Cartesian doubt

So let's move on from there and see what he comes up with.

He says, quote, As we have seen, Descartes employed methodic doubt with a view to discovering whether there was any indubitable truth.

And whoever knows anything at all about his philosophy knows that he founded this truth in the affirmation, I think, therefore I am.

However much I doubt, I must exist, otherwise I could not doubt.

This is the moment of the earthquake and the search for the bedrock.

He begins the rigorous application of methodical doubt to the very foundations of metaphysics.

He is searching for what philosophers call an Archimedean point, a single, absolutely unshakable, undeniable truth upon which he can leverage the entire weight of a new scientific and philosophical system.

And to find it, he pushes his first rule to the absolute extreme.

He asks himself a critical follow-up question.

Okay, I have proven that I exist, but what exactly am I?

Which is a very tricky question, because a few minutes ago, he used the methodical doubt to completely wipe away the existence of his physical body.

Exactly the problem.