PhilPapers: what has been written on a question
The hardest part of starting research is not reading. It is knowing what exists. Without that, you write a chapter and then discover that the question was settled in 1998, or that the position you thought was yours has a name and three standard objections.
PhilPapers is the instrument the discipline built for this, and it is free to use.
What it is
A comprehensive index and bibliography of philosophy, maintained by the community of philosophers under the general editorship of David Bourget (Western Ontario) and David Chalmers (ANU/NYU). It monitors journals, books and open-access repositories, and currently indexes over three million entries across roughly six thousand categories.
It also hosts PhilArchive, the largest open-access archive in philosophy, where authors deposit preprints and accepted versions of papers that are otherwise behind paywalls.
Why it works as a source
Because the categories are curated by area editors rather than generated automatically. Browsing Philosophy of Religion or Ancient Greek and Roman Philosophy gives you a structured map of subfields, not a keyword soup.
And because of the archive. A great deal of philosophy sits behind subscriptions you do not have; a substantial share of it is legally available here in a version you may cite.
How to use it
Browse the category before searching. Searching assumes you already know the term of art. Browsing teaches you the term of art, which is usually the real obstacle.
Set up an alert. You can follow a category and receive new entries. Ten minutes a month keeps you current in a way no social feed does.
Check for an open version. Before giving up on a paywalled article, look for it here. Often the author has deposited it.
A note on honesty in research
Citing only what you could reach is not a method; it is a constraint. Knowing what exists and saying plainly that you could not obtain it is far more defensible than writing as though the inaccessible literature did not exist.
Image: The Four Evangelists, Jacob Jordaens, c. 1625. Musée du Louvre, Paris, public domain. Four accounts of the same story, read side by side: the first lesson in knowing what has already been written.
