An
existential quantifier is the symbol ∃ in
predicate calculus. It roughly represents the phrase "for some" or "there exists". For example
- ∃ x (x^{2}=25)
means "there exists an
x such that
x^{2}=25".
The unique existential quantifer is the symbol ∃!.
For example,
- ∃! x (x-2) = 4
means "there exists an unique x such that x-2 = 4".
History of the Quantifer
TODO
See Existential quantification for details.
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