## FANDOM

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Existential instantiation is a rule of inference of predicate logic that allows one to infer from a formula quantified with the Existential quantifer a formula in which the bound variable is freed and the variable is replaced with a new variable or constant. In symbols:

$\exists x \phi (x) \vdash \phi (a)$

## RestrictionsEdit

• The variable or constant replacing the bound variable must be a new variable or constant.