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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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The library

Capsules

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

All1,028Fact599Proven130Theory89Hypothesis71Contested90Debunked48
geography236biology88physics67history54medicine45astronomy33psychology26mathematics26chemistry20engineering20astrophysics19neuroscience19anthropology18art18
Filtered byContestedneuroscienceClear all

Results

Showing 1 to 8 of 8

NewestMost votedA to Z
Contested

Why We Sleep

Sleep is universal among animals with nervous systems, is regulated with precision, and is fatal to eliminate. What it is for remains unresolved, and…

byCapsule
0 votes0 reviews
Aug 4, 2026
Contested

Mirror Neurons

Mirror neurons are cells that fire both when an animal performs an action and when it observes the same action performed by another. They were…

byCapsule0 votes0 reviewsAug 3, 2026
Contested

The Critical Period Hypothesis

The critical period hypothesis holds that there is a window early in life during which language is acquired readily and after which full acquisition…

byCapsule0 votes0 reviewsAug 3, 2026
Contested

Why Do We Dream

Dreams, the vivid stories the mind plays out during sleep, are universal yet deeply mysterious. That we dream is obvious; why we dream, and what…

byCapsule0 votes0 reviewsJun 12, 2026
Contested

What Causes Alzheimer's Disease

Alzheimer's disease is the most common cause of dementia, slowly destroying memory and thinking. That it damages the brain is clear, but what…

byCapsule0 votes0 reviewsJun 12, 2026
Contested

Are Animals Conscious?

Whether animals have conscious experiences, an inner life of feelings and awareness, is a deep and genuinely contested question. That many animals…

byCapsule0 votes0 reviewsJun 11, 2026
Contested

The Hard Problem of Consciousness

The hard problem of consciousness is the question of why and how physical processes in the brain give rise to subjective experience, the felt quality…

byCapsule0 votes0 reviewsApr 20, 2026
Contested

Free Will

Free will is the question of whether people are truly free to choose their actions, or whether every choice is the inevitable product of prior…

byCapsule0 votes0 reviewsApr 9, 2026