4> |
| + | | q1_r3 | |
| + | | q2_r1 | |
| + | | q3_r4 | |
| + | | q4_r2 | |
| + | | q5_r5 | <5> |
| + | | q2_r5 | |
| + | | q3_r2 | |
| + | | q4_r4 | |
| + | | q5_r1 | <6> |
| + | | q1_r4 | |
| + | | q2_r1 | |
| + | | q3_r3 | |
| + | | q4_r5 | |
| + | | q5_r2 | <7> |
| + | | q2_r2 | |
| + | | q3_r5 | |
| + | | q4_r3 | |
| + | | q5_r1 | <8> |
| + | | q1_r5 | |
| + | | q2_r2 | |
| + | | q3_r4 | |
| + | | q4_r1 | |
| + | | q5_r3 | <9> |
| + | | q2_r3 | |
| + | | q3_r1 | |
| + | | q4_r4 | |
| + | | q5_r2 | <A> |
| + | o-------------------o |
| + | |
| + | The number at least checks with all of the best authorities, |
| + | so I can breathe a sigh of relief on that account, at least. |
| + | I am sure that there just has to be a more clever way to do |
| + | this, that is to say, within the bounds of ZOT reason alone, |
| + | but the above is the best that I could figure out with the |
| + | time that I had at the time. |
| + | |
| + | References: [BaC, 166], [VaH, 122], [Wir, 143]. |
| + | |
| + | [BaC] Ball, W.W. Rouse, & Coxeter, H.S.M., |
| + | 'Mathematical Recreations and Essays', |
| + | 13th ed., Dover, New York, NY, 1987. |
| + | |
| + | [VaH] Van Hentenryck, Pascal, |
| + | 'Constraint Satisfaction in Logic Programming, |
| + | MIT Press, Cambridge, MA, 1989. |
| + | |
| + | [Wir] Wirth, Niklaus, |
| + | 'Algorithms + Data Structures = Programs', |
| + | Prentice-Hall, Englewood Cliffs, NJ, 1976. |
| + | |
| + | http://mathworld.wolfram.com/QueensProblem.html |
| + | http://www.research.att.com/cgi-bin/access.cgi/as/njas/sequences/eisA.cgi?Anum=000170 |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | I turn now to another golden oldie of a constraint satisfaction problem |
| + | that I would like to give here a slightly new spin, but not so much for |
| + | the sake of these trifling novelties as from a sense of old time's ache |
| + | and a duty to -- well, what's the opposite of novelty? |
| + | |
| + | Phobic Apollo |
| + | |
| + | | Suppose Peter, Paul, and Jane are musicians. One of them plays |
| + | | saxophone, another plays guitar, and the third plays drums. As |
| + | | it happens, one of them is afraid of things associated with the |
| + | | number 13, another of them is afraid of cats, and the third is |
| + | | afraid of heights. You also know that Peter and the guitarist |
| + | | skydive, that Paul and the saxophone player enjoy cats, and |
| + | | that the drummer lives in apartment 13 on the 13th floor. |
| + | | |
| + | | Soon we will want to use these facts to reason |
| + | | about whether or not certain identity relations |
| + | | hold or are excluded. Assume X(Peter, Guitarist) |
| + | | means "the person who is Peter is not the person who |
| + | | plays the guitar". In this notation, the facts become: |
| + | | |
| + | | 1. X(Peter, Guitarist) |
| + | | 2. X(Peter, Fears Heights) |
| + | | 3. X(Guitarist, Fears Heights) |
| + | | 4. X(Paul, Fears Cats) |
| + | | 5. X(Paul, Saxophonist) |
| + | | 6. X(Saxophonist, Fears Cats) |
| + | | 7. X(Drummer, Fears 13) |
| + | | 8. X(Drummer, Fears Heights) |
| + | | |
| + | | Exercise attributed to Kenneth D. Forbus, pages 449-450 in: |
| + | | Patrick Henry Winston, 'Artificial Intelligence', 2nd ed., |
| + | | Addison-Wesley, Reading, MA, 1984. |
| + | |
| + | Here is one way to represent these facts in the form of a ZOT |
| + | and use it as a logical program to draw a succinct conclusion: |
| + | |
| + | Logical Input File: ConSat.Log |
| + | o-----------------------------------------------------------------------o |
| + | | | |
| + | | (( pete_plays_guitar ),( pete_plays_sax ),( pete_plays_drums )) | |
| + | | (( paul_plays_guitar ),( paul_plays_sax ),( paul_plays_drums )) | |
| + | | (( jane_plays_guitar ),( jane_plays_sax ),( jane_plays_drums )) | |
| + | | | |
| + | | (( pete_plays_guitar ),( paul_plays_guitar ),( jane_plays_guitar )) | |
| + | | (( pete_plays_sax ),( paul_plays_sax ),( jane_plays_sax )) | |
| + | | (( pete_plays_drums ),( paul_plays_drums ),( jane_plays_drums )) | |
| + | | | |
| + | | (( pete_fears_13 ),( pete_fears_cats ),( pete_fears_height )) | |
| + | | (( paul_fears_13 ),( paul_fears_cats ),( paul_fears_height )) | |
| + | | (( jane_fears_13 ),( jane_fears_cats ),( jane_fears_height )) | |
| + | | | |
| + | | (( pete_fears_13 ),( paul_fears_13 ),( jane_fears_13 )) | |
| + | | (( pete_fears_cats ),( paul_fears_cats ),( jane_fears_cats )) | |
| + | | (( pete_fears_height ),( paul_fears_height ),( jane_fears_height )) | |
| + | | | |
| + | | (( | |
| + | | | |
| + | | ( pete_plays_guitar ) | |
| + | | ( pete_fears_height ) | |
| + | | | |
| + | | ( pete_plays_guitar pete_fears_height ) | |
| + | | ( paul_plays_guitar paul_fears_height ) | |
| + | | ( jane_plays_guitar jane_fears_height ) | |
| + | | | |
| + | | ( paul_fears_cats ) | |
| + | | ( paul_plays_sax ) | |
| + | | | |
| + | | ( pete_plays_sax pete_fears_cats ) | |
| + | | ( paul_plays_sax paul_fears_cats ) | |
| + | | ( jane_plays_sax jane_fears_cats ) | |
| + | | | |
| + | | ( pete_plays_drums pete_fears_13 ) | |
| + | | ( paul_plays_drums paul_fears_13 ) | |
| + | | ( jane_plays_drums jane_fears_13 ) | |
| + | | | |
| + | | ( pete_plays_drums pete_fears_height ) | |
| + | | ( paul_plays_drums paul_fears_height ) | |
| + | | ( jane_plays_drums jane_fears_height ) | |
| + | | | |
| + | | )) | |
| + | | | |
| + | o-----------------------------------------------------------------------o |
| + | |
| + | Sense Outline: ConSat.Sen |
| + | o-----------------------------o |
| + | | pete_plays_drums | |
| + | | paul_plays_guitar | |
| + | | jane_plays_sax | |
| + | | pete_fears_cats | |
| + | | paul_fears_13 | |
| + | | jane_fears_height | |
| + | o-----------------------------o |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Phobic Apollo (cont.) |
| + | |
| + | It might be instructive to review various aspects |
| + | of how the Theme One Study function actually went |
| + | about arriving at its answer to that last problem. |
| + | Just to prove that my program and I really did do |
| + | our homework on that Phobic Apollo ConSat problem, |
| + | and didn't just provoke some Oracle or other data |
| + | base server to give it away, here is the middling |
| + | output of the Model function as run on ConSat.Log: |
| + | |
| + | Model Outline: ConSat.Mod |
| + | o-------------------------------------------------o |
| + | | pete_plays_guitar - | |
| + | | (pete_plays_guitar ) | |
| + | | pete_plays_sax | |
| + | | pete_plays_drums - | |
| + | | (pete_plays_drums ) | |
| + | | paul_plays_sax - | |
| + | | (paul_plays_sax ) | |
| + | | jane_plays_sax - | |
| + | | (jane_plays_sax ) | |
| + | | paul_plays_guitar | |
| + | | paul_plays_drums - | |
| + | | (paul_plays_drums ) | |
| + | | jane_plays_guitar - | |
| + | | (jane_plays_guitar ) | |
| + | | jane_plays_drums | |
| + | | pete_fears_13 | |
| + | | pete_fears_cats - | |
| + | | (pete_fears_cats ) | |
| + | | pete_fears_height - | |
| + | | (pete_fears_height ) | |
| + | | paul_fears_13 - | |
| + | | (paul_fears_13 ) | |
| + | | jane_fears_13 - | |
| + | | (jane_fears_13 ) | |
| + | | paul_fears_cats - | |
| + | | (paul_fears_cats ) | |
| + | | paul_fears_height - | |
| + | | (paul_fears_height ) - | |
| + | | (pete_fears_13 ) | |
| + | | pete_fears_cats - | |
| + | | (pete_fears_cats ) | |
| + | | pete_fears_height - | |
| + | | (pete_fears_height ) - | |
| + | | (jane_plays_drums ) - | |
| + | | (paul_plays_guitar ) | |
| + | | paul_plays_drums | |
| + | | jane_plays_drums - | |
| + | | (jane_plays_drums ) | |
| + | | jane_plays_guitar | |
| + | | pete_fears_13 | |
| + | | pete_fears_cats - | |
| + | | (pete_fears_cats ) | |
| + | | pete_fears_height - | |
| + | | (pete_fears_height ) | |
| + | | paul_fears_13 - | |
| + | | (paul_fears_13 ) | |
| + | | jane_fears_13 - | |
| + | | (jane_fears_13 ) | |
| + | | paul_fears_cats - | |
| + | | (paul_fears_cats ) | |
| + | | paul_fears_height - | |
| + | | (paul_fears_height ) - | |
| + | | (pete_fears_13 ) | |
| + | | pete_fears_cats - | |
| + | | (pete_fears_cats ) | |
| + | | pete_fears_height - | |
| + | | (pete_fears_height ) - | |
| + | | (jane_plays_guitar ) - | |
| + | | (paul_plays_drums ) - | |
| + | | (pete_plays_sax ) | |
| + | | pete_plays_drums | |
| + | | paul_plays_drums - | |
| + | | (paul_plays_drums ) | |
| + | | jane_plays_drums - | |
| + | | (jane_plays_drums ) | |
| + | | paul_plays_guitar | |
| + | | paul_plays_sax - | |
| + | | (paul_plays_sax ) | |
| + | | jane_plays_guitar - | |
| + | | (jane_plays_guitar ) | |
| + | | jane_plays_sax | |
| + | | pete_fears_13 - | |
| + | | (pete_fears_13 ) | |
| + | | pete_fears_cats | |
| + | | pete_fears_height - | |
| + | | (pete_fears_height ) | |
| + | | paul_fears_cats - | |
| + | | (paul_fears_cats ) | |
| + | | jane_fears_cats - | |
| + | | (jane_fears_cats ) | |
| + | | paul_fears_13 | |
| + | | paul_fears_height - | |
| + | | (paul_fears_height ) | |
| + | | jane_fears_13 - | |
| + | | (jane_fears_13 ) | |
| + | | jane_fears_height * | |
| + | | (jane_fears_height ) - | |
| + | | (paul_fears_13 ) | |
| + | | paul_fears_height - | |
| + | | (paul_fears_height ) - | |
| + | | (pete_fears_cats ) | |
| + | | pete_fears_height - | |
| + | | (pete_fears_height ) - | |
| + | | (jane_plays_sax ) - | |
| + | | (paul_plays_guitar ) | |
| + | | paul_plays_sax - | |
| + | | (paul_plays_sax ) - | |
| + | | (pete_plays_drums ) - | |
| + | o-------------------------------------------------o |
| + | |
| + | This is just the traverse of the "arboreal boolean expansion" (ABE) tree |
| + | that Model function germinates from the propositional expression that we |
| + | planted in the file Consat.Log, which works to describe the facts of the |
| + | situation in question. Since there are 18 logical feature names in this |
| + | propositional expression, we are literally talking about a function that |
| + | enjoys the abstract type f : %B%^18 -> %B%. If I had wanted to evaluate |
| + | this function by expressly writing out its truth table, then it would've |
| + | required 2^18 = 262144 rows. Now I didn't bother to count, but I'm sure |
| + | that the above output does not have anywhere near that many lines, so it |
| + | must be that my program, and maybe even its author, has done a couple of |
| + | things along the way that are moderately intelligent. At least, we hope. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | AK = Antti Karttunen |
| + | JA = Jon Awbrey |
| + | |
| + | AK: Am I (and other SeqFanaticians) missing something from this thread? |
| + | |
| + | AK: Your previous message on seqfan (headers below) is a bit of the same topic, |
| + | but does it belong to the same thread? Where I could obtain the other |
| + | messages belonging to those two threads? (I'm just now starting to |
| + | study "mathematical logic", and its relations to combinatorics are |
| + | very interesting.) Is this "cactus" language documented anywhere? |
| + | |
| + | here i was just following a courtesy of copying people |
| + | when i reference their works, in this case neil's site: |
| + | |
| + | http://www.research.att.com/cgi-bin/access.cgi/as/njas/sequences/eisA.cgi?Anum=000170 |
| + | |
| + | but then i thought that the seqfantasians might be amused, too. |
| + | |
| + | the bit on higher order propositions, in particular, |
| + | those of type h : (B^2 -> B) -> B, i sent because |
| + | of the significance that 2^2^2^2 = 65536 took on |
| + | for us around that time. & the ho, ho, ho joke. |
| + | |
| + | "zeroth order logic" (zol) is just another name for |
| + | the propositional calculus or the sentential logic |
| + | that comes before "first order logic" (fol), aka |
| + | first intens/tional logic, quantificational logic, |
| + | or predicate calculus, depending on who you talk to. |
| + | |
| + | the line of work that i have been doing derives from |
| + | the ideas of c.s. peirce (1839-1914), who developed |
| + | a couple of systems of "logical graphs", actually, |
| + | two variant interpretations of the same abstract |
| + | structures, called "entitative" and "existential" |
| + | graphs. he organized his system into "alpha", |
| + | "beta", and "gamma" layers, roughly equivalent |
| + | to our propositional, quantificational, and |
| + | modal levels of logic today. |
| + | |
| + | on the more contemporary scene, peirce's entitative interpretation |
| + | of logical graphs was revived and extended by george spencer brown |
| + | in his book 'laws of form', while the existential interpretation |
| + | has flourished in the development of "conceptual graphs" by |
| + | john f sowa and a community of growing multitudes. |
| + | |
| + | a passel of links: |
| + | |
| + | http://members.door.net/arisbe/ |
| + | http://www.enolagaia.com/GSB.html |
| + | http://www.cs.uah.edu/~delugach/CG/ |
| + | http://www.jfsowa.com/ |
| + | http://www.jfsowa.com/cg/ |
| + | http://www.jfsowa.com/peirce/ms514w.htm |
| + | http://users.bestweb.net/~sowa/ |
| + | http://users.bestweb.net/~sowa/peirce/ms514.htm |
| + | |
| + | i have mostly focused on "alpha" (prop calc or zol) -- |
| + | though the "func conception of quant logic" thread was |
| + | a beginning try at saying how the same line of thought |
| + | might be extended to 1st, 2nd, & higher order logics -- |
| + | and i devised a particular graph & string syntax that |
| + | is based on a species of cacti, officially described as |
| + | the "reflective extension of logical graphs" (ref log), |
| + | but more lately just referred to as "cactus language". |
| + | |
| + | it turns out that one can do many interesting things |
| + | with prop calc if one has an efficient enough syntax |
| + | and a powerful enough interpreter for it, even using |
| + | it as a very minimal sort of declarative programming |
| + | language, hence, the current thread was directed to |
| + | applying "zeroth order theories" (zot's) as brands |
| + | of "zeroth order programs" (zop's) to a set of old |
| + | constraint satisfaction and knowledge rep examples. |
| + | |
| + | more recent expositions of the cactus language have been directed |
| + | toward what some people call "ontology engineering" -- it sounds |
| + | so much cooler than "taxonomy" -- and so these are found in the |
| + | ieee standard upper ontology working group discussion archives. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Let's now pause and reflect on the mix of abstract and concrete material |
| + | that we have cobbled together in spectacle of this "World Of Zero" (WOZ), |
| + | since I believe that we may have seen enough, if we look at it right, to |
| + | illustrate a few of the more salient phenomena that would normally begin |
| + | to weigh in as a major force only on a much larger scale. Now, it's not |
| + | exactly like this impoverished sample, all by itself, could determine us |
| + | to draw just the right generalizations, or force us to see the shape and |
| + | flow of its immanent law -- it is much too sparse a scattering of points |
| + | to tease out the lines of its up and coming generations quite so clearly -- |
| + | but it can be seen to exemplify many of the more significant themes that |
| + | we know evolve in more substantial environments, that is, On Beyond Zero, |
| + | since we have already seen them, "tho' obscur'd", in these higher realms. |
| + | |
| + | One the the themes that I want to to keep an eye on as this discussion |
| + | develops is the subject that might be called "computation as semiosis". |
| + | |
| + | In this light, any calculus worth its salt must be capable of helping |
| + | us do two things, calculation, of course, but also analysis. This is |
| + | probably one of the reasons why the ordinary sort of differential and |
| + | integral calculus over quantitative domains is frequently referred to |
| + | as "real analysis", or even just "analysis". It seems quite clear to |
| + | me that any adequate logical calculus, in many ways expected to serve |
| + | as a qualitative analogue of analytic geometry in the way that it can |
| + | be used to describe configurations in logically circumscribed domains, |
| + | ought to qualify in both dimensions, namely, analysis and computation. |
| + | |
| + | With all of these various features of the situation in mind, then, we come |
| + | to the point of viewing analysis and computation as just so many different |
| + | kinds of "sign transformations in respect of pragmata" (STIROP's). Taking |
| + | this insight to heart, let us next work to assemble a comprehension of our |
| + | concrete examples, set in the medium of the abstract calculi that allow us |
| + | to express their qualitative patterns, that may hope to be an increment or |
| + | two less inchoate than we have seen so far, and that may even permit us to |
| + | catch the action of these fading fleeting sign transformations on the wing. |
| + | |
| + | Here is how I picture our latest round of examples |
| + | as filling out the framework of this investigation: |
| + | |
| + | o-----------------------------o-----------------------------o |
| + | | Objective Framework | Interpretive Framework | |
| + | o-----------------------------o-----------------------------o |
| + | | | |
| + | | s_1 = Logue(o) | | |
| + | | / | | |
| + | | / | | |
| + | | @ | | |
| + | | · \ | | |
| + | | · \ | | |
| + | | · i_1 = Model(o) v | |
| + | | · s_2 = Model(o) | | |
| + | | · / | | |
| + | | · / | | |
| + | | Object = o · · · · · · @ | | |
| + | | · \ | | |
| + | | · \ | | |
| + | | · i_2 = Tenor(o) v | |
| + | | · s_3 = Tenor(o) | | |
| + | | · / | | |
| + | | · / | | |
| + | | @ | | |
| + | | \ | | |
| + | | \ | | |
| + | | i_3 = Sense(o) v | |
| + | | | |
| + | o-----------------------------------------------------------o |
| + | Figure. Computation As Semiotic Transformation |
| + | |
| + | The Figure shows three distinct sign triples of the form <o, s, i>, where |
| + | o = ostensible objective = the observed, indicated, or intended situation. |
| + | |
| + | | A. <o, Logue(o), Model(o)> |
| + | | |
| + | | B. <o, Model(o), Tenor(o)> |
| + | | |
| + | | C. <o, Tenor(o), Sense(o)> |
| + | |
| + | Let us bring these several signs together in one place, |
| + | to compare and contrast their common and their diverse |
| + | characters, and to think about why we make such a fuss |
| + | about passing from one to the other in the first place. |
| + | |
| + | 1. Logue(o) = Consat.Log |
| + | o-----------------------------------------------------------------------o |
| + | | | |
| + | | (( pete_plays_guitar ),( pete_plays_sax ),( pete_plays_drums )) | |
| + | | (( paul_plays_guitar ),( paul_plays_sax ),( paul_plays_drums )) | |
| + | | (( jane_plays_guitar ),( jane_plays_sax ),( jane_plays_drums )) | |
| + | | | |
| + | | (( pete_plays_guitar ),( paul_plays_guitar ),( jane_plays_guitar )) | |
| + | | (( pete_plays_sax ),( paul_plays_sax ),( jane_plays_sax )) | |
| + | | (( pete_plays_drums ),( paul_plays_drums ),( jane_plays_drums )) | |
| + | | | |
| + | | (( pete_fears_13 ),( pete_fears_cats ),( pete_fears_height )) | |
| + | | (( paul_fears_13 ),( paul_fears_cats ),( paul_fears_height )) | |
| + | | (( jane_fears_13 ),( jane_fears_cats ),( jane_fears_height )) | |
| + | | | |
| + | | (( pete_fears_13 ),( paul_fears_13 ),( jane_fears_13 )) | |
| + | | (( pete_fears_cats ),( paul_fears_cats ),( jane_fears_cats )) | |
| + | | (( pete_fears_height ),( paul_fears_height ),( jane_fears_height )) | |
| + | | | |
| + | | (( | |
| + | | | |
| + | | ( pete_plays_guitar ) | |
| + | | ( pete_fears_height ) | |
| + | | | |
| + | | ( pete_plays_guitar pete_fears_height ) | |
| + | | ( paul_plays_guitar paul_fears_height ) | |
| + | | ( jane_plays_guitar jane_fears_height ) | |
| + | | | |
| + | | ( paul_fears_cats ) | |
| + | | ( paul_plays_sax ) | |
| + | | | |
| + | | ( pete_plays_sax pete_fears_cats ) | |
| + | | ( paul_plays_sax paul_fears_cats ) | |
| + | | ( jane_plays_sax jane_fears_cats ) | |
| + | | | |
| + | | ( pete_plays_drums pete_fears_13 ) | |
| + | | ( paul_plays_drums paul_fears_13 ) | |
| + | | ( jane_plays_drums jane_fears_13 ) | |
| + | | | |
| + | | ( pete_plays_drums pete_fears_height ) | |
| + | | ( paul_plays_drums paul_fears_height ) | |
| + | | ( jane_plays_drums jane_fears_height ) | |
| + | | | |
| + | | )) | |
| + | | | |
| + | o-----------------------------------------------------------------------o |
| + | |
| + | 2. Model(o) = Consat.Mod ><> http://suo.ieee.org/ontology/msg03718.html |
| + | |
| + | 3. Tenor(o) = Consat.Ten (Just The Gist Of It) |
| + | o-------------------------------------------------o |
| + | | (pete_plays_guitar ) | <01> - |
| + | | (pete_plays_sax ) | <02> - |
| + | | pete_plays_drums | <03> + |
| + | | (paul_plays_drums ) | <04> - |
| + | | (jane_plays_drums ) | <05> - |
| + | | paul_plays_guitar | <06> + |
| + | | (paul_plays_sax ) | <07> - |
| + | | (jane_plays_guitar ) | <08> - |
| + | | jane_plays_sax | <09> + |
| + | | (pete_fears_13 ) | <10> - |
| + | | pete_fears_cats | <11> + |
| + | | (pete_fears_height ) | <12> - |
| + | | (paul_fears_cats ) | <13> - |
| + | | (jane_fears_cats ) | <14> - |
| + | | paul_fears_13 | <15> + |
| + | | (paul_fears_height ) | <16> - |
| + | | (jane_fears_13 ) | <17> - |
| + | | jane_fears_height * | <18> + |
| + | o-------------------------------------------------o |
| + | |
| + | 4. Sense(o) = Consat.Sen |
| + | o-------------------------------------------------o |
| + | | pete_plays_drums | <03> |
| + | | paul_plays_guitar | <06> |
| + | | jane_plays_sax | <09> |
| + | | pete_fears_cats | <11> |
| + | | paul_fears_13 | <15> |
| + | | jane_fears_height | <18> |
| + | o-------------------------------------------------o |
| + | |
| + | As one proceeds through the subsessions of the Theme One Study session, |
| + | the computation transforms its larger "signs", in this case text files, |
| + | from one to the next, in the sequence: Logue, Model, Tenor, and Sense. |
| + | |
| + | Let us see if we can pin down, on sign-theoretic grounds, |
| + | why this very sort of exercise is so routinely necessary. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | We were in the middle of pursuing several questions about |
| + | sign relational transformations in general, in particular, |
| + | the following Example of a sign transformation that arose |
| + | in the process of setting up and solving a classical sort |
| + | of constraint satisfaction problem. |
| + | |
| + | o-----------------------------o-----------------------------o |
| + | | Objective Framework | Interpretive Framework | |
| + | o-----------------------------o-----------------------------o |
| + | | | |
| + | | s_1 = Logue(o) | | |
| + | | / | | |
| + | | / | | |
| + | | @ | | |
| + | | · \ | | |
| + | | · \ | | |
| + | | · i_1 = Model(o) v | |
| + | | · s_2 = Model(o) | | |
| + | | · / | | |
| + | | · / | | |
| + | | Object = o · · · · · · @ | | |
| + | | · \ | | |
| + | | · \ | | |
| + | | · i_2 = Tenor(o) v | |
| + | | · s_3 = Tenor(o) | | |
| + | | · / | | |
| + | | · / | | |
| + | | @ | | |
| + | | \ | | |
| + | | \ | | |
| + | | i_3 = Sense(o) v | |
| + | | | |
| + | o-----------------------------------------------------------o |
| + | Figure. Computation As Semiotic Transformation |
| + | |
| + | 1. Logue(o) = Consat.Log |
| + | o-----------------------------------------------------------------------o |
| + | | | |
| + | | (( pete_plays_guitar ),( pete_plays_sax ),( pete_plays_drums )) | |
| + | | (( paul_plays_guitar ),( paul_plays_sax ),( paul_plays_drums )) | |
| + | | (( jane_plays_guitar ),( jane_plays_sax ),( jane_plays_drums )) | |
| + | | | |
| + | | (( pete_plays_guitar ),( paul_plays_guitar ),( jane_plays_guitar )) | |
| + | | (( pete_plays_sax ),( paul_plays_sax ),( jane_plays_sax )) | |
| + | | (( pete_plays_drums ),( paul_plays_drums ),( jane_plays_drums )) | |
| + | | | |
| + | | (( pete_fears_13 ),( pete_fears_cats ),( pete_fears_height )) | |
| + | | (( paul_fears_13 ),( paul_fears_cats ),( paul_fears_height )) | |
| + | | (( jane_fears_13 ),( jane_fears_cats ),( jane_fears_height )) | |
| + | | | |
| + | | (( pete_fears_13 ),( paul_fears_13 ),( jane_fears_13 )) | |
| + | | (( pete_fears_cats ),( paul_fears_cats ),( jane_fears_cats )) | |
| + | | (( pete_fears_height ),( paul_fears_height ),( jane_fears_height )) | |
| + | | | |
| + | | (( | |
| + | | | |
| + | | ( pete_plays_guitar ) | |
| + | | ( pete_fears_height ) | |
| + | | | |
| + | | ( pete_plays_guitar pete_fears_height ) | |
| + | | ( paul_plays_guitar paul_fears_height ) | |
| + | | ( jane_plays_guitar jane_fears_height ) | |
| + | | | |
| + | | ( paul_fears_cats ) | |
| + | | ( paul_plays_sax ) | |
| + | | | |
| + | | ( pete_plays_sax pete_fears_cats ) | |
| + | | ( paul_plays_sax paul_fears_cats ) | |
| + | | ( jane_plays_sax jane_fears_cats ) | |
| + | | | |
| + | | ( pete_plays_drums pete_fears_13 ) | |
| + | | ( paul_plays_drums paul_fears_13 ) | |
| + | | ( jane_plays_drums jane_fears_13 ) | |
| + | | | |
| + | | ( pete_plays_drums pete_fears_height ) | |
| + | | ( paul_plays_drums paul_fears_height ) | |
| + | | ( jane_plays_drums jane_fears_height ) | |
| + | | | |
| + | | )) | |
| + | | | |
| + | o-----------------------------------------------------------------------o |
| + | |
| + | 2. Model(o) = Consat.Mod ><> http://suo.ieee.org/ontology/msg03718.html |
| + | |
| + | 3. Tenor(o) = Consat.Ten (Just The Gist Of It) |
| + | o-------------------------------------------------o |
| + | | (pete_plays_guitar ) | <01> - |
| + | | (pete_plays_sax ) | <02> - |
| + | | pete_plays_drums | <03> + |
| + | | (paul_plays_drums ) | <04> - |
| + | | (jane_plays_drums ) | <05> - |
| + | | paul_plays_guitar | <06> + |
| + | | (paul_plays_sax ) | <07> - |
| + | | (jane_plays_guitar ) | <08> - |
| + | | jane_plays_sax | <09> + |
| + | | (pete_fears_13 ) | <10> - |
| + | | pete_fears_cats | <11> + |
| + | | (pete_fears_height ) | <12> - |
| + | | (paul_fears_cats ) | <13> - |
| + | | (jane_fears_cats ) | <14> - |
| + | | paul_fears_13 | <15> + |
| + | | (paul_fears_height ) | <16> - |
| + | | (jane_fears_13 ) | <17> - |
| + | | jane_fears_height * | <18> + |
| + | o-------------------------------------------------o |
| + | |
| + | 4. Sense(o) = Consat.Sen |
| + | o-------------------------------------------------o |
| + | | pete_plays_drums | <03> |
| + | | paul_plays_guitar | <06> |
| + | | jane_plays_sax | <09> |
| + | | pete_fears_cats | <11> |
| + | | paul_fears_13 | <15> |
| + | | jane_fears_height | <18> |
| + | o-------------------------------------------------o |
| + | |
| + | We can worry later about the proper use of quotation marks |
| + | in discussing such a case, where the file name "Yada.Yak" |
| + | denotes a piece of text that expresses a proposition that |
| + | describes an objective situation or an intentional object, |
| + | but whatever the case it is clear that we are knee & neck |
| + | deep in a sign relational situation of a modest complexity. |
| + | |
| + | I think that the right sort of analogy might help us |
| + | to sort it out, or at least to tell what's important |
| + | from the things that are less so. The paradigm that |
| + | comes to mind for me is the type of context in maths |
| + | where we talk about the "locus" or the "solution set" |
| + | of an equation, and here we think of the equation as |
| + | denoting its solution set or describing a locus, say, |
| + | a point or a curve or a surface or so on up the scale. |
| + | |
| + | In this figure of speech, we might say for instance: |
| + | |
| + | | o is |
| + | | what "x^3 - 3x^2 + 3x - 1 = 0" denotes is |
| + | | what "(x-1)^3 = 0" denotes is |
| + | | what "1" denotes |
| + | | is 1. |
| + | |
| + | Making explicit the assumptive interpretations |
| + | that the context probably enfolds in this case, |
| + | we assume this description of the solution set: |
| + | |
| + | {x in the Reals : x^3 - 3x^2 + 3x -1 = 0} = {1}. |
| + | |
| + | In sign relational terms, we have the 3-tuples: |
| + | |
| + | | <o, "x^3 - 3x^2 + 3x - 1 = 0", "(x-1)^3 = 0"> |
| + | | |
| + | | <o, "(x-1)^3 = 0", "1"> |
| + | | |
| + | | <o, "1", "1"> |
| + | |
| + | As it turns out we discover that the |
| + | object o was really just 1 all along. |
| + | |
| + | But why do we put ourselves through the rigors of these |
| + | transformations at all? If 1 is what we mean, why not |
| + | just say "1" in the first place and be done with it? |
| + | A person who asks a question like that has forgetten |
| + | how we keep getting ourselves into these quandaries, |
| + | and who it is that assigns the problems, for it is |
| + | Nature herself who is the taskmistress here and the |
| + | problems are set in the manner that she determines, |
| + | not in the style to which we would like to become |
| + | accustomed. The best that we can demand of our |
| + | various and sundry calculi is that they afford |
| + | us with the nets and the snares more readily |
| + | to catch the shape of the problematic game |
| + | as it flies up before us on its own wings, |
| + | and only then to tame it to the amenable |
| + | demeanors that we find to our liking. |
| + | |
| + | In sum, the first place is not ours to take. |
| + | We are but poor second players in this game. |
| + | |
| + | That understood, I can now lay out our present Example |
| + | along the lines of this familiar mathematical exercise. |
| + | |
| + | | o is |
| + | | what Consat.Log denotes is |
| + | | what Consat.Mod denotes is |
| + | | what Consat.Ten denotes is |
| + | | what Consat.Sen denotes. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | It will be good to keep this picture before us a while longer: |
| + | |
| + | o-----------------------------o-----------------------------o |
| + | | Objective Framework | Interpretive Framework | |
| + | o-----------------------------o-----------------------------o |
| + | | | |
| + | | s_1 = Logue(o) | | |
| + | | / | | |
| + | | / | | |
| + | | @ | | |
| + | | · \ | | |
| + | | · \ | | |
| + | | · i_1 = Model(o) v | |
| + | | · s_2 = Model(o) | | |
| + | | · / | | |
| + | | · / | | |
| + | | Object = o · · · · · · @ | | |
| + | | · \ | | |
| + | | · \ | | |
| + | | · i_2 = Tenor(o) v | |
| + | | · s_3 = Tenor(o) | | |
| + | | · / | | |
| + | | · / | | |
| + | | @ | | |
| + | | \ | | |
| + | | \ | | |
| + | | i_3 = Sense(o) v | |
| + | | | |
| + | o-----------------------------------------------------------o |
| + | Figure. Computation As Semiotic Transformation |
| + | |
| + | The labels that decorate the syntactic plane and indicate |
| + | the semiotic transitions in the interpretive panel of the |
| + | framework point us to text files whose contents rest here: |
| + | |
| + | http://suo.ieee.org/ontology/msg03722.html |
| + | |
| + | The reason that I am troubling myself -- and no doubt you -- |
| + | with the details of this Example is because it highlights |
| + | a number of the thistles that we will have to grasp if we |
| + | ever want to escape from the traps of YARNBOL and YARWARS |
| + | in which so many of our fairweather fiends are seeking to |
| + | ensnare us, and not just us -- the whole web of the world. |
| + | |
| + | YARNBOL = Yet Another Roman Numeral Based Ontology Language. |
| + | YARWARS = Yet Another Representation Without A Reasoning System. |
| + | |
| + | In order to avoid this, or to reverse the trend once it gets started, |
| + | we just have to remember what a dynamic living process a computation |
| + | really is, precisely because it is meant to serve as an iconic image |
| + | of dynamic, deliberate, purposeful transformations that we are bound |
| + | to go through and to carry out in a hopeful pursuit of the solutions |
| + | to the many real live problems that life and society place before us. |
| + | So I take it rather seriously. |
| + | |
| + | Okay, back to the grindstone. |
| + | |
| + | The question is: "Why are these trips necessary?" |
| + | |
| + | How come we don't just have one proper expression |
| + | for each situation under the sun, or all possible |
| + | suns, I guess, for some, and just use that on any |
| + | appearance, instance, occasion of that situation? |
| + | |
| + | Why is it ever necessary to begin with an obscure description |
| + | of a situation? -- for that is exactly what the propositional |
| + | expression caled "Logue(o)", for Example, the Consat.Log file, |
| + | really is. |
| + | |
| + | Maybe I need to explain that first. |
| + | |
| + | The first three items of syntax -- Logue(o), Model(o), Tenor(o) -- |
| + | are all just so many different propositional expressions that |
| + | denote one and the same logical-valued function p : X -> %B%, |
| + | and one whose abstract image we may well enough describe as |
| + | a boolean function of the abstract type q : %B%^k -> %B%, |
| + | where k happens to be 18 in the present Consat Example. |
| + | |
| + | If we were to write out the truth table for q : %B%^18 -> %B% |
| + | it would take 2^18 = 262144 rows. Using the bold letter #x# |
| + | for a coordinate tuple, writing #x# = <x_1, ..., x_18>, each |
| + | row of the table would have the form <x_1, ..., x_18, q(#x#)>. |
| + | And the function q is such that all rows evalue to %0% save 1. |
| + | |
| + | Each of the four different formats expresses this fact about q |
| + | in its own way. The first three are logically equivalent, and |
| + | the last one is the maximally determinate positive implication |
| + | of what the others all say. |
| + | |
| + | From this point of view, the logical computation that we went through, |
| + | in the sequence Logue, Model, Tenor, Sense, was a process of changing |
| + | from an obscure sign of the objective proposition to a more organized |
| + | arrangement of its satisfying or unsatisfying interpretations, to the |
| + | most succinct possible expression of the same meaning, to an adequate |
| + | positive projection of it that is useful enough in the proper context. |
| + | |
| + | This is the sort of mill -- it's called "computation" -- that we have |
| + | to be able to put our representations through on a recurrent, regular, |
| + | routine basis, that is, if we expect them to have any utility at all. |
| + | And it is only when we have started to do that in genuinely effective |
| + | and efficient ways, that we can even begin to think about facilitating |
| + | any bit of qualitative conceptual analysis through computational means. |
| + | |
| + | And as far as the qualitative side of logical computation |
| + | and conceptual analysis goes, we have barely even started. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | We are contemplating the sequence of initial and normal forms |
| + | for the Consat problem and we have noted the following system |
| + | of logical relations, taking the enchained expressions of the |
| + | objective situation o in a pairwise associated way, of course: |
| + | |
| + | Logue(o) <=> Model(o) <=> Tenor(o) => Sense(o). |
| + | |
| + | The specifics of the propositional expressions are cited here: |
| + | |
| + | http://suo.ieee.org/ontology/msg03722.html |
| + | |
| + | If we continue to pursue the analogy that we made with the form |
| + | of mathematical activity commonly known as "solving equations", |
| + | then there are many salient features of this type of logical |
| + | problem solving endeavor that suddenly leap into the light. |
| + | |
| + | First of all, we notice the importance of "equational reasoning" |
| + | in mathematics, by which I mean, not just the quantitative type |
| + | of equation that forms the matter of the process, but also the |
| + | qualitative type of equation, or the "logical equivalence", |
| + | that connects each expression along the way, right up to |
| + | the penultimate stage, when we are satisfied in a given |
| + | context to take a projective implication of the total |
| + | knowledge of the situation that we have been taking |
| + | some pains to preserve at every intermediate stage |
| + | of the game. |
| + | |
| + | This general pattern or strategy of inference, working its way through |
| + | phases of "equational" or "total information preserving" inference and |
| + | phases of "implicational" or "selective information losing" inference, |
| + | is actually very common throughout mathematics, and I have in mind to |
| + | examine its character in greater detail and in a more general setting. |
| + | |
| + | Just as the barest hint of things to come along these lines, you might |
| + | consider the question of what would constitute the equational analogue |
| + | of modus ponens, in other words the scheme of inference that goes from |
| + | x and x=>y to y. Well the answer is a scheme of inference that passes |
| + | from x and x=>y to x&y, and then being reversible, back again. I will |
| + | explore the rationale and the utility of this gambit in future reports. |
| + | |
| + | One observation that we can make already at this point, |
| + | however, is that these schemes of equational reasoning, |
| + | or reversible inference, remain poorly developed among |
| + | our currently prevailing styles of inference in logic, |
| + | their potentials for applied logical software hardly |
| + | being broached in our presently available systems. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | |
| + | Extra Examples |
| + | |
| + | 1. Propositional logic example. |
| + | Files: Alpha.lex + Prop.log |
| + | Ref: [Cha, 20, Example 2.12] |
| + | |
| + | 2. Chemical synthesis problem. |
| + | Files: Chem.* |
| + | Ref: [Cha, 21, Example 2.13] |
| + | |
| + | 3. N Queens problem. |
| + | Files: Queen*.*, Q8.*, Q5.* |
| + | Refs: [BaC, 166], [VaH, 122], [Wir, 143]. |
| + | Notes: Only the 5 Queens example will run in 640K memory. |
| + | Use the "Queen.lex" file to load the "Q5.eg*" log files. |
| + | |
| + | 4. Five Houses puzzle. |
| + | Files: House.* |
| + | Ref: [VaH, 132]. |
| + | Notes: Will not run in 640K memory. |
| + | |
| + | 5. Graph coloring example. |
| + | Files: Color.* |
| + | Ref: [Wil, 196]. |
| + | |
| + | 6. Examples of Cook's Theorem in computational complexity, |
| + | that propositional satisfiability is NP-complete. |
| + | |
| + | Files: StiltN.* = "Space and Time Limited Turing Machine", |
| + | with N units of space and N units of time. |
| + | StuntN.* = "Space and Time Limited Turing Machine", |
| + | for computing the parity of a bit string, |
| + | with Number of Tape cells of input equal to N. |
| + | Ref: [Wil, 188-201]. |
| + | Notes: Can only run Turing machine example for input of size 2. |
| + | Since the last tape cell is used for an end-of-file marker, |
| + | this amounts to only one significant digit of computation. |
| + | Use the "Stilt3.lex" file to load the "Stunt2.egN" files. |
| + | Their Sense file outputs appear on the "Stunt2.seN" files. |
| + | |
| + | 7. Fabric knowledge base. |
| + | Files: Fabric.*, Fab.* |
| + | Ref: [MaW, 8-16]. |
| + | |
| + | 8. Constraint Satisfaction example. |
| + | Files: Consat1.*, Consat2.* |
| + | Ref: [Win, 449, Exercise 3-9]. |
| + | Notes: Attributed to Kenneth D. Forbus. |
| + | |
| + | References |
| + | |
| + | | Angluin, Dana, |
| + | |"Learning with Hints", in |
| + | |'Proceedings of the 1988 Workshop on Computational Learning Theory', |
| + | | edited by D. Haussler & L. Pitt, Morgan Kaufmann, San Mateo, CA, 1989. |
| + | |
| + | | Ball, W.W. Rouse, & Coxeter, H.S.M., |
| + | |'Mathematical Recreations and Essays', 13th ed., |
| + | | Dover, New York, NY, 1987. |
| + | |
| + | | Chang, Chin-Liang & Lee, Richard Char-Tung, |
| + | |'Symbolic Logic and Mechanical Theorem Proving', |
| + | | Academic Press, New York, NY, 1973. |
| + | |
| + | | Denning, Peter J., Dennis, Jack B., and Qualitz, Joseph E., |
| + | |'Machines, Languages, and Computation', |
| + | | Prentice-Hall, Englewood Cliffs, NJ, 1978. |
| + | |
| + | | Edelman, Gerald M., |
| + | |'Topobiology: An Introduction to Molecular Embryology', |
| + | | Basic Books, New York, NY, 1988. |
| + | |
| + | | Lloyd, J.W., |
| + | |'Foundations of Logic Programming', |
| + | | Springer-Verlag, Berlin, 1984. |
| + | |
| + | | Maier, David & Warren, David S., |
| + | |'Computing with Logic: Logic Programming with Prolog', |
| + | | Benjamin/Cummings, Menlo Park, CA, 1988. |
| + | |
| + | | McClelland, James L. and Rumelhart, David E., |
| + | |'Explorations in Parallel Distributed Processing: |
| + | | A Handbook of Models, Programs, and Exercises', |
| + | | MIT Press, Cambridge, MA, 1988. |
| + | |
| + | | Peirce, Charles Sanders, |
| + | |'Collected Papers of Charles Sanders Peirce', |
| + | | edited by Charles Hartshorne, Paul Weiss, & Arthur W. Burks, |
| + | | Harvard University Press, Cambridge, MA, 1931-1960. |
| + | |
| + | | Peirce, Charles Sanders, |
| + | |'The New Elements of Mathematics', |
| + | | edited by Carolyn Eisele, Mouton, The Hague, 1976. |
| + | |
| + | |'Charles S. Peirce: Selected Writings; Values in a Universe of Chance', |
| + | | edited by Philip P. Wiener, Dover, New York, NY, 1966. |
| + | |
| + | | Spencer Brown, George, |
| + | |'Laws of Form', |
| + | | George Allen & Unwin, London, UK, 1969. |
| + | |
| + | | Van Hentenryck, Pascal, |
| + | |'Constraint Satisfaction in Logic Programming', |
| + | | MIT Press, Cambridge, MA, 1989. |
| + | |
| + | | Wilf, Herbert S., |
| + | |'Algorithms and Complexity', |
| + | | Prentice-Hall, Englewood Cliffs, NJ, 1986. |
| + | |
| + | | Winston, Patrick Henry, |
| + | |'Artificial Intelligence, 2nd ed., |
| + | | Addison-Wesley, Reading, MA, 1984. |
| + | |
| + | | Wirth, Niklaus, |
| + | |'Algorithms + Data Structures = Programs', |
| + | | Prentice-Hall, Englewood Cliffs, NJ, 1976. |
| + | |
| + | o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o~~~~~~~~~o |
| + | </pre> |
| + | |
| + | |
| ==Fragmata== | | ==Fragmata== |
| | | |