Logic / Unit 4 Logic 120 short lesson, about 20 seconds
Disjunction
Captions available
The idea
p ∨ q is inclusive: true when either disjunct is true, or both. False only when both fail.
In practice
"The alarm triggers if there's smoke or heat" — both at once certainly counts.
Where people slip
Inclusive is the default. English sometimes means exclusive — the next video handles that.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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