Changes

MyWikiBiz, Author Your Legacy — Friday November 29, 2024
Jump to navigationJump to search
→‎6.33. Sign Relational Complexes: move fragments to talk page
Line 8,717: Line 8,717:     
Presently, the distinction between indirect pointers and direct pointers, that is, between virtual copies and actual views of an objective domain, is not yet relevant here, being a dimension of variation that the discussion is currently abstracting over.
 
Presently, the distinction between indirect pointers and direct pointers, that is, between virtual copies and actual views of an objective domain, is not yet relevant here, being a dimension of variation that the discussion is currently abstracting over.
  −
<p align="center">'''Fragments'''</p>
  −
  −
I would like to record here, in what is topically the appropriate place, notice of a number of open questions that will have to be addressed if anyone desires to make a consistent calculus out of this link notation.  Perhaps it is only because the franker forms of liaison involved in the couple <math>a \widehat{~} b\!</math> are more subject to the vagaries of syntactic elision than the corresponding bindings of the anglish ligature <math>(a, b),\!</math> but for some reason or other the circumflex character of these diacritical notices are much more liable to suggest various forms of elaboration, including higher order generalizations and information-theoretic partializations of the very idea of <math>n\!</math>-tuples and sequences.
  −
  −
One way to deal with the problems of partial information &hellip;
  −
  −
'''Relational Complex?'''
  −
  −
{| align="center" cellspacing="8" width="90%"
  −
| <math>L ~=~ L^{(1)} \cup \ldots \cup L^{(k)}\!</math>
  −
|}
  −
  −
'''Sign Relational Complex?'''
  −
  −
{| align="center" cellspacing="8" width="90%"
  −
| <math>L ~=~ L^{(1)} \cup L^{(2)} \cup L^{(3)}\!</math>
  −
|}
  −
  −
Linkages can be chained together to form sequences of indications or <math>n\!</math>-tuples, without worrying too much about the order of collecting terms in the corresponding angle brackets.
  −
  −
{| align="center" cellspacing="8" width="90%"
  −
|
  −
<math>\begin{matrix}
  −
a \widehat{~} b \widehat{~} c
  −
& = &
  −
(a, b, c)
  −
& = &
  −
(a, (b, c))
  −
& = &
  −
((a, b), c).
  −
\end{matrix}</math>
  −
|}
  −
  −
These equivalences depend on the existence of natural isomorphisms between different ways of constructing <math>n\!</math>-place product spaces, that is, on the associativity of pairwise products, a not altogether trivial result (Mac&nbsp;Lane, CatWorkMath, ch.&nbsp;7).
  −
  −
Higher Order Indications (HOIs)?
  −
  −
{| align="center" cellspacing="8" width="90%"
  −
|
  −
<math>\begin{matrix}
  −
\widehat{~} x & = & (~, x) & ?
  −
\\[4pt]
  −
x \widehat{~} & = & (x, ~) & ?
  −
\\[4pt]
  −
\widehat{~}~\widehat{~} x & = & (~, (~, x)) & ?
  −
\\[4pt]
  −
x \widehat{~}~\widehat{~} & = & ((x, ~), ~) & ?
  −
\end{matrix}</math>
  −
|}
  −
  −
In talking about properties and classes of relations, one would like to refer to ''all relations'' as forming a topic of potential discussion, and then take it as a background for contemplating &hellip;
  −
  −
In talking and thinking, often in just that order, about properties and classes of relations, one is always invoking, explicitly or implicitly, a particular background, a limited field of experience, actual or potential, against which each object of ''discussion and thought'' figures.  Expressing the matter in the idiom of logical inquiry, one brings to mind a preconceived universe of discourse <math>U\!</math> or a restricted domain of discussion <math>X,\!</math> and then contemplates &hellip;
  −
  −
This direction of generalization expands the scope of PIRs by means of an analogical extension, and can be charted in the following manner.  If the name of a relation can be taken as a PIR to elementary relations, that is, if the formula of an <math>n\!</math>-place relation can be interpreted as a proposition about <math>n\!</math>-tuples, then a PIR to relations themselves can be formulated as a proposition about relations and thus as a HOPE about elementary relations or <math>n\!</math>-tuples.
  −
  −
One way to extend the generic brand of partiality among relations in a non-trivial direction can be charted as follows.  If the name or formula of a relation is a PIR to elementary relations, that is, if a sign or expression of an <math>n\!</math>-place relation is interpreted as a proposition about <math>n\!</math>-tuples, then a PIR to relations &hellip;
      
===6.34. Set-Theoretic Constructions===
 
===6.34. Set-Theoretic Constructions===
12,080

edits

Navigation menu