[CG] Re: Differential Propositional Calculus

Differential Propositional Calculus • 7 • https://inquiryintoinquiry.com/2023/11/21/differential-propositional-calcul… All, Note. Please see the blog post linked above for the proper formats of the notations used below, as they depend on numerous typographical distinctions lost in the following transcript. Formal Development — The preceding discussion outlined the ideas leading to the differential extension of propositional logic. The next task is to lay out the concepts and terminology needed to describe various orders of differential propositional calculi. Elementary Notions — Logical description of a universe of discourse begins with a collection of logical signs. For simplicity in a first approach we assume the signs are collected in the form of a finite alphabet, ‡A‡ = {“a_1”, ..., “a_n”}. The signs are interpreted as denoting logical features, for example, properties of objects in the universe of discourse or simple propositions about those objects. Corresponding to the alphabet ‡A‡ there is then a set of logical features, †A† = {a_1, ..., a_n}. A set of logical features †A† = {a_1, ..., a_n} affords a basis for generating an n-dimensional universe of discourse, written A• = [†A†] = [a_1, ..., a_n]. It is useful to consider a universe of discourse as a categorical object incorporating both the set of points A = <a_1, ..., a_n> and the set of propositions A↑ = {f : A→B} implicit with the ordinary picture of a venn diagram on n features. Accordingly, the universe of discourse A• may be regarded as an ordered pair (A, A↑) having the type (Bⁿ, (Bⁿ → B)) and this last type designation may be abbreviated as Bⁿ +→ B, or even more succinctly as [Bⁿ]. For convenience, the data type of a finite set on n elements may be indicated by either one of the equivalent notations, [n] or *n*. Table 7 summarizes the notations needed to describe ordinary propositional calculi in a systematic fashion. Table 7. Propositional Calculus • Basic Notation • https://inquiryintoinquiry.files.wordpress.com/2020/02/propositional-calcul… Resources — Logic Syllabus • https://inquiryintoinquiry.com/logic-syllabus/ Differential Logic and Dynamic Systems • https://oeis.org/wiki/Differential_Logic_and_Dynamic_Systems_%E2%80%A2_Part… Functional Conception of Propositional Calculus • https://oeis.org/wiki/Differential_Logic_and_Dynamic_Systems_%E2%80%A2_Part… Regards, Jon cc: https://www.academia.edu/community/54Gadl