Category:Universal Quantifier

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This category contains results about the Universal Quantifier.


The symbol $\forall$ is called the universal quantifier.

It expresses the fact that, in a particular universe of discourse, all objects have a particular property.


That is:

$\forall x:$

means:

For all objects $x$, it is true that ...


In the language of set theory, this can be formally defined:

$\forall x \in S: \map P x := \set {x \in S: \map P x} = S$

where $S$ is some set and $\map P x$ is a propositional function on $S$.