The Cogito

Quite simply, 'the cogito' is the first thing that resists Descartes method of doubt, and is therefore indubitable. Descartes states that if he doubts everything then he can at least claim that he is doubting. ie. he cannot doubt that he doubts. This is expanded on to mean that thinking cannot be doubted, and if thoughts can't be doubted, then thoughts exist.

Furthermore, if our thoughts exist, then don't we also exist? Our body might not be real, but our thoughts are, which means that - 'I think, therefore I exist'. To quote Descartes: "I am, I exist". If this were to be put in a proper argument form, then it would be:

• Everything that thinks exists.
• I am thinking.
• I am existing.

(In the meditations Descartes never says: "I think therefore I am", but he says it in a response to a criticism). Now Descartes has the foundations for existence, and can begin to build up everything else that must be true, based from the cogito.

So if some wannabe philosopher - after having watched the matrix - asks in a nasally voice: "How can you be sure that you even exist?" Simply reply: "I just think that I do".