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DebunkedThe PolygraphThe instrument popularly called a lie detector, which records breathing, blood pressure, pulse and skin conductance dur…

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1,028 capsules, each one classified by the strength of its evidence.

All1,028 Fact599 Proven130 Theory89 Hypothesis71 Contested90 Debunked48

geography236 biology88 physics67 history54 medicine45 astronomy33 psychology26 mathematics26 chemistry20 engineering20 astrophysics19 neuroscience19 anthropology18 art18

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Fact

The Internal Combustion Engine

An engine in which fuel burns inside the working chamber, pushing a piston or turning a rotor directly. It displaced the steam engine because it is…

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Aug 5, 2026