Logic / Unit 5 Logic 208 short lesson, about 20 seconds
Double Negation
Captions available
The idea
p :: ~~p.
In practice
"It's not the case that the motion didn't pass" — the motion passed.
Where people slip
Trivial-looking, constantly needed: MT and DS demand exact negation matches, and DN is what manufactures them (194's cliffhanger, resolved).
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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