Metaphysics

What sort of things exist, and how do we know they exist?

These are the problems that Descartes undertook in the 17th Century.  He decided to doubt everything that could possibly be doubted, from the existence of trees, to the existence of God.  What he worked out was that he (Descartes) existed, because he was thinking - if he was thinking, then he must exist, he reasoned - 'Cogito ergo sum' - I think, therefore I am.  From this base, he was able to show that other things existed, including God, the external world, and other people.  

Our course traces Descartes' thinking, and asks whether his method and conclusions can be questioned.