More Ad Hominem attacks please!
Has the sociology or psychology of philosophers ever been studied? Philosophy students and teachers must make a fairly interesting societal group, and there are almost certainly various norms and cultural habits that we hold esoterically.
In addition to mere curiosity, we might be able to find interesting biases that affect how philosophy tends to be done, and thereby make room for their correction. Sexism in philosophy is an issue that has been raised recently, and no doubt there are other prejudices and biases at work in the profession.
Relatedly, Richard Chappell suggested that having failed to study History of Philosophy is no great loss. However, analogously, history of philosophy can help us spot biases as to how philosophy is done. For instance, if philosophers are usually merely people of their time, this gives us reason to doubt some of the opinions of philosophers in the present.
More broadly than each of these points, I tend to think that human bias is understudied by philosophers. We like to think of ourselves as good at thinking, but this cannot be true if we do not take the time to understand common human biases.
(The sadly-now-late Susan Hurley originally got me thinking about this with her paper The Public Ecology of Responsibility (.doc), which makes for depressing reading in terms of the human irrationality it highlights)
I don't know if this is
I don't know if this is relevant but I think it's interesting. My observations of Philosophy departments have led to the following conclusions: Philosophy undergraduates are weird. They have strange hair, strange clothes and a strange disregard for major sports events. As one moves up the academic ladder, however, philosophers become more normal. Post-graduate students are less weird than the youngsters and professors of philosophy are totally normal guys who have ordinary lives, relationships with women and everything!
One could speculate for hours on whether the activity of philosophy makes people more reasonable or whether the reality of working in the subject weeds out the weirdos. What I find really interesting, though, is that the exact opposite is true of every other academic subject.