Logic / Unit 4 Logic 152 short lesson, about 20 seconds
Denying the Antecedent
Captions available
The idea
If p then q; not-p; therefore not-q. Invalid — always.
In practice
If it rained, the street's wet. It didn't rain. "So the street's dry" — the hydrant laughs.
Where people slip
MT's evil twin. The conditional never promised q only through p.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
- Nothing yet depends on this.
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