About the project

Facts have a history.

Not a Fact Anymore documents how accepted knowledge changes, and how factual claims shape institutional practice.

The core catalogue currently contains 303 corrected, narrowed, superseded, reclassified, or overturned claims. A separate Institutional Beliefs collection follows cases in which factual propositions became embedded in policy, medicine, law, professional practice, education, or other institutions. It traces both the current evidence and what the institutions did in response.

The site also tracks when claims changed and how long they remained defensible. Its 133-term glossary explains specialized concepts, while timelines, lifespan analysis, and category pages offer different ways of exploring the core catalogue. Institutional Beliefs is a related but separate collection that requires evidence of institutional authority and practice. Some of its claims were disputed even while institutions acted on them.

The purpose is not to ridicule earlier researchers or generations. Many discarded ideas were reasonable given the evidence and instruments available at the time. Revising a conclusion when better evidence arrives is one of the strengths of science, scholarship, and empirical inquiry.

This is a curated, open-source project. Every published claim is sourced, dates and boundaries are treated as approximations where the history demands it, and proposed entries and corrections are reviewed before publication. The Institutional Beliefs collection currently contains 100 documented cases.

How the project is made

Isaac Mattoo created and maintains the site. AI tools assist with research, drafting, translation and code; editorial decisions and publication remain his responsibility.

The catalogue has not undergone a formal independent expert review. A recorded review date refers to checking an entry for this project. The methodology explains the evidence labels, inclusion standards and limits of those dates.

If you spot an error, missing context or a source problem, suggest a correction. You can also view the project and its history on GitHub.