Descartes is generally regarded as the first modern philosopher, and one of his innovations is to put epistemology at the center of modern philosophy's concerns. Whereas, for example, the pre-Socratic philosophers were most concerned with metaphysics (what is it that all things have in common? How does one thing change into another thing?),
Descartes believed that we must first determine what we can know before we can address any other questions. In your discussions with each other this week, think about what it means to know something and especially what it means to be sure that you know (as opposed to simply believing something to be true). Do you think Descartes provided an adequate response to the skeptic through his "method of doubt?"
Another important legacy of Descartes' philosophy is that he argued for a sharp separation between the mind and the body. This distinction is one than many people today take for granted (the mind or soul is distinct from the body) but few consider seriously the implications of this distinction (what contemporary philosophers call the "mind/body problem").
For example, if the mind is a different kind of thing than the body, then how do the two interact? If I make a mental decision to move my arm, then just exactly how does that cause my arm to move?
If I feel tired or sick, how exactly can that affect my ability to concentrate?
So, consider these issues, and of course feel free to raise any other issues you'd like.