What Is the Stanford Encyclopedia of Philosophy?

The Stanford Encyclopedia of Philosophy (SEP) is a scholarly, continuously updated reference work in philosophy and related disciplines, hosted at plato.stanford.edu. It is organized by editors who commission entries from scholars around the world, and it is maintained as an "up-to-date reference work" rather than a static encyclopedia. If you need a citable, expert-written overview of a philosophical topic, the SEP is designed for that purpose.

Who runs it

The SEP is edited by a team of scholars. Its Co-Principal Editors are Edward N. Zalta and Uri Nodelman, supported by an Editorial Board and a masthead of editorial staff.

Operational and financial support comes from several sources:

  • Offices of the Provost, the Dean of Humanities and Sciences, and the Dean of Research at Stanford University
  • The SEP Library Fund, which includes contributions from the National Endowment for the Humanities and membership dues from academic libraries in SEPIA
  • The O.C. Tanner SEP Fund
  • The John Perry Fund and The SEP Fund, funded by individual donors
  • The Friends of the SEP Society Fund, supported by individual members who receive benefits such as formatted PDF versions of entries

Founding support is acknowledged from the National Endowment for the Humanities, the National Science Foundation, the American Philosophical Association/Pacific Division, the Canadian Philosophical Association, and the Philosophy Documentation Center. Fundraising was supported by a grant from the William and Flora Hewlett Foundation.

The site is copyright © 2026 by The Metaphysics Research Lab, Department of Philosophy, Stanford University, and carries ISSN 1095-5054.

What you can do on the site

The SEP is built around browsing and searching entries. Its main navigation includes:

  • Search — with a separate Search Tips page
  • Browse — including a Table of Contents
  • What's New — recently added or revised entries
  • Random Entry — for open-ended exploration
  • Chronological Archives — entries organized by date
  • About — editorial information, the Editorial Board, and how to cite the SEP
  • Special Characters and Advanced Tools — for working with entry content
  • Accessibility and Contact pages

There are also support options: donating to the SEP, PDFs for Friends of the SEP Society members, and SEPIA for Libraries. Mirror sites are available, with the main site hosted at Philosophy, Stanford University, and information provided about other mirror servers.

Who it is for

The SEP is aimed at readers who need reliable, scholarly philosophy coverage:

  • Researchers and academics who need citable overviews and bibliographies
  • Students looking for an authoritative starting point on a topic
  • General readers who want a trustworthy introduction to a philosophical subject

Because entries are written by scholars and revised over time, the SEP functions as a dynamic reference rather than a fixed textbook. If your goal is a quick, expert-level orientation to a philosophical topic, it is built for that; if you need a formal citation, the site provides guidance on how to cite the SEP.

plato.stanford.edu