Logic / Unit 6 Logic 259 short lesson, about 20 seconds
The Universal Quantifier
Captions available
The idea
(x)Fx says: every individual x is F.
In practice
(x)Mx — everything is material. A claim about the entire universe of discourse.
Where people slip
The quantifier binds its variable across its scope. What counts as "everything" is set by the universe of discourse — often restricted, always worth checking.
Your place on the trail
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