Single Idea 192

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

Full Idea

To everything that admits of a contrary there is one contrary and no more.

Gist of Idea

Only one thing can be contrary to something

Source

Plato (Protagoras [c.391 BCE], 332c)

Book Reference

Plato: 'Protagoras and Meno', ed/tr. Guthrie,W K C [Penguin 1956], p.65


A Reaction

The sort of thing for which a modern philosopher would demand a proof (and then reject when the proof couldn't be found), where a Greek is happy to assert it as self-evident. I can't think of a counterexample.