Single Idea 18801

[catalogued under 5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / c. not]

Full Idea

Explanations of classical negation assume that knowing what it is for the truth-condition of some statement to obtain, independently of recognising it to obtain, we thereby know what it is for it NOT to obtain; but this presupposes classical negation.

Gist of Idea

Classical negation is circular, if it relies on knowing negation-conditions from truth-conditions

Source

Michael Dummett (The Logical Basis of Metaphysics [1991], p.299), quoted by Ian Rumfitt - The Boundary Stones of Thought 1.1

Book Reference

Rumfitt,Ian: 'The Boundary Stones of Thought' [OUP 2015], p.4


A Reaction

[compressed wording] This is Dummett explaining why he prefers intuitionistic logic, with its doubts about double negation.

Related Idea

Idea 18799 Intuitionists can accept Double Negation Elimination for decidable propositions [Rumfitt]