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| ==Expository Note 13== | | ==Expository Note 13== |
| | | |
− | <pre>
| + | '''3.3. Logical Cacti''' |
− | 3.3. Logical Cacti | + | |
| + | Up till now we've been working to hammer out a two-edged sword of syntax, honing the syntax of ''painted and rooted cacti and expressions'' (PARCAE), and turning it to use in taming the syntax of two-level formal languages. |
| + | |
| + | But the purpose of a logical syntax is to support a logical semantics, which means, for starters, to bear interpretation as sentential signs that can denote objective propositions about some universe of objects. |
| + | |
| + | One of the difficulties that we face in this discussion is that the words ''interpretation'', ''meaning'', ''semantics'', and so on will have so many different meanings from one moment to the next of their use. A dedicated neologician might be able to think up distinctive names for all of the aspects of meaning and all of the approaches to them that will concern us here, but I will just have to do the best that I can with the common lot of ambiguous terms, leaving it to context and the intelligent interpreter to sort it out as much as possible. |
| | | |
− | Up till now we've been working to hammer out a two-edged sword of syntax,
| + | As it happens, the language of cacti is so abstract that it can bear at least two different interpretations as logical sentences denoting logical propositions. The two interpretations that I know about are descended from the ones that C.S. Peirce called the ''entitative'' and the ''existential'' interpretations of his systems of graphical logics. For our present aims, I shall briefly introduce the alternatives and then quickly move to the existential interpretation of logical cacti. |
− | honing the syntax of "painted and rooted cacti and expressions" (PARCAE),
| |
− | and turning it to use in taming the syntax of two-level formal languages. | |
| | | |
− | But the purpose of a logical syntax is to support a logical semantics,
| + | 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. |
− | which means, for starters, to bear interpretation as sentential signs
| |
− | that can denote objective propositions about some universe of objects.
| |
| | | |
− | One of the difficulties that we face in this discussion is that the
| + | <br> |
− | words "interpretation", "meaning", "semantics", and so on will have
| |
− | so many different meanings from one moment to the next of their use.
| |
− | A dedicated neologician might be able to think up distinctive names
| |
− | for all of the aspects of meaning and all of the approaches to them
| |
− | that will concern us here, but I will just have to do the best that
| |
− | I can with the common lot of ambiguous terms, leaving it to context
| |
− | and the intelligent interpreter to sort it out as much as possible.
| |
| | | |
− | As it happens, the language of cacti is so abstract that it can bear
| + | {| align="center" border="1" cellpadding="6" cellspacing="0" style="background:#f8f8ff; text-align:center; width:90%" |
− | at least two different interpretations as logical sentences denoting
| + | |+ <math>\text{Table 13.}~~\text{Existential Interpretation}</math> |
− | logical propositions. The two interpretations that I know about are
| + | |- style="background:#f0f0ff" |
− | descended from the ones that C.S. Peirce called the "entitative" and
| + | | <math>\text{Cactus Graph}\!</math> |
− | the "existential" interpretations of his systems of graphical logics.
| + | | <math>\text{Cactus Expression}\!</math> |
− | For our present aims, I shall briefly introduce the alternatives and
| + | | <math>\text{Interpretation}\!</math> |
− | then quickly move to the existential interpretation of logical cacti.
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>{}^{\backprime\backprime}\texttt{~}{}^{\prime\prime}</math> |
| + | | <math>\operatorname{true}.</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | o | |
| + | | | | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{(~)}</math> |
| + | | <math>\operatorname{false}.</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>a\!</math> |
| + | | <math>a.\!</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a | |
| + | | o | |
| + | | | | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{(} a \texttt{)}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | \tilde{a} |
| + | \\[6pt] |
| + | a^\prime |
| + | \\[6pt] |
| + | \lnot a |
| + | \\[6pt] |
| + | \operatorname{not}~ a. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b c | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>a~b~c</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | a \land b \land c |
| + | \\[6pt] |
| + | a ~\operatorname{and}~ b ~\operatorname{and}~ c. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b c | |
| + | | o o o | |
| + | | \|/ | |
| + | | o | |
| + | | | | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{((} a \texttt{)(} b \texttt{)(} c \texttt{))}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | a \lor b \lor c |
| + | \\[6pt] |
| + | a ~\operatorname{or}~ b ~\operatorname{or}~ c. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b | |
| + | | o---o | |
| + | | | | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{(} a \texttt{(} b \texttt{))}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | a \Rightarrow b |
| + | \\[6pt] |
| + | a ~\operatorname{implies}~ b. |
| + | \\[6pt] |
| + | \operatorname{if}~ a ~\operatorname{then}~ b. |
| + | \\[6pt] |
| + | \operatorname{not}~ a ~\operatorname{without}~ b. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b | |
| + | | o---o | |
| + | | \ / | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{(} a, b \texttt{)}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | a + b |
| + | \\[6pt] |
| + | a \neq b |
| + | \\[6pt] |
| + | a ~\operatorname{exclusive-or}~ b. |
| + | \\[6pt] |
| + | a ~\operatorname{not~equal~to}~ b. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b | |
| + | | o---o | |
| + | | \ / | |
| + | | o | |
| + | | | | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{((} a, b \texttt{))}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | a = b |
| + | \\[6pt] |
| + | a \iff b |
| + | \\[6pt] |
| + | a ~\operatorname{equals}~ b. |
| + | \\[6pt] |
| + | a ~\operatorname{if~and~only~if}~ b. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b c | |
| + | | o--o--o | |
| + | | \ / | |
| + | | \ / | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{(} a, b, c \texttt{)}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | \operatorname{just~one~of} |
| + | \\ |
| + | a, b, c |
| + | \\ |
| + | \operatorname{is~false}. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b c | |
| + | | o o o | |
| + | | | | | | |
| + | | o--o--o | |
| + | | \ / | |
| + | | \ / | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{((} a \texttt{)}, \texttt{(} b \texttt{)}, \texttt{(} c \texttt{))}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | \operatorname{just~one~of} |
| + | \\ |
| + | a, b, c |
| + | \\ |
| + | \operatorname{is~true}. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | b c | |
| + | | o o | |
| + | | a | | | |
| + | | o--o--o | |
| + | | \ / | |
| + | | \ / | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{(} a, \texttt{(} b \texttt{)}, \texttt{(} c \texttt{))}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | \operatorname{genus}~ a ~\operatorname{of~species}~ b, c. |
| + | \\[6pt] |
| + | \operatorname{partition}~ a ~\operatorname{into}~ b, c. |
| + | \\[6pt] |
| + | \operatorname{pie}~ a ~\operatorname{of~slices}~ b, c. |
| + | \end{matrix}</math> |
| + | |} |
| | | |
− | Table 13 illustrates the "existential interpretation"
| + | <br> |
− | of cactus graphs and cactus expressions by providing
| |
− | English translations for a few of the most basic and
| |
− | commonly occurring forms.
| |
| | | |
− | Table 13. The Existential Interpretation | + | Table 14 illustrates the ''entitative interpretation'' of cactus graphs and cactus expressions by providing English translations for a few of the most basic and commonly occurring forms. |
− | o----o-------------------o-------------------o-------------------o
| |
− | | Ex | Cactus Graph | Cactus Expression | Existential |
| |
− | | | | | Interpretation |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | 1 | @ | " " | true. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | o | | |
| |
− | | | | | | |
| |
− | | 2 | @ | ( ) | untrue. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | a | | |
| |
− | | 3 | @ | a | a. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | a | | |
| |
− | | | o | | |
| |
− | | | | | | |
| |
− | | 4 | @ | (a) | not a. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | a b c | | |
| |
− | | 5 | @ | a b c | a and b and c. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | a b c | | |
| |
− | | | o o o | | |
| |
− | | | \|/ | | |
| |
− | | | o | | |
| |
− | | | | | | |
| |
− | | 6 | @ | ((a)(b)(c)) | a or b or c. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | | | a implies b. |
| |
− | | | a b | | |
| |
− | | | o---o | | if a then b. |
| |
− | | | | | | |
| |
− | | 7 | @ | ( a (b)) | no a sans b. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | a b | | |
| |
− | | | o---o | | a exclusive-or b. |
| |
− | | | \ / | | |
| |
− | | 8 | @ | ( a , b ) | a not equal to b. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | a b | | |
| |
− | | | o---o | | |
| |
− | | | \ / | | |
| |
− | | | o | | a if & only if b. |
| |
− | | | | | | |
| |
− | | 9 | @ | (( a , b )) | a equates with b. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | a b c | | |
| |
− | | | o--o--o | | |
| |
− | | | \ / | | |
| |
− | | | \ / | | just one false |
| |
− | | 10 | @ | ( a , b , c ) | out of a, b, c. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
− | | | | | |
| |
− | | | a b c | | |
| |
− | | | o o o | | |
| |
− | | | | | | | | |
| |
− | | | o--o--o | | |
| |
− | | | \ / | | |
| |
− | | | \ / | | just one true |
| |
− | | 11 | @ | ((a),(b),(c)) | among a, b, c. |
| |
− | | | | | |
| |
− | o----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: |
| |
− | | 12 | @ | ( a ,(b),(c)) | slices b, c. |
| |
− | | | | | |
| |
− | o----o-------------------o-------------------o-------------------o
| |
| | | |
− | Table 14 illustrates the "entitative interpretation"
| + | <br> |
− | of cactus graphs and cactus expressions by providing
| |
− | English translations for a few of the most basic and
| |
− | commonly occurring forms.
| |
| | | |
− | Table 14. The Entitative Interpretation | + | {| align="center" border="1" cellpadding="6" cellspacing="0" style="background:#f8f8ff; text-align:center; width:90%" |
− | o----o-------------------o-------------------o-------------------o
| + | |+ <math>\text{Table 14.}~~\text{Entitative Interpretation}</math> |
− | | En | Cactus Graph | Cactus Expression | Entitative | | + | |- style="background:#f0f0ff" |
− | | | | | Interpretation | | + | | <math>\text{Cactus Graph}\!</math> |
− | o----o-------------------o-------------------o-------------------o
| + | | <math>\text{Cactus Expression}\!</math> |
− | | | | | |
| + | | <math>\text{Interpretation}\!</math> |
− | | 1 | @ | " " | untrue. |
| + | |- |
− | | | | | |
| + | | |
− | o----o-------------------o-------------------o-------------------o
| + | <pre> |
− | | | | | |
| + | o-------------------o |
− | | | o | | |
| + | | | |
− | | | | | | |
| + | | @ | |
− | | 2 | @ | ( ) | true. |
| + | | | |
− | | | | | |
| + | o-------------------o |
− | o----o-------------------o-------------------o-------------------o
| + | </pre> |
− | | | | | |
| + | | <math>{}^{\backprime\backprime}\texttt{~}{}^{\prime\prime}</math> |
− | | | a | | |
| + | | <math>\operatorname{false}.</math> |
− | | 3 | @ | a | a. |
| + | |- |
− | | | | | |
| + | | |
− | o----o-------------------o-------------------o-------------------o
| + | <pre> |
− | | | | | |
| + | o-------------------o |
− | | | a | | |
| + | | | |
− | | | o | | |
| + | | o | |
− | | | | | | |
| + | | | | |
− | | 4 | @ | (a) | not a. |
| + | | @ | |
− | | | | | |
| + | | | |
− | o----o-------------------o-------------------o-------------------o
| + | o-------------------o |
− | | | | | | | + | </pre> |
− | | | a b c | | |
| + | | <math>\texttt{(~)}</math> |
− | | 5 | @ | a b c | a or b or c. |
| + | | <math>\operatorname{true}.</math> |
− | | | | | | | + | |- |
− | o----o-------------------o-------------------o-------------------o
| + | | |
− | | | | | |
| + | <pre> |
− | | | a b c | | |
| + | o-------------------o |
− | | | o o o | | |
| + | | | |
− | | | \|/ | | |
| + | | a | |
− | | | o | | |
| + | | @ | |
− | | | | | | |
| + | | | |
− | | 6 | @ | ((a)(b)(c)) | a and b and c. |
| + | o-------------------o |
− | | | | | |
| + | </pre> |
− | o----o-------------------o-------------------o-------------------o
| + | | <math>a\!</math> |
− | | | | | |
| + | | <math>a.\!</math> |
− | | | | | a implies b. | | + | |- |
− | | | | | |
| + | | |
− | | | o a | | if a then b. |
| + | <pre> |
− | | | | | | |
| + | o-------------------o |
− | | 7 | @ b | (a) b | not a, or b. |
| + | | | |
− | | | | | | | + | | a | |
− | o----o-------------------o-------------------o-------------------o
| + | | o | |
− | | | | | |
| + | | | | |
− | | | a b | | |
| + | | @ | |
− | | | o---o | | a if & only if b. |
| + | | | |
− | | | \ / | | |
| + | o-------------------o |
− | | 8 | @ | ( a , b ) | a equates with b. | | + | </pre> |
− | | | | | |
| + | | <math>\texttt{(} a \texttt{)}</math> |
− | o----o-------------------o-------------------o-------------------o
| + | | |
− | | | | | |
| + | <math>\begin{matrix} |
− | | | a b | | | | + | \tilde{a} |
− | | | o---o | | |
| + | \\[6pt] |
− | | | \ / | | |
| + | a^\prime |
− | | | o | | a exclusive-or b. |
| + | \\[6pt] |
− | | | | | | |
| + | \lnot a |
− | | 9 | @ | (( a , b )) | a not equal to b. |
| + | \\[6pt] |
− | | | | | | | + | \operatorname{not}~ a. |
− | o----o-------------------o-------------------o-------------------o
| + | \end{matrix}</math> |
− | | | | | |
| + | |- |
− | | | a b c | | | | + | | |
− | | | o--o--o | | |
| + | <pre> |
− | | | \ / | | |
| + | o-------------------o |
− | | | \ / | | not just one true | | + | | | |
− | | 10 | @ | ( a , b , c ) | out of a, b, c. |
| + | | a b c | |
− | | | | | |
| + | | @ | |
− | o----o-------------------o-------------------o-------------------o
| + | | | |
− | | | | | |
| + | o-------------------o |
− | | | a b c | | | | + | </pre> |
− | | | o--o--o | | |
| + | | <math>a~b~c</math> |
− | | | \ / | | |
| + | | |
− | | | \ / | | |
| + | <math>\begin{matrix} |
− | | | o | | |
| + | a \lor b \lor c |
− | | | | | | just one true |
| + | \\[6pt] |
− | | 11 | @ | (( a , b , c )) | among a, b, c. |
| + | a ~\operatorname{or}~ b ~\operatorname{or}~ c. |
− | | | | | | | + | \end{matrix}</math> |
− | o----o-------------------o-------------------o-------------------o
| + | |- |
− | | | | | |
| + | | |
− | | | a | | | | + | <pre> |
− | | | o | | genus a over |
| + | o-------------------o |
− | | | | b c | | species b, c. |
| + | | | |
− | | | o--o--o | | | | + | | a b c | |
− | | | \ / | | partition a |
| + | | o o o | |
− | | | \ / | | among b & c. |
| + | | \|/ | |
− | | | o | | |
| + | | o | |
− | | | | | | whole pie a: |
| + | | | | |
− | | 12 | @ | (((a), b , c )) | slices b, c. |
| + | | @ | |
− | | | | | |
| + | | | |
− | o----o-------------------o-------------------o-------------------o
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{((} a \texttt{)(} b \texttt{)(} c \texttt{))}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | a \land b \land c |
| + | \\[6pt] |
| + | a ~\operatorname{and}~ b ~\operatorname{and}~ c. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | o a | |
| + | | | | |
| + | | @ b | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{(} a \texttt{)} b</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | a \Rightarrow b |
| + | \\[6pt] |
| + | a ~\operatorname{implies}~ b. |
| + | \\[6pt] |
| + | \operatorname{if}~ a ~\operatorname{then}~ b. |
| + | \\[6pt] |
| + | \operatorname{not}~ a, ~\operatorname{or}~ b. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b | |
| + | | o---o | |
| + | | \ / | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| </pre> | | </pre> |
| + | | <math>\texttt{(} a, b \texttt{)}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | a = b |
| + | \\[6pt] |
| + | a \iff b |
| + | \\[6pt] |
| + | a ~\operatorname{equals}~ b. |
| + | \\[6pt] |
| + | a ~\operatorname{if~and~only~if}~ b. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b | |
| + | | o---o | |
| + | | \ / | |
| + | | o | |
| + | | | | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{((} a, b \texttt{))}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | a + b |
| + | \\[6pt] |
| + | a \neq b |
| + | \\[6pt] |
| + | a ~\operatorname{exclusive-or}~ b. |
| + | \\[6pt] |
| + | a ~\operatorname{not~equal~to}~ b. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b c | |
| + | | o--o--o | |
| + | | \ / | |
| + | | \ / | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{(} a, b, c \texttt{)}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | \operatorname{not~just~one~of} |
| + | \\ |
| + | a, b, c |
| + | \\ |
| + | \operatorname{is~true}. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a b c | |
| + | | o--o--o | |
| + | | \ / | |
| + | | \ / | |
| + | | o | |
| + | | | | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{((} a, b, c \texttt{))}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | \operatorname{just~one~of} |
| + | \\ |
| + | a, b, c |
| + | \\ |
| + | \operatorname{is~true}. |
| + | \end{matrix}</math> |
| + | |- |
| + | | |
| + | <pre> |
| + | o-------------------o |
| + | | | |
| + | | a | |
| + | | o | |
| + | | | b c | |
| + | | o--o--o | |
| + | | \ / | |
| + | | \ / | |
| + | | o | |
| + | | | | |
| + | | @ | |
| + | | | |
| + | o-------------------o |
| + | </pre> |
| + | | <math>\texttt{(((} a \texttt{)}, b, c \texttt{))}</math> |
| + | | |
| + | <math>\begin{matrix} |
| + | \operatorname{genus}~ a ~\operatorname{of~species}~ b, c. |
| + | \\[6pt] |
| + | \operatorname{partition}~ a ~\operatorname{into}~ b, c. |
| + | \\[6pt] |
| + | \operatorname{pie}~ a ~\operatorname{of~slices}~ b, c. |
| + | \end{matrix}</math> |
| + | |} |
| + | |
| + | <br> |
| | | |
| ==Expository Note 14== | | ==Expository Note 14== |