Logic / Unit 4 Logic 156 short lesson, about 20 seconds
Constructive Dilemma
Captions available
The idea
(p ⊃ q) · (r ⊃ s); p ∨ r; therefore q ∨ s. Valid — two conditionals, one guaranteed trigger.
In practice
If we litigate, we pay counsel; if we settle, we pay damages. We litigate or settle. We pay something.
Where people slip
The conclusion is a disjunction. The dilemma never tells you which horn you're on.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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