Philosophy / Unit 7 Philosophy 0266 short lesson, about 20 seconds
The Is-Ought Gap
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The idea
Hume's is-ought gap: no set of purely factual premises entails a normative conclusion—somewhere, an "ought" premise must be supplied.
In practice
"Smoking causes disease, therefore you should quit" hides a premise: you ought to avoid disease. State it, and the argument is honest.
Where people slip
The gap does not make ethics arbitrary—it makes the ought-premises the part worth debating.
Your place on the trail
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