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{{DISPLAYTITLE:Differential Logic and Dynamic Systems}}
{{DISPLAYTITLE:Differential Logic and Dynamic Systems 2.0}}
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| align="left" | ''Stand and unfold yourself.''
| align="right" | Hamlet: Francsico—1.1.2
|}
This article develops a differential extension of [[propositional calculus]] and applies it to a context of problems arising in dynamic systems. The work pursued here is coordinated with a parallel application that focuses on neural network systems, but the dependencies are arranged to make the present article the main and the more self-contained work, to serve as a conceptual frame and a technical background for the network project.
This article develops a differential extension of [[propositional calculus]] and applies it to a context of problems arising in dynamic systems. The work pursued here is coordinated with a parallel application that focuses on neural network systems, but the dependencies are arranged to make the present article the main and the more self-contained work, to serve as a conceptual frame and a technical background for the network project.
==A Functional Conception of Propositional Calculus==
==A Functional Conception of Propositional Calculus==
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Out of the dimness opposite equals advance . . . .<br>
Always substance and increase,<br>
Always substance and increase,<br>
Always a knit of identity . . . . always distinction . . . .<br>
Always a knit of identity . . . . always distinction . . . .<br>
always a breed of life.</p>
always a breed of life.
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| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 28]
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In the general case, we start with a set of logical features {''a''<sub>1</sub>, …, ''a''<sub>''n''</sub>} that represent properties of objects or propositions about the world. In concrete examples the features {''a''<sub>''i''</sub>} commonly appear as capital letters from an ''alphabet'' like {''A'', ''B'', ''C'', …} or as meaningful words from a linguistic ''vocabulary'' of codes. This language can be drawn from any sources, whether natural, technical, or artificial in character and interpretation. In the application to dynamic systems we tend to use the letters {''x''<sub>1</sub>, …, ''x''<sub>''n''</sub>} as our coordinate propositions, and to interpret them as denoting properties of a system's ''state'', that is, as propositions about its location in configuration space. Because I have to consider non-deterministic systems from the outset, I often use the word ''state'' in a loose sense, to denote the position or configuration component of a contemplated state vector, whether or not it ever gets a deterministic completion.
In the general case, we start with a set of logical features {''a''<sub>1</sub>, …, ''a''<sub>''n''</sub>} that represent properties of objects or propositions about the world. In concrete examples the features {''a''<sub>''i''</sub>} commonly appear as capital letters from an ''alphabet'' like {''A'', ''B'', ''C'', …} or as meaningful words from a linguistic ''vocabulary'' of codes. This language can be drawn from any sources, whether natural, technical, or artificial in character and interpretation. In the application to dynamic systems we tend to use the letters {''x''<sub>1</sub>, …, ''x''<sub>''n''</sub>} as our coordinate propositions, and to interpret them as denoting properties of a system's ''state'', that is, as propositions about its location in configuration space. Because I have to consider non-deterministic systems from the outset, I often use the word ''state'' in a loose sense, to denote the position or configuration component of a contemplated state vector, whether or not it ever gets a deterministic completion.
===Qualitative Logic and Quantitative Analogy===
===Qualitative Logic and Quantitative Analogy===
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''Logical'', however, is used in a third sense, which is at once more vital and more practical; to denote, namely, the systematic care, negative and positive, taken to safeguard reflection so that it may yield the best results under the given conditions.
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| align="right" colspan="3" | — John Dewey, ''How We Think'', [Dew, 56]
|}
These concepts and notations can now be explained in greater detail. In order to begin as simply as possible, I distinguish two levels of analysis and set out initially on the easier path. On the first level of analysis, I take spaces like '''B''', '''B'''<sup>''n''</sup>, and ('''B'''<sup>''n''</sup> → '''B''') at face value and treat them as the primary objects of interest. On the second level of analysis, I use these spaces as coordinate charts for talking about points and functions in more fundamental spaces.
These concepts and notations can now be explained in greater detail. In order to begin as simply as possible, I distinguish two levels of analysis and set out initially on the easier path. On the first level of analysis, I take spaces like '''B''', '''B'''<sup>''n''</sup>, and ('''B'''<sup>''n''</sup> → '''B''') at face value and treat them as the primary objects of interest. On the second level of analysis, I use these spaces as coordinate charts for talking about points and functions in more fundamental spaces.
===Philosophy of Notation : Formal Terms and Flexible Types===
===Philosophy of Notation : Formal Terms and Flexible Types===
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Where number is irrelevant, regimented mathematical technique has hitherto tended to be lacking. Thus it is that the progress of natural science has depended so largely upon the discernment of measurable quantity of one sort or another.
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| align="right" colspan="3" | — W.V. Quine, ''Mathematical Logic'', [Qui, 7]
|}
For much of our discussion propositions and boolean functions are treated as the same formal objects, or as different interpretations of the same formal calculus. This rule of interpretation has exceptions, though. There is a distinctively logical interest in the use of propositional calculus that is not exhausted by its functional interpretation. It is part of our task in this study to deal with these uniquely logical characteristics as they present themselves both in our subject matter and in our formal calculus. Just to provide a hint of what's at stake: In logic, as opposed to the more imaginative realms of mathematics, we consider it a good thing to always know what we are talking about. Where mathematics encourages tolerance for uninterpreted symbols as intermediate terms, logic exerts a keener effort to interpret directly each oblique carrier of meaning, no matter how slight, and to unfold the complicities of every indirection in the flow of information. Translated into functional terms, this means that we want to maintain a continual, immediate, and persistent sense of both the converse relation ''f''<sup>–1</sup> ⊆ '''B''' × '''B'''<sup>''n''</sup>, or what is the same thing, ''f''<sup>–1</sup> : '''B''' → ''Pow''('''B'''<sup>''n''</sup>), and the ''fibers'' or inverse images ''f''<sup>–1</sup>(0) and ''f''<sup>–1</sup>(1), associated with each boolean function ''f'' : '''B'''<sup>''n''</sup> → '''B''' that we use. In practical terms, the desired implementation of a propositional interpreter should incorporate our intuitive recognition that the induced partition of the functional domain into level sets ''f''<sup>–1</sup>(''b''), for ''b'' ∈ '''B''', is part and parcel of understanding the denotative uses of each propositional function ''f''.
For much of our discussion propositions and boolean functions are treated as the same formal objects, or as different interpretations of the same formal calculus. This rule of interpretation has exceptions, though. There is a distinctively logical interest in the use of propositional calculus that is not exhausted by its functional interpretation. It is part of our task in this study to deal with these uniquely logical characteristics as they present themselves both in our subject matter and in our formal calculus. Just to provide a hint of what's at stake: In logic, as opposed to the more imaginative realms of mathematics, we consider it a good thing to always know what we are talking about. Where mathematics encourages tolerance for uninterpreted symbols as intermediate terms, logic exerts a keener effort to interpret directly each oblique carrier of meaning, no matter how slight, and to unfold the complicities of every indirection in the flow of information. Translated into functional terms, this means that we want to maintain a continual, immediate, and persistent sense of both the converse relation ''f''<sup>–1</sup> ⊆ '''B''' × '''B'''<sup>''n''</sup>, or what is the same thing, ''f''<sup>–1</sup> : '''B''' → ''Pow''('''B'''<sup>''n''</sup>), and the ''fibers'' or inverse images ''f''<sup>–1</sup>(0) and ''f''<sup>–1</sup>(1), associated with each boolean function ''f'' : '''B'''<sup>''n''</sup> → '''B''' that we use. In practical terms, the desired implementation of a propositional interpreter should incorporate our intuitive recognition that the induced partition of the functional domain into level sets ''f''<sup>–1</sup>(''b''), for ''b'' ∈ '''B''', is part and parcel of understanding the denotative uses of each propositional function ''f''.
===The Analogy Between Real and Boolean Types===
===The Analogy Between Real and Boolean Types===
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Measurement consists in correlating our subject matter with the series of real numbers; and such correlations are desirable because, once they are set up, all the well-worked theory of numerical mathematics lies ready at hand as a tool for our further reasoning.
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| align="right" colspan="3" | — W.V. Quine, ''Mathematical Logic'', [Qui, 7]
|}
There are two further reasons why I am spending so much time on a careful treatment of types, and they both have to do with our being able to take full computational advantage of certain dimensions of flexibility in the types that apply to terms. First, the domains of differential geometry and logic programming are connected by analogies between real and boolean types of the same pattern. Second, the types involved in these patterns have important isomorphisms connecting them that apply on both the real and the boolean sides of the picture.
There are two further reasons why I am spending so much time on a careful treatment of types, and they both have to do with our being able to take full computational advantage of certain dimensions of flexibility in the types that apply to terms. First, the domains of differential geometry and logic programming are connected by analogies between real and boolean types of the same pattern. Second, the types involved in these patterns have important isomorphisms connecting them that apply on both the real and the boolean sides of the picture.
===Theory of Control and Control of Theory===
===Theory of Control and Control of Theory===
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You will hardly know who I am or what I mean,<br>
But I shall be good health to you nevertheless,<br>
But I shall be good health to you nevertheless,<br>
And filter and fibre your blood.</p>
And filter and fibre your blood.
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| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 88]
|}
In the boolean context, a function ''f'' : ''X'' → '''B''' is tantamount to a ''proposition'' about elements of ''X'', and the elements of ''X'' constitute the ''interpretations'' of that proposition. The fiber ''f''<sup>–1</sup>(1) comprises the set of ''models'' of ''f'', or examples of elements in ''X'' satisfying the proposition ''f''. The fiber ''f''<sup>–1</sup>(0) collects the complementary set of ''anti-models'', or the exceptions to the proposition ''f'' that exist in ''X''. Of course, the space of functions (''X'' → '''B''') is isomorphic to the set of all subsets of X, called the ''power set'' of ''X'' and often denoted as <font face="lucida calligraphy">Pow</font>(''X'') or 2<sup>''X''</sup>.
In the boolean context, a function ''f'' : ''X'' → '''B''' is tantamount to a ''proposition'' about elements of ''X'', and the elements of ''X'' constitute the ''interpretations'' of that proposition. The fiber ''f''<sup>–1</sup>(1) comprises the set of ''models'' of ''f'', or examples of elements in ''X'' satisfying the proposition ''f''. The fiber ''f''<sup>–1</sup>(0) collects the complementary set of ''anti-models'', or the exceptions to the proposition ''f'' that exist in ''X''. Of course, the space of functions (''X'' → '''B''') is isomorphic to the set of all subsets of X, called the ''power set'' of ''X'' and often denoted as <font face="lucida calligraphy">Pow</font>(''X'') or 2<sup>''X''</sup>.
===Reality at the Threshold of Logic===
===Reality at the Threshold of Logic===
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But no science can rest entirely on measurement, and many scientific investigations are quite out of reach of that device. To the scientist longing for non-quantitative techniques, then, mathematical logic brings hope.
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| align="right" colspan="3" | — W.V. Quine, ''Mathematical Logic'', [Qui, 7]
|}
Table 5 accumulates an array of notation that I hope will not be too distracting. Some of it is rarely needed, but has been filled in for the sake of completeness. Its purpose is simple, to give literal expression to the visual intuitions that come with venn diagrams, and to help build a bridge between our qualitative and quantitative outlooks on dynamic systems.
Table 5 accumulates an array of notation that I hope will not be too distracting. Some of it is rarely needed, but has been filled in for the sake of completeness. Its purpose is simple, to give literal expression to the visual intuitions that come with venn diagrams, and to help build a bridge between our qualitative and quantitative outlooks on dynamic systems.
===Tables of Propositional Forms===
===Tables of Propositional Forms===
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To the scientist longing for non-quantitative techniques, then, mathematical logic brings hope. It provides explicit techniques for manipulating the most basic ingredients of discourse.
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| align="right" colspan="3" | — W.V. Quine, ''Mathematical Logic'', [Qui, 7–8]
|}
To prepare for the next phase of discussion, Tables 6 and 7 collect and summarize all of the propositional forms on one and two variables. These propositional forms are represented over bases of boolean variables as complete sets of boolean-valued functions. Adjacent to their names and specifications are listed what are roughly the simplest expressions in the ''[[cactus language]]'', the particular syntax for propositional calculus that I use in formal and computational contexts. For the sake of orientation, the English paraphrases and the more common notations are listed in the last two columns. As simple and circumscribed as these low-dimensional universes may appear to be, a careful exploration of their differential extensions will involve us in complexities sufficient to demand our attention for some time to come.
To prepare for the next phase of discussion, Tables 6 and 7 collect and summarize all of the propositional forms on one and two variables. These propositional forms are represented over bases of boolean variables as complete sets of boolean-valued functions. Adjacent to their names and specifications are listed what are roughly the simplest expressions in the ''[[cactus language]]'', the particular syntax for propositional calculus that I use in formal and computational contexts. For the sake of orientation, the English paraphrases and the more common notations are listed in the last two columns. As simple and circumscribed as these low-dimensional universes may appear to be, a careful exploration of their differential extensions will involve us in complexities sufficient to demand our attention for some time to come.
==A Differential Extension of Propositional Calculus==
==A Differential Extension of Propositional Calculus==
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Fire over water:<br>
The image of the condition before transition.<br>
The image of the condition before transition.<br>
Thus the superior man is careful<br>
Thus the superior man is careful<br>
In the differentiation of things,<br>
In the differentiation of things,<br>
So that each finds its place.</p>
So that each finds its place.
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| align="right" | — ''I Ching'', Hexagram 64, [Wil, 249]
|}
This much preparation is enough to begin introducing my subject, if I excuse myself from giving full arguments for my definitional choices until some later stage. I am trying to develop a ''differential theory of qualitative equations'' that parallels the application of differential geometry to dynamic systems. The idea of a tangent vector is key to this work and a major goal is to find the right logical analogues of tangent spaces, bundles, and functors. The strategy is taken of looking for the simplest versions of these constructions that can be discovered within the realm of propositional calculus, so long as they serve to fill out the general theme.
This much preparation is enough to begin introducing my subject, if I excuse myself from giving full arguments for my definitional choices until some later stage. I am trying to develop a ''differential theory of qualitative equations'' that parallels the application of differential geometry to dynamic systems. The idea of a tangent vector is key to this work and a major goal is to find the right logical analogues of tangent spaces, bundles, and functors. The strategy is taken of looking for the simplest versions of these constructions that can be discovered within the realm of propositional calculus, so long as they serve to fill out the general theme.
===An Interlude on the Path===
===An Interlude on the Path===
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instead, speech would proceed from me,<br>
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while I stood in its path - a slender gap -<br>
There would have been no beginnings: instead, speech would proceed from me, while I stood in its path – a slender gap – the point of its possible disappearance.
the point of its possible disappearance.</p>
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| align="right" colspan="3" | — Michel Foucault, ''The Discourse on Language'', [Fou, 215]
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It may help to get a sense of the relation between '''B''' and '''D''' by considering the ''path classifier'' (or equivalence class of curves) approach to tangent vectors. As if by reflex, the thought of physical motion makes us cross over to a universe marked by the nominal character [<font face="lucida calligraphy">X</font>]. Given the boolean value system, a path in the space ''X'' = 〈<font face="lucida calligraphy">X</font>〉 is a map ''q'' : '''B''' → ''X''. In this case, the set of paths ('''B''' → ''X'') is isomorphic to the cartesian square ''X''<sup>2</sup> = ''X'' × ''X'', or the set of ordered pairs from ''X''.
It may help to get a sense of the relation between '''B''' and '''D''' by considering the ''path classifier'' (or equivalence class of curves) approach to tangent vectors. As if by reflex, the thought of physical motion makes us cross over to a universe marked by the nominal character [<font face="lucida calligraphy">X</font>]. Given the boolean value system, a path in the space ''X'' = 〈<font face="lucida calligraphy">X</font>〉 is a map ''q'' : '''B''' → ''X''. In this case, the set of paths ('''B''' → ''X'') is isomorphic to the cartesian square ''X''<sup>2</sup> = ''X'' × ''X'', or the set of ordered pairs from ''X''.
===The Extended Universe of Discourse===
===The Extended Universe of Discourse===
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At the moment of speaking, I would like to have perceived a nameless voice, long preceding me, leaving me merely to enmesh myself in it, taking up its cadence, and to lodge myself, when no one was looking, in its interstices as if it had paused an instant, in suspense, to beckon to me.
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| align="right" colspan="3" | — Michel Foucault, ''The Discourse on Language'', [Fou, 215]
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Next, we define the so-called ''extended alphabet'' or ''bundled alphabet'' E<font face="lucida calligraphy">A</font> as:
Next, we define the so-called ''extended alphabet'' or ''bundled alphabet'' E<font face="lucida calligraphy">A</font> as:
===Intentional Propositions===
===Intentional Propositions===
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Do you guess I have some intricate purpose?<br>
Well I have . . . . for the April rain has, and the mica on<br>
Well I have . . . . for the April rain has, and the mica on<br>
the side of a rock has.</p>
the side of a rock has.
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| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 45]
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In order to analyze the behavior of a system at successive moments in time, while staying within the limitations of propositional logic, it is necessary to create independent alphabets of logical features for each moment of time that we contemplate using in our discussion. These moments have reference to typical instances and relative intervals, not actual or absolute times. For example, to discuss ''velocities'' (first order rates of change) we need
In order to analyze the behavior of a system at successive moments in time, while staying within the limitations of propositional logic, it is necessary to create independent alphabets of logical features for each moment of time that we contemplate using in our discussion. These moments have reference to typical instances and relative intervals, not actual or absolute times. For example, to discuss ''velocities'' (first order rates of change) we need
===Life on Easy Street===
===Life on Easy Street===
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Failing to fetch me at first keep encouraged,<br>
Missing me one place search another,<br>
Missing me one place search another,<br>
I stop some where waiting for you</p>
I stop some where waiting for you
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| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 88]
|}
The finite character of the extended universe [E<font face="lucida calligraphy">A</font>] makes the problem of solving differential propositions relatively straightforward, at least,
The finite character of the extended universe [E<font face="lucida calligraphy">A</font>] makes the problem of solving differential propositions relatively straightforward, at least,
In view of these constraints and contingencies, my focus shifts to the tasks of approximation and interpretation that support intuition, especially in dealing with the natural kinds of differential propositions that arise in applications, and in the effort to understand, in succinct and adaptive forms, their dynamic implications. In the absence of direct insights, these tasks are partially carried out by forging analogies with the familiar situations and customary routines of ordinary calculus. But the indirect approach, going by way of specious analogy and intuitive habit, forces us to remain on guard against the circumstance that occurs when the word ''forging'' takes on its shadier nuance, indicting the constant risk of a counterfeit in the proportion.
In view of these constraints and contingencies, my focus shifts to the tasks of approximation and interpretation that support intuition, especially in dealing with the natural kinds of differential propositions that arise in applications, and in the effort to understand, in succinct and adaptive forms, their dynamic implications. In the absence of direct insights, these tasks are partially carried out by forging analogies with the familiar situations and customary routines of ordinary calculus. But the indirect approach, going by way of specious analogy and intuitive habit, forces us to remain on guard against the circumstance that occurs when the word ''forging'' takes on its shadier nuance, indicting the constant risk of a counterfeit in the proportion.
==Back to the Beginning : Some Exemplary Universes==
==Back to the Beginning : Exemplary Universes==
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borne way beyond all possible beginnings.</p>
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I would have preferred to be enveloped in words, borne way beyond all possible beginnings.
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| align="right" colspan="3" | — Michel Foucault, ''The Discourse on Language'', [Fou, 215]
|}
To anchor our understanding of differential logic, let us look at how the various concepts apply in the simplest possible concrete cases, where the initial dimension is only 1 or 2. In spite of the obvious simplicity of these cases, it is possible to observe how central difficulties of the subject begin to arise already at this stage.
To anchor our understanding of differential logic, let us look at how the various concepts apply in the simplest possible concrete cases, where the initial dimension is only 1 or 2. In spite of the obvious simplicity of these cases, it is possible to observe how central difficulties of the subject begin to arise already at this stage.
===A One-Dimensional Universe===
===A One-Dimensional Universe===
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There was never any more inception than there is now,<br>
Nor any more youth or age than there is now;<br>
Nor any more youth or age than there is now;<br>
And will never be any more perfection than there is now,<br>
And will never be any more perfection than there is now,<br>
Nor any more heaven or hell than there is now.</p>
Nor any more heaven or hell than there is now.
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| align="right" | — Walt Whitman, Leaves of Grass, [Whi, 28]
|}
Let <font face="lucida calligraphy">X</font> = {''x''<sub>1</sub>} = {''A''} be an alphabet that represents one boolean variable or a single logical feature. In this example I am using the capital letter "''A''" in a more usual informal way, to name a feature and not a space, at variance with my formerly stated formal conventions. At any rate, the basis element
Let <font face="lucida calligraphy">X</font> = {''x''<sub>1</sub>} = {''A''} be an alphabet that represents one boolean variable or a single logical feature. In this example I am using the capital letter "''A''" in a more usual informal way, to name a feature and not a space, at variance with my formerly stated formal conventions. At any rate, the basis element
It might be thought that we need to bring in an independent time variable at this point, but an insight of fundamental importance appears to be that the idea of process is more basic than the notion of time. A time variable is actually a reference to a ''clock'', that is, a canonical or a convenient process that is established or accepted as a standard of measurement, but in essence no different than any other process. This raises the question of how different subsystems in a more global process can be brought into comparison, and what it means for one process to serve the function of a local standard for others. But these inquiries only wrap up puzzles in further riddles, and are obviously too involved to be handled at our current level of approximation.
It might be thought that we need to bring in an independent time variable at this point, but an insight of fundamental importance appears to be that the idea of process is more basic than the notion of time. A time variable is actually a reference to a ''clock'', that is, a canonical or a convenient process that is established or accepted as a standard of measurement, but in essence no different than any other process. This raises the question of how different subsystems in a more global process can be brought into comparison, and what it means for one process to serve the function of a local standard for others. But these inquiries only wrap up puzzles in further riddles, and are obviously too involved to be handled at our current level of approximation.
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eternity indicate?</p>
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The clock indicates the moment . . . . but what does<br>
eternity indicate?
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| align="right" | — Walt Whitman, 'Leaves of Grass', [Whi, 79]
|}
Observe that the secular inference rules, used by themselves, involve a loss of information, since nothing in them can tell us whether the momenta {(d''A''), d''A''} are preserved or changed in the next instance. In order to know this, we would have to determine d<sup>2</sup>''A'', and so on, pursuing an infinite regress. Ultimately, in order to rest with a finitely determinate system, it is necessary to make an infinite assumption, for example, that d<sup>''k''</sup>''A'' = 0 for all ''k'' greater than some fixed value ''M''. Another way to escape the regress is through the provision of a dynamic law, in typical form making higher order differentials dependent on lower degrees and estates.
Observe that the secular inference rules, used by themselves, involve a loss of information, since nothing in them can tell us whether the momenta {(d''A''), d''A''} are preserved or changed in the next instance. In order to know this, we would have to determine d<sup>2</sup>''A'', and so on, pursuing an infinite regress. Ultimately, in order to rest with a finitely determinate system, it is necessary to make an infinite assumption, for example, that d<sup>''k''</sup>''A'' = 0 for all ''k'' greater than some fixed value ''M''. Another way to escape the regress is through the provision of a dynamic law, in typical form making higher order differentials dependent on lower degrees and estates.
===Example 1. A Square Rigging===
===Example 1. A Square Rigging===
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Always the procreant urge of the world.</p>
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Urge and urge and urge,<br>
Always the procreant urge of the world.
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| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 28]
|}
By way of example, suppose that we are given the initial condition ''A'' = d''A'' and the law d<sup>2</sup>''A'' = (''A''). Then, since "''A'' = d''A''" ⇔ "''A'' d''A'' or (''A'')(d''A'')", we may infer two possible trajectories, as displayed in Table 11. In either of these cases, the state ''A''(d''A'')(d<sup>2</sup>''A'') is a stable attractor or a terminal condition for both starting points.
By way of example, suppose that we are given the initial condition ''A'' = d''A'' and the law d<sup>2</sup>''A'' = (''A''). Then, since "''A'' = d''A''" ⇔ "''A'' d''A'' or (''A'')(d''A'')", we may infer two possible trajectories, as displayed in Table 11. In either of these cases, the state ''A''(d''A'')(d<sup>2</sup>''A'') is a stable attractor or a terminal condition for both starting points.
===Back to the Feature===
===Back to the Feature===
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green stuff woven.</p>
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I guess it must be the flag of my disposition, out of hopeful<br>
green stuff woven.
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| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 31]
|}
Let us assume that the sense intended for differential features is well enough established in the intuition, for now, that I may continue with outlining the structure of the differential extension [E<font face="lucida calligraphy">X</font>] = [''A'', d''A'']. Over the extended alphabet E<font face="lucida calligraphy">X</font> = {''x''<sub>1</sub>, d''x''<sub>1</sub>} = {''A'', d''A''}, of cardinality 2<sup>''n''</sup> = 2, we generate the set of points, E''X'', of cardinality 2<sup>2''n''</sup> = 4, that bears the following chain of equivalent descriptions:
Let us assume that the sense intended for differential features is well enough established in the intuition, for now, that I may continue with outlining the structure of the differential extension [E<font face="lucida calligraphy">X</font>] = [''A'', d''A'']. Over the extended alphabet E<font face="lucida calligraphy">X</font> = {''x''<sub>1</sub>, d''x''<sub>1</sub>} = {''A'', d''A''}, of cardinality 2<sup>''n''</sup> = 2, we generate the set of points, E''X'', of cardinality 2<sup>2''n''</sup> = 4, that bears the following chain of equivalent descriptions:
===Tacit Extensions===
===Tacit Extensions===
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I would really like to have slipped imperceptibly into this lecture, as into all the others I shall be delivering, perhaps over the years ahead.
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|-
| align="right" colspan="3" | — Michel Foucault, ''The Discourse on Language'', [Fou, 215]
|}
Strictly speaking, however, there is a subtle distinction in type between the function ''f''<sub>''i''</sub> : ''X'' → '''B''' and the corresponding function ''g''<sub>''j''</sub> : E''X'' → '''B''', even though they share the same logical expression. Being human, we insist on preserving all the aesthetic delights afforded by the abstractly unified form of the "cake" while giving up none of the diverse contents that its substantive consummation can provide. In short, we want to maintain the logical equivalence of expressions that represent the same proposition, while appreciating the full diversity of that proposition's functional and typical representatives. Both perspectives, and all the levels of abstraction extending through them, have their reasons, as will develop in time.
Strictly speaking, however, there is a subtle distinction in type between the function ''f''<sub>''i''</sub> : ''X'' → '''B''' and the corresponding function ''g''<sub>''j''</sub> : E''X'' → '''B''', even though they share the same logical expression. Being human, we insist on preserving all the aesthetic delights afforded by the abstractly unified form of the "cake" while giving up none of the diverse contents that its substantive consummation can provide. In short, we want to maintain the logical equivalence of expressions that represent the same proposition, while appreciating the full diversity of that proposition's functional and typical representatives. Both perspectives, and all the levels of abstraction extending through them, have their reasons, as will develop in time.
===Example 2. Drives and Their Vicissitudes===
===Example 2. Drives and Their Vicissitudes===
{| width="100%" cellpadding="0" cellspacing="0"
| width="40%" |
| width="60%" |
I open my scuttle at night and see the far-sprinkled systems,<br>
And all I see, multiplied as high as I can cipher, edge but<br>
And all I see, multiplied as high as I can cipher, edge but<br>
the rim of the farther systems.</p>
the rim of the farther systems.
|-
|
| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 81]
|}
Before we leave the one-feature case let's look at a more substantial example, one that illustrates a general class of curves that can be charted through the extended feature spaces and that provides an opportunity to discuss a number of important themes concerning their structure and dynamics.
Before we leave the one-feature case let's look at a more substantial example, one that illustrates a general class of curves that can be charted through the extended feature spaces and that provides an opportunity to discuss a number of important themes concerning their structure and dynamics.
==Transformations of Discourse==
==Transformations of Discourse==
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It is understandable that an engineer should be completely absorbed in his speciality, instead of pouring himself out into the freedom and vastness of the world of thought, even though his machines are being sent off to the ends of the earth; for he no more needs to be capable of applying to his own personal soul what is daring and new in the soul of his subject than a machine is in fact capable of applying to itself the differential calculus on which it is based. The same thing cannot, however, be said about mathematics; for here we have the new method of thought, pure intellect, the very well-spring of the times, the ''fons et origo'' of an unfathomable transformation.
| width="4%" |
|-
| align="right" colspan="3" | — Robert Musil, ''The Man Without Qualities'', [Mus, 39]
|}
In this section we take up the general study of logical transformations, or maps that relate one universe of discourse to another. In many ways, and especially as applied to the subject of intelligent dynamic systems, my argument develops the antithesis of the statement just quoted. Along the way, if incidental to my ends, I hope this essay can pose a fittingly irenic epitaph to the frankly ironic epigraph inscribed at its head.
In this section we take up the general study of logical transformations, or maps that relate one universe of discourse to another. In many ways, and especially as applied to the subject of intelligent dynamic systems, my argument develops the antithesis of the statement just quoted. Along the way, if incidental to my ends, I hope this essay can pose a fittingly irenic epitaph to the frankly ironic epigraph inscribed at its head.
===Foreshadowing Transformations : Extensions and Projections of Discourse===
===Foreshadowing Transformations : Extensions and Projections of Discourse===
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And, despite the care which she took to look behind her at every moment, she failed to see a shadow which followed her like her own shadow, which stopped when she stopped, which started again when she did, and which made no more noise than a well-conducted shadow should.
| width="4%" |
|-
| align="right" colspan="3" | — Gaston Leroux, ''The Phantom of the Opera'', [Ler, 126]
|}
Many times in our discussion we have occasion to place one universe of discourse in the context of a larger universe of discourse. An embedding of the general type [<font face="lucida calligraphy">X</font>] → [<font face="lucida calligraphy">Y</font>] is implied any time that we make use of one alphabet <font face="lucida calligraphy">X</font> that happens to be included in another alphabet <font face="lucida calligraphy">Y</font>. When we are discussing differential issues we usually have in mind that the extended alphabet <font face="lucida calligraphy">Y</font> has a special construction or a specific lexical relation with respect to the initial alphabet <font face="lucida calligraphy">X</font>, one that is marked by characteristic types of accents, indices, or inflected forms.
Many times in our discussion we have occasion to place one universe of discourse in the context of a larger universe of discourse. An embedding of the general type [<font face="lucida calligraphy">X</font>] → [<font face="lucida calligraphy">Y</font>] is implied any time that we make use of one alphabet <font face="lucida calligraphy">X</font> that happens to be included in another alphabet <font face="lucida calligraphy">Y</font>. When we are discussing differential issues we usually have in mind that the extended alphabet <font face="lucida calligraphy">Y</font> has a special construction or a specific lexical relation with respect to the initial alphabet <font face="lucida calligraphy">X</font>, one that is marked by characteristic types of accents, indices, or inflected forms.
===Thematization of Functions : And a Declaration of Independence for Variables===
===Thematization of Functions : And a Declaration of Independence for Variables===
{| width="100%"
| align="left" |
The forms of things unknown, the poet's pen<br>
''And as imagination bodies forth''<br>
Turns them to shapes, and gives to airy nothing<br>
''The forms of things unknown, the poet's pen''<br>
A local habitation and a name.</p>
''Turns them to shapes, and gives to airy nothing''<br>
''A local habitation and a name.''
| align="right" valign="bottom" | A Midsummer Night's Dream, 5.1.18
|}
In the representation of propositions as functions it is possible to notice different degrees of explicitness in the way their functional character is symbolized. To indicate what I mean by this, the next series of Figures illustrates a set of graphic conventions that will be put to frequent use in the remainder of this discussion, both to mark the relevant distinctions and to help us convert between related expressions at different levels of explicitness in their functionality.
In the representation of propositions as functions it is possible to notice different degrees of explicitness in the way their functional character is symbolized. To indicate what I mean by this, the next series of Figures illustrates a set of graphic conventions that will be put to frequent use in the remainder of this discussion, both to mark the relevant distinctions and to help us convert between related expressions at different levels of explicitness in their functionality.
====Thematization : Venn Diagrams====
====Thematization : Venn Diagrams====
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He consumes an eternal passion and is indifferent which chance happens<br>
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and which possible contingency of fortune or misfortune and persuades<br>
The known universe has one complete lover and that is the greatest poet. He consumes an eternal passion and is indifferent which chance happens and which possible contingency of fortune or misfortune and persuades daily and hourly his delicious pay.
daily and hourly his delicious pay.</p>
| width="4%" |
|-
| align="right" colspan="3" | — Walt Whitman, ''Leaves of Grass'', [Whi, 11–12]
|}
Figure 20-i traces the first couple of steps in this order of ''thematic'' progression, that will gradually run the gamut through a complete series of degrees of functional explicitness in the expression of logical propositions. The first venn diagram represents a situation where the function is indicated by a shaded figure and a logical expression. At this stage one may be thinking of the proposition only as expressed by a formula in a particular language and its content only as a subset of the universe of discourse, as when one considers the proposition ''u''<b>·</b>''v'' in [''u'', ''v''].
Figure 20-i traces the first couple of steps in this order of ''thematic'' progression, that will gradually run the gamut through a complete series of degrees of functional explicitness in the expression of logical propositions. The first venn diagram represents a situation where the function is indicated by a shaded figure and a logical expression. At this stage one may be thinking of the proposition only as expressed by a formula in a particular language and its content only as a subset of the universe of discourse, as when one considers the proposition ''u''<b>·</b>''v'' in [''u'', ''v''].
====Thematization : Truth Tables====
====Thematization : Truth Tables====
{| width="100%" cellpadding="0" cellspacing="0"
| width="4%" |
beings or places or contingencies is a nuisance and a revolt.</p>
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That which distorts honest shapes or which creates unearthly beings or places or contingencies is a nuisance and a revolt.
| width="4%" |
|-
| align="right" colspan="3" | — Walt Whitman, ''Leaves of Grass'', [Whi, 19]
|}
Tables 22 through 25 outline a method for computing the thematic extensions of propositions in terms of their coordinate values.
Tables 22 through 25 outline a method for computing the thematic extensions of propositions in terms of their coordinate values.
===Propositional Transformations===
===Propositional Transformations===
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| width="4%" |
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If only the word 'artificial' were associated with the idea of ''art'', or expert skill gained through voluntary apprenticeship (instead of suggesting the factitious and unreal), we might say that ''logical'' refers to artificial thought.
| width="4%" |
|-
| align="right" colspan="3" | — John Dewey, ''How We Think'', [Dew, 56–57]
|}
In this Subdivision I develop a comprehensive set of concepts for dealing with transformations between universes of discourse. In this most general context the source and the target universes of a transformation are allowed to be distinct, but may also be one and the same. When these concepts are applied to dynamic systems one focuses on the important special cases of transformations that map a universe into itself, and transformations of this shape may be interpreted as the state transitions of a discrete dynamical process, as these take place among the myriad ways that a universe of discourse might change, and by that change turn into itself.
In this Subdivision I develop a comprehensive set of concepts for dealing with transformations between universes of discourse. In this most general context the source and the target universes of a transformation are allowed to be distinct, but may also be one and the same. When these concepts are applied to dynamic systems one focuses on the important special cases of transformations that map a universe into itself, and transformations of this shape may be interpreted as the state transitions of a discrete dynamical process, as these take place among the myriad ways that a universe of discourse might change, and by that change turn into itself.
====Transformations of General Type====
====Transformations of General Type====
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| width="4%" |
| width="92%" |
''Es ist passiert'', "it just sort of happened", people said there when other people in other places thought heaven knows what had occurred. It was a peculiar phrase, not known in this sense to the Germans and with no equivalent in other languages, the very breath of it transforming facts and the bludgeonings of fate into something light as eiderdown, as thought itself.
| width="4%" |
|-
| align="right" colspan="3" | — Robert Musil, ''The Man Without Qualities'', [Mus, 34]
|}
Consider the situation illustrated in Figure 30, where the alphabets <font face="lucida calligraphy">U</font> = {''u'', ''v''} and <font face="lucida calligraphy">X</font> = {''x'', ''y'', ''z''} are used to label basic features in two different logical universes, ''U''<sup> •</sup> = [''u'', ''v''] and ''X''<sup> •</sup> = [''x'', ''y'', ''z''].
Consider the situation illustrated in Figure 30, where the alphabets <font face="lucida calligraphy">U</font> = {''u'', ''v''} and <font face="lucida calligraphy">X</font> = {''x'', ''y'', ''z''} are used to label basic features in two different logical universes, ''U''<sup> •</sup> = [''u'', ''v''] and ''X''<sup> •</sup> = [''x'', ''y'', ''z''].
===Analytic Expansions : Operators and Functors===
===Analytic Expansions : Operators and Functors===
{| width="100%" cellpadding="0" cellspacing="0"
| width="4%" |
have practical bearings you ''conceive'' the<br>
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objects of your ''conception'' to have. Then,<br>
Consider what effects that might ''conceivably'' have practical bearings you ''conceive'' the objects of your ''conception'' to have. Then, your ''conception'' of those effects is the whole of your ''conception'' of the object.
your ''conception'' of those effects is the<br>
| width="4%" |
whole of your ''conception'' of the object.</p>
|-
| align="right" colspan="3" | — C.S. Peirce, "The Maxim of Pragmatism", CP 5.438
|}
Given the barest idea of a logical transformation, as suggested by the sketch in Figure 30, and having conceptualized the universe of discourse, with all of its points and propositions, as a beginning object of discussion, we are ready to enter the next phase of our investigation.
Given the barest idea of a logical transformation, as suggested by the sketch in Figure 30, and having conceptualized the universe of discourse, with all of its points and propositions, as a beginning object of discussion, we are ready to enter the next phase of our investigation.
====Differential Analysis of Propositions and Transformations====
====Differential Analysis of Propositions and Transformations====
{| width="100%" cellpadding="0" cellspacing="0"
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he resultant metaphysical problem now is this: ''Does the man go round the squirrel or not?''
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|-
| align="right" colspan="3" | — William James, ''Pragmatism'', [Jam, 43]
|}
The approach to the differential analysis of logical propositions and transformations of discourse that will be pursued here is carried out in terms of particular operators <font face=georgia>'''W'''</font> that act on propositions ''F'' or on transformations ''F'' to yield the corresponding operator maps <font face=georgia>'''W'''</font>''F''. The operator results then become the subject of a series of further stages of analysis, which take them apart into their propositional components, rendering them as a set of purely logical constituents. After this is done, all the parts are then re-integrated to reconstruct the original object in the light of a more complete understanding, at least in ways that enable one to appreciate certain aspects of it with fresh insight.
The approach to the differential analysis of logical propositions and transformations of discourse that will be pursued here is carried out in terms of particular operators <font face=georgia>'''W'''</font> that act on propositions ''F'' or on transformations ''F'' to yield the corresponding operator maps <font face=georgia>'''W'''</font>''F''. The operator results then become the subject of a series of further stages of analysis, which take them apart into their propositional components, rendering them as a set of purely logical constituents. After this is done, all the parts are then re-integrated to reconstruct the original object in the light of a more complete understanding, at least in ways that enable one to appreciate certain aspects of it with fresh insight.
=====The Secant Operator : <font face=georgia>'''E'''</font>=====
=====The Secant Operator : <font face=georgia>'''E'''</font>=====
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Mr. Peirce, after pointing out that our beliefs are really rules for action, said that, to develop a thought's meaning, we need only determine what conduct it is fitted to produce: that conduct is for us its sole significance.
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|-
| align="right" colspan="3" | — William James, ''Pragmatism'', [Jam, 46]
|}
Figures 33-i and 33-ii depict two stages in the form of analysis that will be applied to transformations throughout the remainder of this study. From now on our interest is staked on an operator denoted "<font face=georgia>'''E'''</font>", which receives the principal investment of analytic attention, and on the constituent parts of <font face=georgia>'''E'''</font>, which derive their shares of significance as developed by the analysis. In the sequel, I refer to <font face=georgia>'''E'''</font> as the ''secant operator'', taking it for granted that a context has been chosen that defines its type. The secant operator has the component description <font face=georgia>'''E'''</font> = ‹<math>\epsilon</math>, E›, and its active ingredient E is known as the ''enlargement operator''. (Here, I have named E after the literal ancestor of the shift operator in the calculus of finite differences, defined so that E''f''(''x'') = ''f''(''x''+1) for any suitable function ''f'', though of course the logical analogue that we take up here must have a rather different definition.)
Figures 33-i and 33-ii depict two stages in the form of analysis that will be applied to transformations throughout the remainder of this study. From now on our interest is staked on an operator denoted "<font face=georgia>'''E'''</font>", which receives the principal investment of analytic attention, and on the constituent parts of <font face=georgia>'''E'''</font>, which derive their shares of significance as developed by the analysis. In the sequel, I refer to <font face=georgia>'''E'''</font> as the ''secant operator'', taking it for granted that a context has been chosen that defines its type. The secant operator has the component description <font face=georgia>'''E'''</font> = ‹<math>\epsilon</math>, E›, and its active ingredient E is known as the ''enlargement operator''. (Here, I have named E after the literal ancestor of the shift operator in the calculus of finite differences, defined so that E''f''(''x'') = ''f''(''x''+1) for any suitable function ''f'', though of course the logical analogue that we take up here must have a rather different definition.)
=====The Radius Operator : <font face=georgia>'''e'''</font>=====
=====The Radius Operator : <font face=georgia>'''e'''</font>=====
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And the tangible fact at the root of all our thought-distinctions, however subtle, is that there is no one of them so fine as to consist in anything but a possible difference of practice.
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|-
| align="right" colspan="3" | — William James, ''Pragmatism'', [Jam, 46]
|}
The operator identified as <font face=georgia>'''d'''</font><sup>0</sup> in the analytic diagram (Figure 33) has the sole purpose of creating a proxy for ''F'' in the appropriately extended context. Construed in terms of its broadest components, <font face=georgia>'''d'''</font><sup>0</sup> is equivalent to the doubly tacit extension operator ‹<math>\epsilon</math>, <math>\epsilon</math>›, in recognition of which let us redub it as "<font face=georgia>'''e'''</font>". Pursuing a geometric analogy, we may refer to <font face=georgia>'''e'''</font> = ‹<math>\epsilon</math>, <math>\epsilon</math>› = <font face=georgia>'''d'''</font><sup>0</sup> as the ''radius operator''. The operation that is intended by all of these forms is defined by the equation:
The operator identified as <font face=georgia>'''d'''</font><sup>0</sup> in the analytic diagram (Figure 33) has the sole purpose of creating a proxy for ''F'' in the appropriately extended context. Construed in terms of its broadest components, <font face=georgia>'''d'''</font><sup>0</sup> is equivalent to the doubly tacit extension operator ‹<math>\epsilon</math>, <math>\epsilon</math>›, in recognition of which let us redub it as "<font face=georgia>'''e'''</font>". Pursuing a geometric analogy, we may refer to <font face=georgia>'''e'''</font> = ‹<math>\epsilon</math>, <math>\epsilon</math>› = <font face=georgia>'''d'''</font><sup>0</sup> as the ''radius operator''. The operation that is intended by all of these forms is defined by the equation:
=====The Phantom of the Operators : '''η'''=====
=====The Phantom of the Operators : '''η'''=====
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I was wondering what the reason could be, when I myself raised my head and everything within me seemed drawn towards the Unseen, ''which was playing the most perfect music''!
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|-
| align="right" colspan="3" | — Gaston Leroux, ''The Phantom of the Opera'', [Ler, 81]
|}
I now describe an operator whose persistent but elusive action behind the scenes, whose slightly twisted and ambivalent character, and whose fugitive disposition, caught somewhere in flight between the arrantly negative and the positive but errant intent, has cost me some painstaking trouble to detect. In the end I shall place it among the other extensions and projections, as a shade among shadows, of muted tones and motley hue, that adumbrates its own thematic frame and paradoxically lights the way toward a whole new spectrum of values.
I now describe an operator whose persistent but elusive action behind the scenes, whose slightly twisted and ambivalent character, and whose fugitive disposition, caught somewhere in flight between the arrantly negative and the positive but errant intent, has cost me some painstaking trouble to detect. In the end I shall place it among the other extensions and projections, as a shade among shadows, of muted tones and motley hue, that adumbrates its own thematic frame and paradoxically lights the way toward a whole new spectrum of values.
=====The Chord Operator : <font face=georgia>'''D'''</font>=====
=====The Chord Operator : <font face=georgia>'''D'''</font>=====
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What difference would it practically make to any one if this notion rather than that notion were true? If no practical difference whatever can be traced, then the alternatives mean practically the same thing, and all dispute is idle.
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|-
| align="right" colspan="3" | — William James, ''Pragmatism'', [Jam, 45]
|}
Next I discuss an operator that is always immanent in this form of analysis, and remains implicitly present in the entire proceeding. It may appear once as a record: a relic or revenant that reprises the reminders of an earlier stage of development. Or it may appear always as a resource: a reserve or redoubt that caches in advance an echo of what remains to be played out, cleared up, and requited in full at a future stage. And all of this remains true whether or not we recall the key at any time, and whether or not the subtending theme is recited explicitly at any stage of play.
Next I discuss an operator that is always immanent in this form of analysis, and remains implicitly present in the entire proceeding. It may appear once as a record: a relic or revenant that reprises the reminders of an earlier stage of development. Or it may appear always as a resource: a reserve or redoubt that caches in advance an echo of what remains to be played out, cleared up, and requited in full at a future stage. And all of this remains true whether or not we recall the key at any time, and whether or not the subtending theme is recited explicitly at any stage of play.
=====The Tangent Operator : <font face=georgia>'''T'''</font>=====
=====The Tangent Operator : <font face=georgia>'''T'''</font>=====
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They take part in scenes of whose significance they have no inkling. They are merely tangent to curves of history the beginnings and ends and forms of which pass wholly beyond their ken. So we are tangent to the wider life of things.
| width="4%" |
|-
| align="right" colspan="3" | — William James, ''Pragmatism'', [Jam, 300]
|}
The operator tagged as <font face=georgia>'''d'''</font><sup>1</sup> in the analytic diagram (Figure 33) is called the ''tangent operator'', and is usually denoted in this text as <font face=georgia>'''d'''</font> or <font face=georgia>'''T'''</font>. Because it has the properties required to qualify as a functor, namely, preserving the identity element of the composition operation and the articulated form of every composure among transformations, it also earns the title of a ''tangent functor''. According to the custom adopted here, we dissect it as <font face=georgia>'''T'''</font> = <font face=georgia>'''d'''</font> = ‹<math>\epsilon</math>, d›, where d is the operator that yields the first order differential d''F'' when applied to a transformation ''F'', and whose name is legion.
The operator tagged as <font face=georgia>'''d'''</font><sup>1</sup> in the analytic diagram (Figure 33) is called the ''tangent operator'', and is usually denoted in this text as <font face=georgia>'''d'''</font> or <font face=georgia>'''T'''</font>. Because it has the properties required to qualify as a functor, namely, preserving the identity element of the composition operation and the articulated form of every composure among transformations, it also earns the title of a ''tangent functor''. According to the custom adopted here, we dissect it as <font face=georgia>'''T'''</font> = <font face=georgia>'''d'''</font> = ‹<math>\epsilon</math>, d›, where d is the operator that yields the first order differential d''F'' when applied to a transformation ''F'', and whose name is legion.
====Analytic Expansion of Conjunction====
====Analytic Expansion of Conjunction====
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<p>In her sufferings she read a great deal and discovered that she had lost something, the possession of which she had previously not been much aware of: a soul.</p>
<p>In her sufferings she read a great deal and discovered that she had lost something, the possession of which she had previously not been much aware of: a soul.</p>
<p>What is that? It is easily defined negatively: it is simply what curls up and hides when there is any mention of algebraic series.</p>
<p>What is that? It is easily defined negatively: it is simply what curls up and hides when there is any mention of algebraic series.</p>
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|-
| align="right" colspan="3" | — Robert Musil, ''The Man Without Qualities'', [Mus, 118]
|}
Figure 35 pictures the form of conjunction ''J'' : '''B'''<sup>2</sup> → '''B''' as a transformation from the 2-dimensional universe [''u'', ''v''] to the 1-dimensional universe [''x'']. This is a subtle but significant change of viewpoint on the proposition, attaching an arbitrary but concrete quality to its functional value. Using the language introduced earlier, we can express this change by saying that the proposition ''J'' : 〈''u'', ''v''〉 → '''B''' is being recast into the thematized role of a transformation ''J'' : [''u'', ''v''] → [''x''], where the new variable ''x'' takes the part of a thematic variable ¢(''J'').
Figure 35 pictures the form of conjunction ''J'' : '''B'''<sup>2</sup> → '''B''' as a transformation from the 2-dimensional universe [''u'', ''v''] to the 1-dimensional universe [''x'']. This is a subtle but significant change of viewpoint on the proposition, attaching an arbitrary but concrete quality to its functional value. Using the language introduced earlier, we can express this change by saying that the proposition ''J'' : 〈''u'', ''v''〉 → '''B''' is being recast into the thematized role of a transformation ''J'' : [''u'', ''v''] → [''x''], where the new variable ''x'' takes the part of a thematic variable ¢(''J'').
=====Tacit Extension of Conjunction=====
=====Tacit Extension of Conjunction=====
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| width="60%" |
I teach straying from me, yet who can stray from me?<br>
I follow you whoever you are from the present hour;<br>
I follow you whoever you are from the present hour;<br>
My words itch at your ears till you understand them.</p>
My words itch at your ears till you understand them.
|-
|
| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 83]
|}
Earlier I defined the tacit extension operators <math>\epsilon</math> : ''X''<sup> •</sup> → ''Y''<sup> •</sup> as maps embedding each proposition of a given universe ''X''<sup> •</sup> in a more generously given universe ''Y''<sup> •</sup> containing ''X''<sup> •</sup>. Of immediate interest are the tacit extensions <math>\epsilon</math> : ''U''<sup> •</sup> → E''U''<sup> •</sup>, that locate each proposition of ''U''<sup> •</sup> in the enlarged context of E''U''<sup> •</sup>. In its application to the propositional conjunction ''J'' = ''u'' ''v'' in [''u'', ''v''], the tacit extension operator <math>\epsilon</math> produces the proposition <math>\epsilon</math>''J'' in E''U''<sup> •</sup> = [''u'', ''v'', d''u'', d''v'']. The extended proposition <math>\epsilon</math>''J'' may be computed according to the scheme in Table 36, in effect, doing nothing more than conjoining a tautology of [d''u'', d''v''] to ''J'' in ''U''<sup> •</sup>.
Earlier I defined the tacit extension operators <math>\epsilon</math> : ''X''<sup> •</sup> → ''Y''<sup> •</sup> as maps embedding each proposition of a given universe ''X''<sup> •</sup> in a more generously given universe ''Y''<sup> •</sup> containing ''X''<sup> •</sup>. Of immediate interest are the tacit extensions <math>\epsilon</math> : ''U''<sup> •</sup> → E''U''<sup> •</sup>, that locate each proposition of ''U''<sup> •</sup> in the enlarged context of E''U''<sup> •</sup>. In its application to the propositional conjunction ''J'' = ''u'' ''v'' in [''u'', ''v''], the tacit extension operator <math>\epsilon</math> produces the proposition <math>\epsilon</math>''J'' in E''U''<sup> •</sup> = [''u'', ''v'', d''u'', d''v'']. The extended proposition <math>\epsilon</math>''J'' may be computed according to the scheme in Table 36, in effect, doing nothing more than conjoining a tautology of [d''u'', d''v''] to ''J'' in ''U''<sup> •</sup>.
=====Enlargement Map of Conjunction=====
=====Enlargement Map of Conjunction=====
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No one could have established the existence of any details that might not just as well have existed in earlier times too; but all the relations between things had shifted slightly. Ideas that had once been of lean account grew fat.
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|-
| align="right" colspan="3" | — Robert Musil, ''The Man Without Qualities'', [Mus, 62]
|}
The enlargement map E''J'' is computed from the proposition ''J'' by making a particular class of formal substitutions for its variables, in this case ''u'' + d''u'' for ''u'' and ''v'' + d''v'' for ''v'', and subsequently expanding the result in whatever way happens to be convenient for the end in view.
The enlargement map E''J'' is computed from the proposition ''J'' by making a particular class of formal substitutions for its variables, in this case ''u'' + d''u'' for ''u'' and ''v'' + d''v'' for ''v'', and subsequently expanding the result in whatever way happens to be convenient for the end in view.
=====Digression : Reflection on Use and Mention=====
=====Digression : Reflection on Use and Mention=====
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Reflection is turning a topic over in various aspects and in various lights so that nothing significant about it shall be overlooked — almost as one might turn a stone over to see what its hidden side is like or what is covered by it.
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|-
| align="right" colspan="3" | — John Dewey, ''How We Think'', [Dew, 57]
|}
The contrast drawn in logic between the ''use'' and the ''mention'' of a proposition corresponds to the difference that we observe in functional terms between using "''J'' " to indicate the region ''J''<sup>–1</sup>(1) and using "''J'' " to indicate the function ''J''. You may think that one of these uses ought to be proscribed, and logicians are quick to prescribe against their confusion. But there seems to be no likelihood in practice that their interactions can be avoided. If the name "''J'' " is used as a sign of the function ''J'', and if the function ''J'' has its use in signifying something else, as would constantly be the case when some future theory of signs has given a functional meaning to every sign whatsoever, then is not "''J'' " by transitivity a sign of the thing itself? There are, of course, two answers to this question. Not every act of signifying or referring need be transitive. Not every warrant or guarantee or certificate is automatically transferable, indeed, not many. Not every feature of a feature is a feature of the featuree. Otherwise we have an inference like the following: If a buffalo is white, and white is a color, then a buffalo is a color. But a buffalo is not, only buff is.
The contrast drawn in logic between the ''use'' and the ''mention'' of a proposition corresponds to the difference that we observe in functional terms between using "''J'' " to indicate the region ''J''<sup>–1</sup>(1) and using "''J'' " to indicate the function ''J''. You may think that one of these uses ought to be proscribed, and logicians are quick to prescribe against their confusion. But there seems to be no likelihood in practice that their interactions can be avoided. If the name "''J'' " is used as a sign of the function ''J'', and if the function ''J'' has its use in signifying something else, as would constantly be the case when some future theory of signs has given a functional meaning to every sign whatsoever, then is not "''J'' " by transitivity a sign of the thing itself? There are, of course, two answers to this question. Not every act of signifying or referring need be transitive. Not every warrant or guarantee or certificate is automatically transferable, indeed, not many. Not every feature of a feature is a feature of the featuree. Otherwise we have an inference like the following: If a buffalo is white, and white is a color, then a buffalo is a color. But a buffalo is not, only buff is.
The logical or pragmatic distinction between use and mention is cogent and necessary, and so is the analogous functional distinction between determining a value and determining what determines that value, but so are the normal techniques that we use to make these distinctions apply flexibly in practice. The way that the hue and cry about use and mention is raised in logical discussions, you might be led to think that this single dimension of choices embraces the only kinds of use worth mentioning and the only kinds of mention worth using. It will constitute the expeditionary and taxonomic tasks of that future theory of signs to explore and to classify the many other constellations and dimensions of use and mention that are yet to be opened up by the generative potential of full-fledged sign relations.
The logical or pragmatic distinction between use and mention is cogent and necessary, and so is the analogous functional distinction between determining a value and determining what determines that value, but so are the normal techniques that we use to make these distinctions apply flexibly in practice. The way that the hue and cry about use and mention is raised in logical discussions, you might be led to think that this single dimension of choices embraces the only kinds of use worth mentioning and the only kinds of mention worth using. It will constitute the expeditionary and taxonomic tasks of that future theory of signs to explore and to classify the many other constellations and dimensions of use and mention that are yet to be opened up by the generative potential of full-fledged sign relations.
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The well-known capacity that thoughts have — as doctors have discovered — for dissolving and dispersing those hard lumps of deep, ingrowing, morbidly entangled conflict that arise out of gloomy regions of the self probably rests on nothing other than their social and worldly nature, which links the individual being with other people and things; but unfortunately what gives them their power of healing seems to be the same as what diminishes the quality of personal experience in them.
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|-
| align="right" colspan="3" | — Robert Musil, ''The Man Without Qualities'', [Mus, 130]
|}
=====Difference Map of Conjunction=====
=====Difference Map of Conjunction=====
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"It doesn't matter what one does", the Man Without Qualities said to himself, shrugging his shoulders. "In a tangle of forces like this it doesn't make a scrap of difference." He turned away like a man who has learned renunciation, almost indeed like a sick man who shrinks from any intensity of contact. And then, striding through his adjacent dressing-room, he passed a punching-ball that hung there; he gave it a blow far swifter and harder than is usual in moods of resignation or states of weakness.
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|-
| align="right" colspan="3" | — Robert Musil, ''The Man Without Qualities'', [Mus, 8]
|}
With the tacit extension map <math>\epsilon</math>''J'' and the enlargement map E''J'' well in place, the difference map D''J'' can be computed along the lines displayed in Table 41, ending up, in this instance, with an expansion of D''J'' over the cells of [''u'', ''v''].
With the tacit extension map <math>\epsilon</math>''J'' and the enlargement map E''J'' well in place, the difference map D''J'' can be computed along the lines displayed in Table 41, ending up, in this instance, with an expansion of D''J'' over the cells of [''u'', ''v''].
=====Differential of Conjunction=====
=====Differential of Conjunction=====
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By deploying discourse throughout a calendar, and by giving a date to each of its elements, one does not obtain a definitive hierarchy of precessions and originalities; this hierarchy is never more than relative to the systems of discourse that it sets out to evaluate.
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|-
| align="right" colspan="3" | — Michel Foucault, ''The Archaeology of Knowledge'', [Fou, 143]
|}
Finally, at long last, the differential proposition d''J'' can be gleaned from the difference proposition D''J'' by ranging over the cells of [''u'', ''v''] and picking out the linear proposition of [d''u'', d''v''] that is "closest" to the portion of D''J'' that touches on each point. The idea of distance that would give this definition unequivocal sense has been referred to in cautionary quotes, the kind we use to distance ourselves from taking a final position. There are obvious notions of approximation that suggest themselves, but finding one that can be justified as ultimately correct is not as straightforward as it seems.
Finally, at long last, the differential proposition d''J'' can be gleaned from the difference proposition D''J'' by ranging over the cells of [''u'', ''v''] and picking out the linear proposition of [d''u'', d''v''] that is "closest" to the portion of D''J'' that touches on each point. The idea of distance that would give this definition unequivocal sense has been referred to in cautionary quotes, the kind we use to distance ourselves from taking a final position. There are obvious notions of approximation that suggest themselves, but finding one that can be justified as ultimately correct is not as straightforward as it seems.
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He had drifted into the very heart of the world. From him to the distant beloved was as far as to the next tree.
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|-
| align="right" colspan="3" | — Robert Musil, ''The Man Without Qualities'', [Mus, 144]
|}
Let us venture a guess about where these developments might be heading. From the present vantage point, it appears that the ultimate answer to the quandary of distances and the question of a fitting measure may be that, rather than having the constitution of an analytic series depend on our familiar notions of approach, proximity, and approximation, it will be found preferable, and perhaps unavoidable, to turn the tables and let the orders of approximation be defined in terms of our favored and operative notions of formal analysis. Only the aftermath of this conversion, if it does converge, could be hoped to prove whether this hortatory form of analysis and the cohort idea of an analytic form — the limitary concept of a self-corrective process and the coefficient concept of a completable product — are truly (in practical reality) the more inceptive and persistent of principles and really (for all practical purposes) the more effective and regulative of ideas.
Let us venture a guess about where these developments might be heading. From the present vantage point, it appears that the ultimate answer to the quandary of distances and the question of a fitting measure may be that, rather than having the constitution of an analytic series depend on our familiar notions of approach, proximity, and approximation, it will be found preferable, and perhaps unavoidable, to turn the tables and let the orders of approximation be defined in terms of our favored and operative notions of formal analysis. Only the aftermath of this conversion, if it does converge, could be hoped to prove whether this hortatory form of analysis and the cohort idea of an analytic form — the limitary concept of a self-corrective process and the coefficient concept of a completable product — are truly (in practical reality) the more inceptive and persistent of principles and really (for all practical purposes) the more effective and regulative of ideas.
=====Remainder of Conjunction=====
=====Remainder of Conjunction=====
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<p>I bequeath myself to the dirt to grow from the grass I love,<br>
<p>I bequeath myself to the dirt to grow from the grass I love,<br>
If you want me again look for me under your bootsoles.</p>
If you want me again look for me under your bootsoles.</p>
Missing me one place search another,<br>
Missing me one place search another,<br>
I stop some where waiting for you</p>
I stop some where waiting for you</p>
|-
|
| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 88]
|}
Let us now recapitulate the story so far. In effect, we have been carrying out a decomposition of the enlarged proposition E''J'' in a series of stages. First, we considered the equation E''J'' = <math>\epsilon</math>''J'' + D''J'', which was involved in the definition of D''J'' as the difference E''J'' – <math>\epsilon</math>''J''. Next, we contemplated the equation D''J'' = d''J'' + r''J'', which expresses D''J'' in terms of two components, the differential d''J'' that was just extracted and the residual component r''J'' = D''J'' – d''J''. This remaining proposition r''J'' can be computed as shown in Table 47.
Let us now recapitulate the story so far. In effect, we have been carrying out a decomposition of the enlarged proposition E''J'' in a series of stages. First, we considered the equation E''J'' = <math>\epsilon</math>''J'' + D''J'', which was involved in the definition of D''J'' as the difference E''J'' – <math>\epsilon</math>''J''. Next, we contemplated the equation D''J'' = d''J'' + r''J'', which expresses D''J'' in terms of two components, the differential d''J'' that was just extracted and the residual component r''J'' = D''J'' – d''J''. This remaining proposition r''J'' can be computed as shown in Table 47.
====Analytic Series : Coordinate Method====
====Analytic Series : Coordinate Method====
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And if he is told that something ''is'' the way it is, then he thinks: Well, it could probably just as easily be some other way. So the sense of possibility might be defined outright as the capacity to think how everything could "just as easily" be, and to attach no more importance to what is than to what is not.
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|-
| align="right" colspan="3" | — Robert Musil, ''The Man Without Qualities'', [Mus, 12]
|}
Table 50 exhibits a truth table method for computing the analytic series (or the differential expansion) of a proposition in terms of coordinates.
Table 50 exhibits a truth table method for computing the analytic series (or the differential expansion) of a proposition in terms of coordinates.
====Terminological Interlude====
====Terminological Interlude====
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Lastly, my attention was especially attracted, not so much to the scene, as to the mirrors that produced it. These mirrors were broken in parts. Yes, they were marked and scratched; they had been "starred", in spite of their solidity …
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|-
| align="right" colspan="3" | — Gaston Leroux, ''The Phantom of the Opera'', [Ler, 230]
|}
At this point several issues of terminology have accrued enough substance to intrude on our discussion. The remarks of this Section are intended to accomplish two goals. First, I call attention to important aspects of the previous series of Figures, translating into literal terms what they depict in iconic forms, and I restress the most important structural elements that they indicate. Next, I prepare the way for taking on more complex examples of transformations, whose target universes have more than a single dimension.
At this point several issues of terminology have accrued enough substance to intrude on our discussion. The remarks of this Section are intended to accomplish two goals. First, I call attention to important aspects of the previous series of Figures, translating into literal terms what they depict in iconic forms, and I restress the most important structural elements that they indicate. Next, I prepare the way for taking on more complex examples of transformations, whose target universes have more than a single dimension.
===Taking Aim at Higher Dimensional Targets===
===Taking Aim at Higher Dimensional Targets===
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The past and present wilt . . . . I have filled them and<br>
emptied them,<br>
emptied them,<br>
And proceed to fill my next fold of the future.</p>
And proceed to fill my next fold of the future.
|-
|
| align="right" | — Walt Whitman, ''Leaves of Grass'', [Whi, 87]
|}
In the next Subdivision I consider a logical transformation ''F'' that has the concrete type ''F'' : [''u'', ''v''] → [''x'', ''y''] and the abstract type ''F'' : ['''B'''<sup>2</sup>] → ['''B'''<sup>2</sup>]. From the standpoint of propositional calculus, the task of understanding such a transformation is naturally approached by parsing it into component maps with 1-dimensional ranges, as follows:
In the next Subdivision I consider a logical transformation ''F'' that has the concrete type ''F'' : [''u'', ''v''] → [''x'', ''y''] and the abstract type ''F'' : ['''B'''<sup>2</sup>] → ['''B'''<sup>2</sup>]. From the standpoint of propositional calculus, the task of understanding such a transformation is naturally approached by parsing it into component maps with 1-dimensional ranges, as follows:
<br><font face="courier new">
<br><font face="courier new">
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{| align="center" border="1" cellpadding="4" cellspacing="0" style="background:lightcyan; font-weight:bold; text-align:center; width:96%"
|+ Table 65. Induced Transformation on Propositions
|+ '''Table 65. Induced Transformation on Propositions'''
|- style="background:paleturquoise"
|- style="background:paleturquoise"
| ''X''<sup> •</sup>
| ''X''<sup> •</sup>
<font face="courier new">
<font face="courier new">
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{| align="center" border="1" cellpadding="8" cellspacing="0" style="background:lightcyan; font-weight:bold; text-align:center; width:96%"
|+ Table 66-i. Computation Summary for ''f''‹''u'', ''v''› = ((''u'')(''v''))
|+ '''Table 66-i. Computation Summary for ''f''‹''u'', ''v''› = ((''u'')(''v''))'''
|
|
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{| align="left" border="0" cellpadding="1" cellspacing="0" style="background:lightcyan; font-weight:bold; text-align:center; width:100%"
<font face="courier new">
<font face="courier new">
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{| align="center" border="1" cellpadding="8" cellspacing="0" style="background:lightcyan; font-weight:bold; text-align:center; width:96%"
|+ Table 66-ii. Computation Summary for g‹''u'', ''v''› = ((''u'', ''v''))
|+ '''Table 66-ii. Computation Summary for g‹''u'', ''v''› = ((''u'', ''v''))'''
|
|
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{| align="left" border="0" cellpadding="1" cellspacing="0" style="background:lightcyan; font-weight:bold; text-align:center; width:100%"
{| align="center" border="1" cellpadding="0" cellspacing="0" style="background:lightcyan; font-weight:bold; text-align:center; width:96%"
{| align="center" border="1" cellpadding="0" cellspacing="0" style="background:lightcyan; font-weight:bold; text-align:center; width:96%"
|+ Table 67. Computation of an Analytic Series in Terms of Coordinates
|+ '''Table 67. Computation of an Analytic Series in Terms of Coordinates'''
|
|
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==Epilogue, Enchoiry, Exodus==
==Epilogue, Enchoiry, Exodus==
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It is time to explain myself . . . . let us stand up.
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|-
| align="right" colspan="3" | — Walt Whitman, ''Leaves of Grass'', [Whi, 79]
|}
==References==
==References==
