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Single Idea 13609

[filed under theme 5. Theory of Logic / H. Proof Systems / 2. Axiomatic Proof ]

Full Idea

Frege's work supplied a set of axioms for logic itself, at least partly because it was a well-known way of presenting the foundations in other disciplines, especially mathematics, but it does not nowadays strike us as natural for logic.

Gist of Idea

Frege produced axioms for logic, though that does not now seem the natural basis for logic

Source

report of Gottlob Frege (Begriffsschrift [1879]) by David Kaplan - Dthat 5.1

Book Ref

Bostock,David: 'Intermediate Logic' [OUP 1997], p.191


A Reaction

What Bostock has in mind is the so-called 'natural' deduction systems, which base logic on rules of entailment, rather than on a set of truths. The axiomatic approach uses a set of truths, plus the idea of possible contradictions.


The 7 ideas with the same theme [proofs built up from some initially accepted truths]:

Boole's method was axiomatic, achieving economy, plus multiple interpretations [Boole, by Potter]
Frege produced axioms for logic, though that does not now seem the natural basis for logic [Frege, by Kaplan]
Quantification adds two axiom-schemas and a new rule [Bostock]
Axiom systems from Frege, Russell, Church, Lukasiewicz, Tarski, Nicod, Kleene, Quine... [Bostock]
No assumptions in axiomatic proofs, so no conditional proof or reductio [Sider]
Good axioms should be indisputable logical truths [Sider]
Geometrical axioms in logic are nowadays replaced by inference rules (which imply the logical truths) [Rumfitt]