Cognitive Scaffold

Preparing your thinking workspace

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MENTAL MODEL · M12480

Contrapositive

Contrapositive
StructureHigh supportLogic
Included
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Version 1.0.0 · Updated 2026-07-30

CORE DEFINITION

If the original proposition is "If P then Q", its contrapositive is "If not Q then not P", and the two are logically equivalent.

SCAFFOLDING EFFECT

psychology

Reduce cognitive load

The key to indirect proof. When direct proof is difficult, proving the contrapositive is often easier, and it is a common technique in mathematical proofs.

anchor

Anchor fast decisions

The proposition "If P then Q" is logically equivalent to its contrapositive "If not Q then not P", which can be used for proof.

MINIMUM ACTION

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Source support: Explicit

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