PHIL 3330: Metaphysics

Free to all, but unlike Wikipedia, "each [SEP] entry is maintained and kept up to date by an expert or group of experts in the field. All entries and substantive updates are refereed by the members of a distinguished Editorial Board before they are made public. Consequently, our dynamic reference work maintains academic standards while evolving and adapting in response to new research."

"[S]ince 1967, the Encyclopedia of Philosophy, described by Booklist as 'the best and most comprehensive English-language reference source for philosophy,' has been the cornerstone of the philosophy reference shelf." A great place to begin your research or gather authoritative background information on a topic.