Logic / Unit 6 Logic 276 short lesson, about 20 seconds
Identity
Captions available
The idea
a = b asserts that a and b name the same individual; identicals are intersubstitutable everywhere.
In practice
Twain = Clemens. Whatever's true of Twain is true of Clemens — same man, two names.
Where people slip
Identity is a relation between things, not names. The names differ; the individual doesn't.
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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