What makes a question a "philosophical" question? It's easy enough to understand that scientific questions, for example, don't fit here, but beyond such obvious eliminations I'm at somewhat of a loss to come up with some more rigorous criteria.

Somephilosophers think that philosophy has a special subject matter (theanalysis of concepts?) that distinguishes it from science and otherfirst-order enquiries. I don't find this persuasive (apart fromanything else, it would make philosophy trivial). In my view,philosophy deals with just the same kind of subject matter (nature,morality) as other kinds of enquiry. Even so, we can distinguish two ways in which philosophical questions are distinctive. The first way relates to the generality of the categories philosophy deals with. Wherescientists think about viruses, electrons or stars, and medicalethicists think about abortion and genetic enginerring, philosophersthink aboutspatiotemporal continuants, universals and identity, and about duty andvalue. These latter categories do not relate tospecific topics, but structure all our thinking. The second way inwhich philosophy is special cuts across the first. Not all philosophical issues are of...