Cognitive Scaffold

Preparing your thinking workspace

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MENTAL MODEL · M8249

Proof by Contradiction

Proof by Contradiction
StructureHigh supportLogic
Included
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Version 1.0.0 · Updated 2026-07-30

CORE DEFINITION

Assume the conclusion is false, derive a contradiction, and thereby prove the conclusion true.

SCAFFOLDING EFFECT

psychology

Reduce cognitive load

Indirect proof. When direct proof is difficult, take a detour from the opposite side.

anchor

Anchor fast decisions

To prove proposition P, first assume not P, derive a contradiction, and then conclude that P holds; it is a fundamental indirect proof method in mathematics and logic.

MINIMUM ACTION

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Source support: Explicit

  • link
    en.wikipedia.orghttps://en.wikipedia.org/wiki/Reductio_ad_absurdumZH · Explicit
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