more from René Descartes

Single Idea 5005

[catalogued under 11. Knowledge Aims / B. Certain Knowledge / 5. The Cogito]

Full Idea

There is a contradiction in conceiving that what thinks does not (at the same time as it thinks) exist. Hence this conclusion I think, therefore I am, is the first and most certain that occurs to one who philosophises in an orderly way.

Gist of Idea

I think, therefore I am, because for a thinking thing to not exist is a contradiction


René Descartes (Principles of Philosophy [1646], I.07)

Book Reference

Descartes,René: 'Philosophical Essays and Correspondence', ed/tr. Ariew,Roger [Hackett 2000], p.232

A Reaction

The classic statement of his argument. The significance here is that it seems to have the structure of an argument, as it involves 'philosophising', which leads to a 'contradiction', and hence to the famous conclusion. It is not just intuitive.