more from Stoic school

Single Idea 20788

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

Full Idea

A double contradictory is the contradictory of a contradictory, for example, 'It s not the case that it is not day'. It posits that it is day.

Gist of Idea

The contradictory of a contradictory is an affirmation

Source

report of Stoic school (fragments/reports [c.200 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 07.69

Book Reference

'The Stoics Reader', ed/tr. Inwood,B/Gerson,L.P. [Hackett 2008], p.18


A Reaction

Seems like common sense to the stoics, but verifying the double negative may be a different procedure to verifying the affirmative. 'Are you happy?' 'Well .I'm not unhappy'. 'Is it day yet?' 'Well, it's not night'.