Internet Encyclopedia of Philosophy

• 1. Introduction

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  The Internet Encyclopedia of Philosophy reaches 8.2 million unique viewers in any given twelve-month period. That makes it the most visited encyclopedia of professionally written philosophy articles on the internet. But behind that traffic sits a quietly rigorous operation: every article is peer-reviewed, blind-refereed, and written for an audience of students and faculty who are curious about philosophy but who are not specialists. The questions worth following are how this resource came to exist, who built it, and what principles have kept it authoritative for three decades.

• 2. Founding and Early Shape

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  Philosopher James Fieser founded the IEP in 1995, operating it through a non-profit organization with the explicit goal of making scholarly philosophy accessible. That combination, rigorous scholarship made genuinely readable, set the tone from the start. Bradley Dowden joined as co-general editor in 1999, and by the 2010s the two of them supervised a staff of thirty faculty members serving as subject-area editors, alongside numerous volunteers. The whole website was redesigned in 2009 when it transitioned to the open-source content management system WordPress, giving the encyclopedia a more modern and searchable home.

• 3. How the Encyclopedia Works

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  Thirty subject-area editors sit between the two general editors and the authors, recruiting writers and referees for their respective corners of philosophy. The blind-refereeing process is managed at the area-editor level, meaning reviewers evaluate submissions without knowing who wrote them. Contribution is generally by invitation rather than open submission, and contributors are drawn from 35 countries, according to the encyclopedia's own representative list. Each article follows a consistent structure: a brief survey or overview comes first, followed by the body of the article, and then an annotated bibliography.

• 4. Readers and Recognition

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  Analytics from Similarweb and Google Analytics break down exactly how those millions of visitors arrive: 75 percent come through internet searches, 18 percent through direct access, and 5 percent through referrals from other reference websites and university library guides. The American Library Association includes the IEP in its listing of Best Free Reference Sites. The Federation of Australasian Philosophy in Schools Associations lists it as an online philosophy resource. EpistemeLinks names it one of the outstanding resources in philosophy on the internet. And many university philosophy guides point to it as a reliable source, meaning its credibility is now baked into academic infrastructure worldwide. By 2025 the encyclopedia had grown to around 900 articles, a figure that reflects the slow, careful pace at which peer-reviewed work accumulates.