Logic / Unit 4 Logic 118 short lesson, about 20 seconds
Negation
Captions available
The idea
~p reverses the truth value of p.
In practice
If "the store is open" is true, ~(the store is open) is false.
Where people slip
Negate the whole statement, not a word inside it. "Not both" and "both not" are different claims.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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