# Predicate logic facts for kids

**Predicate logic** is a system of mathematical logic. It uses predicates to express the state of certain things. It is different from propositional logic because it has the concept of *quantifiers*. This means, that it can also express things about quantity.

The best-known quantifiers are the *existence quantifier* (∃) and the *universal quantifier* (∀) . The existence quantifier says that there is at least one (thing) that matches the predicate or formula. The universal quantifier says that all the things match a certain predicate or formula.

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Predicate logic Facts for Kids. *Kiddle Encyclopedia.*