Logic / Unit 4 Logic 154 short lesson, about 20 seconds
Disjunctive Syllogism
Captions available
The idea
p or q; not-p; therefore q. Valid — eliminate one disjunct, the other stands.
In practice
The outage is hardware or software. It isn't hardware. It's software.
Where people slip
DS works by denying a disjunct. Affirming one proves nothing — next video.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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