What Did Descartes Certainly Know?

It is well-known that the philosopher Descartes, while searching for some truth beyond all doubt, observed: Je pense, donc je suis. He restated this idea in various places, once in Latin, as: Cogito, ergo sum. The phrase is widely known as The Cogito and is usually translated into English as ‘I think, therefore I am’. Descartes thus concluded that he knew something with absolute certainty.

Descartes’ line of enquiry here has some similarities with a practice adopted by students of non-duality and others: saying ‘not this’ to all thoughts and finite conceptions in search of the Self and the Real. The non-dual philosophy holds that the existence of Self is incontrovertible and requires no further proof. So here we find what seems to be common ground between the theory and practice of non-duality and a pre-eminent thinker in the Western philosophical tradition. This article will consider how far the two approaches do overlap, and also where their methods and conclusions differ, in order to see what help and guidance both offer in our own pursuit of Self-discovery.