Single Idea 16854

[catalogued under 2. Reason / B. Laws of Thought / 4. Contraries]

Full Idea

All pairs of contraries entail a pair of contradictories, since one member of such a pair always entails the negation of the other. P&Q and not-P are contraries, but the first entails P, which is contradictory of not-P.

Gist of Idea

Contrary pairs entail contradictions; one member entails negation of the other

Source

Peter Lipton (Inference to the Best Explanation (2nd) [2004], 09 'Is the best')

Book Reference

Lipton,Peter: 'Inference to the Best Explanation (2nd ed)' [Routledge 2004], p.156