Logic / Unit 4 Logic 127 short lesson, about 20 seconds
Necessary vs. Sufficient Conditions
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The idea
A sufficient condition sits in the antecedent; a necessary condition sits in the consequent.
In practice
Oxygen is necessary for fire — Fire ⊃ Oxygen. It is nowhere near sufficient.
Where people slip
Necessary-versus-sufficient confusion drives real disasters: mistaking a required condition for a guaranteeing one.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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