Single Idea 2258

[catalogued under 11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito]

Full Idea

Doubtless I exist if I persuade myself of something. But there is some powerful and cunning deceiver who is deliberately deceiving me. Then too there is no doubt that I exist, if he is deceiving me.

Gist of Idea

I must even exist if I am being deceived by something

Source

René Descartes (Meditations [1641], §2.25)

Book Reference

Descartes,René: 'Discourse on Method/The Meditations', ed/tr. Sutcliffe,F.E. [Penguin 1968], p.103