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About the Society - Friends of the SEP Society

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© Metaphysics Research Lab, CSLI, Stanford University Join | Log In | Help 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 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

  • The PDF versions of SEP entries are generated from the HTML source using professional typographic software so as to achieve a high-quality visual appearance when displayed or printed. For example, our PDFs are formatted in two wide-column landscape mode, use a nice font, have right- and left-justified paragraphs, and are optionally formatted in US Letter and A4 paper sizes, and in Single-Column half-sheets. By contrast, our HTML entries display by default in a single column and print by default in portrait mode, with ragged-right edges.
  • Some web browsers don't support the mathematical, logical, and special Unicode characters we use in our HTML documents. But our PDF versions embed all of these special characters in the document.
  • The PDF versions combine all of the documents, such as footnotes and supplements, that may be associated with an entry into a single (printable) file. Thus, a single file can be stored for offline viewing (when you are not connected to the Internet). By contrast, the footnotes and supplementary documents in the HTML versions of SEP entries have to be viewed (printed) separately, and for some entries, you have to separately download and store all these files and all the graphics if you want to be able to view the file when you are offline, disconnected from the Internet.
  • This single file format (described in the previous bullet point) for entries may be particularly useful for storing, accessing, and reading on mobile devices. We recommend using our single-column half-sheet PDFs for such devices for easier reading on smaller displays. See the SEP FAQ V.3 and V.4 which explain how to download and view our single-column half-sheet PDFs on a Kindle and an iPhone, respectively. (You are welcome to write to us with information about how to view single-column PDFs on other mobile devices, so we can include that information.)
  • Since the content of PDF versions is generated from the HTML versions of entries held in recent SEP Archives, they (as well as those archived HTML versions) can be used as the source of quotations and for citation purposes. Please follow the PDF Citation guidelines. By contrast, the ‘active’ HTML versions of SEP entries are not appropriate for citation, since they might be updated or otherwise revised at any time.
  • The PDF versions include a titlepage that displays (at the top) the URL that forms part of the proper citation information. If the PDF is printed, this information stays with the printed document. By contrast, the HTML versions of SEP entries have no titlepages, and when printed, no URL is included with the printed document (unless your browser supplies it). Instead the HTML versions contain a link to a page that shows the proper citation information.

Membership Levels

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

AssociateStudentProfessional Membership Dues $10/year $5/year $25/year Access to the entire PDF Library (1,500+ entries) # of Different Entries Downloadable Per 24 Hours Maximum of 5 Maximum of 5 Unlimited Access to New/Revised PDFs Published Each Quarter Keep Track of Your Download History Opt-in Email Notification When Entries Are Updated Option to Upgrade

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.

Copyright © 2014The Metaphysics Research Lab
Center for the Study of Language and Information, Stanford University, Stanford, CA 94305