Friends of the SEP Society
About the Friends of the SEP Society


The Stanford Encyclopedia of Philosophy (SEP) invites you to join the Friends of the SEP Society. By paying modest, annual membership dues to join the Society, members are entitled to receive certain benefits. During the year their membership is valid, members can access and download very high quality PDF (Portable Document Format, a.k.a. Acrobat) versions of SEP entries. The SEP has a comprehensive PDF Library of its entries, and after each quarterly SEP Archive is made, members can access the new PDFs that we generate for those entries that have been published or revised in any way during the previous 3 months. Student and Associate Members may download up to five different entries in any 24-hour period, whereas Professional Members have no daily limits. The members-only pages keep track of your download history, and members can ‘opt-in’ to receive an email notification from us, sent once every 3 months, informing them about any PDFs they've downloaded that have been updated in the most recent quarterly SEP Archive. Members may receive other benefits should these become available.

Goals of the Society

The SEP is currently under-funded and therefore needs to develop sources of income that are consistent with its being an open access publication. We hope that readers who both value the careful layout of our PDFs and applaud our efforts to make high-quality academic content freely available worldwide will support our endeavors by joining the Society. But in addition to raising funds, it is our goal to build a sense of community among readers who value the SEP project for the role it plays in the profession and the public at large. The Friends of the SEP Society therefore offers our readers a chance to become affiliated with the SEP community.

Example PDF Versions

Paper Size: US Letter
(8½ × 11 in)
  Paper Size: A4
(210 × 297 mm)
sample entry   sample entry in A4
Sample PDF
Entry on Turing Machines
  Sample PDF
Entry on Turing Machines

We also release our PDFs in single-column half-sheets (5½ × 8½ in)—see the Sample PDF. You might find this format especially useful for mobile devices, such as an iPhone.

The above example shows that our PDF versions offer the reader some valuable features that are not present in the freely-available HTML versions of SEP entries.

Advantages of the PDF Versions

Membership Levels

You can join the Friends of the SEP Society, using our secure online payment system, at one of the following levels:

Associate Student Professional
Membership Dues $10/year $5/year $25/year
Access to the entire PDF Library (1,350+ entries) ok ok ok
# of Different Entries Downloadable Per 24 Hours Maximum of 5 Maximum of 5 Unlimited
Access to New/Revised PDFs Published Each Quarter ok ok ok
Keep Track of Your Download History ok ok ok
Opt-in Email Notification When Entries Are Updated ok ok ok
Option to Upgrade ok ok

For purposes of security, the Friends of the SEP Society office does not store credit card information. Please do not send your credit card information by email, phone, or letter. To become a member, you must follow the link to join the Society and complete the secure online payment process.


The SEP would like to thank the William and Flora Hewlett Foundation for providing most of the funds used to build the Friends of the SEP Society website. We'd also like to thank Paul Daniell for the programming excellence he demonstrated in developing this site.