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Single Idea 22271

[filed under theme 4. Formal Logic / A. Syllogistic Logic / 1. Aristotelian Logic ]

Full Idea

It was Aristotle who initiated the use of the letter of the (Greek) alphabet 'schematically', to stand for an unspecified piece of language of some appropriate grammatical type.

Gist of Idea

Aristotle was the first to use schematic letters in logic

Source

report of Aristotle (Prior Analytics [c.328 BCE]) by Michael Potter - The Rise of Analytic Philosophy 1879-1930 02 'Aris'

Book Ref

Potter,Michael: 'The Rise of Anaytic Philosophy 1879-1930' [Routledge 2020], p.11


A Reaction

Did he invent it from scratch, or borrow it from the mathematicians? Euclid labels diagrams with letters.


The 15 ideas from 'Prior Analytics'

Aristotle's said some Fs are G or some Fs are not G, forgetting that there might be no Fs [Bostock on Aristotle]
Aristotle was the first to use schematic letters in logic [Aristotle, by Potter]
Aristotelian syllogisms are three-part, subject-predicate, existentially committed, with laws of thought [Aristotle, by Hanna]
Aristotelian sentences are made up by one of four 'formative' connectors [Aristotle, by Engelbretsen]
Aristotelian identified 256 possible syllogisms, saying that 19 are valid [Aristotle, by Devlin]
Aristotle replaced Plato's noun-verb form with unions of pairs of terms by one of four 'copulae' [Aristotle, by Engelbretsen/Sayward]
Aristotle places terms at opposite ends, joined by a quantified copula [Aristotle, by Sommers]
Aristotle's logic is based on the subject/predicate distinction, which leads him to substances and properties [Aristotle, by Benardete,JA]
Aristotelian logic has two quantifiers of the subject ('all' and 'some') [Aristotle, by Devlin]
Linguistic terms form a hierarchy, with higher terms predicable of increasing numbers of things [Aristotle, by Engelbretsen]
Affirming/denying sentences are universal, particular, or indeterminate [Aristotle]
Deduction is when we suppose one thing, and another necessarily follows [Aristotle]
There are three different deductions for actual terms, necessary terms and possible terms [Aristotle]
A deduction is necessary if the major (but not the minor) premise is also necessary [Aristotle]
Aristotle listed nineteen valid syllogisms (though a few of them were wrong) [Aristotle, by Devlin]