Logic / Unit 5 Logic 209 short lesson, about 20 seconds
Transposition
Captions available
The idea
p ⊃ q :: ~q ⊃ ~p.
In practice
"If hired, then vetted" equals "if not vetted, then not hired."
Where people slip
Both terms negate and swap. Doing one without the other yields the twins from 150 and 152.
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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