Logic / Unit 4 Logic 121 short lesson, about 20 seconds
Exclusive "Or"
Captions available
The idea
Exclusive "or" — one or the other but not both — is built, not primitive: (p ∨ q) · ~(p · q).
In practice
"The entrée comes with soup or salad." Order both and watch the waiter apply exclusion.
Where people slip
Symbolize exclusively only when context clearly demands it. When unsure, inclusive.
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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