Logic / Unit 6 Logic 270 short lesson, about 20 seconds
Existential Generalization
Captions available
The idea
From Fa, derive (∃x)Fx. What's true of a named thing is true of something.
In practice
Ms, therefore (∃x)Mx. Socrates is mortal, so something is.
Where people slip
EG is as generous as UI. The two generalizations differ wildly in strictness; the two instantiations do too — crosswise.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
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