Cognitive Scaffold

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MENTAL MODEL · M6171

Hume's Guillotine

Hume's Guillotine
StructureHigh supportLogic
Included
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Version 1.0.0 · Updated 2026-07-30

CORE DEFINITION

"Is" cannot derive "Ought." You cannot simply because facts are a certain way (e.g., "nature is survival of the fittest") infer that they ought to be that way (e.g., "so we should also be survival of the fittest"). Facts and values are two separate domains.

SCAFFOLDING EFFECT

psychology

Reduce cognitive load

Counter the naturalistic fallacy. When someone uses "what exists is reasonable" or "this is tradition" to justify an evil act, use Hume's Guillotine to cut off their logical chain. Facts (Is) can serve as reference, but they are never the basis for morality (Ought).

anchor

Anchor fast decisions

"Is" cannot derive "Ought." You cannot infer what ought to be from what is. Facts and values are two separate domains; facts can be a reference but are never the basis for morality.

MINIMUM ACTION

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Source support: Explicit

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    en.wikipedia.orghttps://en.wikipedia.org/wiki/Is%E2%80%93ought_problemZH · Explicit
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