Logic / Unit 7 Logic 343 short lesson, about 20 seconds
Necessary and Sufficient Causes
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The idea
A necessary cause must be present for the effect; a sufficient cause guarantees it. Most causes of interest are neither alone — they're contributing conditions.
In practice
Oxygen: necessary for the fire, sufficient for nothing.
Where people slip
"The" cause is usually a selection from a causal field, picked out by our interests. The insurance report and the fire marshal may both be right.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Unlocks
- Nothing yet depends on this.
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