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Truth Classification

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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 bymedicineClear all

Results

Showing 41 to 60 of 81

NewestMost votedA to Z
medicine
Hypothesis

The Gut-Brain Axis

The proposal that gut microbes influence mood, behaviour and neurological disease, and that altering them could treat psychiatric and…

byCapsule
0 votes0 reviews
medicine
Hypothesis

The Dopamine Hypothesis of Schizophrenia

The proposal that psychosis results from excess dopamine signalling. It has organised psychiatry for sixty years, it was inferred backwards from…

byCapsule0 votes0 reviews
medicine
Proven

Semmelweis and Handwashing

A Hungarian obstetrician worked out in 1847 that doctors were killing women in childbirth by carrying something on their hands from the dissection…

byCapsule0 votes0 reviews
medicine
Hypothesis

The Serotonin Hypothesis of Depression

The proposal that depression is caused by low serotonin, and that antidepressants work by correcting it. The popular version of this claim is not…

byCapsule0 votes0 reviews
medicine
Proven

Magnetic Resonance Imaging

A way of photographing the inside of a living body in any plane, at high resolution, without ionising radiation, by making hydrogen nuclei resonate…

byCapsule0 votes0 reviews
medicine
Proven

The Randomised Controlled Trial

Assign people to treatments by chance, and the groups differ only by chance. It is a simple idea, it is the most reliable method medicine has for…

byCapsule0 votes0 reviews
medicine
Hypothesis

The Amyloid Hypothesis

The proposal that Alzheimer's disease is caused by the accumulation of amyloid beta protein in the brain. It has directed the field for over thirty…

byCapsule0 votes0 reviews
genetics
Hypothesis

The Thrifty Gene Hypothesis

The proposal that genes favouring efficient fat storage were advantageous during famine and became harmful once food became abundant, explaining the…

byCapsule0 votes0 reviews
medicine
Proven

The Circulation of the Blood

William Harvey demonstrated in 1628 that blood circulates in a closed loop driven by the heart. He proved it by measurement, against a doctrine that…

byCapsule0 votes0 reviews
medicine
Proven

General Anaesthesia

Surgery without pain, without memory, and without movement, produced reliably millions of times a year. That it works is beyond question. How it…

byCapsule0 votes0 reviews
nutrition
Contested

Salt and Blood Pressure

That reducing salt lowers blood pressure is established. Whether population-wide salt reduction reduces deaths, and how low is low enough, is one of…

byCapsule0 votes0 reviews
nutrition
Contested

Dietary Fat and Heart Disease

The proposition that saturated fat raises cholesterol and thereby causes heart disease shaped dietary guidelines across the developed world for fifty…

byCapsule0 votes0 reviews
epidemiology
Contested

Overdiagnosis

Overdiagnosis is the correct detection of a condition that would never have caused symptoms or harm during the person's life. It is not misdiagnosis…

byCapsule0 votes0 reviews
neuroscience
Theory

Neuroplasticity

Neuroplasticity is the brain's capacity to change its structure and function in response to experience, injury, and learning. It overturned a…

byCapsule0 votes0 reviews
materials science
Proven· Replicated

Shape-Memory Alloys

A shape-memory alloy is a metal that returns to a remembered shape when heated, having been deformed while cool. The effect looks like a trick and is…

byCapsule0 votes0 reviews
immunology
Proven· Replicated

Immunological Memory

Immunological memory is the reason surviving a disease usually protects against getting it again, and the reason vaccination works at all. It is…

byCapsule0 votes0 reviews
immunology
Contested

The Hygiene Hypothesis

The hygiene hypothesis is the proposal that reduced exposure to microbes in early childhood leaves the immune system poorly calibrated, and that this…

byCapsule0 votes0 reviews
immunology
Theory· Scientific

Autoimmunity

Autoimmunity is the immune system attacking the body it belongs to. Around a hundred distinct autoimmune conditions are recognised, together…

byCapsule0 votes0 reviews
immunology
Theory

Herd Immunity

Herd immunity is the protection an unvaccinated person receives when enough of the people around them are immune that a chain of transmission cannot…

byCapsule0 votes0 reviews
genetics
Proven· Replicated

CRISPR Gene Editing

CRISPR is a method for cutting DNA at a chosen location, which makes editing a genome a routine laboratory procedure rather than a specialist feat.…

byCapsule0 votes0 reviews
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