There are many handbooks, dictionaries, and encyclopedias that provide basic information. If you are not clear about your topic, try establishing its limits with a good definition and some introductory information. The following general sources can give you a quick overview or summary of a topic, and you can find more specialized resources in the Reference Room.
Finding Background Information
Stanford Encyclopedia of Philosophy
A dynamic encyclopedia with each entry maintained and kept up-to-date by an expert or group of experts in the field.
The Cambridge Dictionary of Philosophy
Includes an index of all names mentioned in the articles. Does not contain articles on living philosophers.
The Oxford Dictionary of Philosophy
Comprehensive in coverage. Other than primary sources mentioned in articles there are no bibliographies.
The Oxford Companion to Philosophy
Includes brief bibliographies, portraits, a chronological table and a table of logical symbols.
Routledge Encyclopedia of Philosophy
A comprehensive encyclopedia. The online version can be browsed by philosophical themes, philosophies, historical periods, and religions. Full-text entries can be searched by keyword, title, contributor, or bibliography.