Logic / Unit 2 Logic 054 short lesson, about 20 seconds
Ostensive and Enumerative Definitions
Captions available
The idea
Ostensive definitions point at examples; enumerative definitions list members of the extension.
In practice
"'Crimson' — that color." "'Great Lake' means Superior, Michigan, Huron, Erie, or Ontario."
Where people slip
Pointing is radically underdetermined. Point at a rabbit: did you define the animal, the species, the fur?
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
- Nothing yet depends on this.
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