I was approached by the What Would Plato Do club here at the University of Toronto and asked to give a paper for their first philosophical function of the year, which I did today. It was great fun. The title I chose was "Naturalism, Infinity, and the Cartesian Argument from Reason" - basically it was just a roughed-out adaptation of some of my work on Malebranche for an audience of mixed undergraduates. It turned out, however, to be a good topic for such a group; I focused on Malebranche's arguments, which are fairly lucid, but I also touched briefly on its historical root in Descartes's Third Meditation and the more recent work, along parallel lines, of Thomas Nagel in The Last Word. People who are very early in their program would still be able to recognize the issues in Descartes, and people who have a deeper interest in more recent analytic stuff than in the early modern period were able to relate to Nagel's adaptation of Wittgenstein. Also, everyone is always fascinated by infinites, so that worked to good advantage, too. There are several different things called 'the argument from reason'; what I called the Cartesian Argument from Reason is the view that:
1. Reason involves in some way infinity and related properties;
2. Because of these properties, reason cannot be entirely explained in terms of finite experience of finite objects + finite psychological operations.
The sort of explanation rejected in (2) is one thing that could be called 'naturalism' (always a slippery term), and was for the purpose of the talk the only sense of naturalism I was considering.
It was great fun; chatting with undergrads about philosophical topics always is.