In logic, a predicate is a symbol that represents a property or a relation.
is a predicate that applies to the individual constants
According to Gottlob Frege, the meaning of a predicate is exactly a function from the domain of objects to the truth values "true" and "false".
In the semantics of logic, predicates are interpreted as relations.
For instance, in a standard semantics for first-order logic, the formula
would be true on an interpretation if the entities denoted by
Since predicates are non-logical symbols, they can denote different relations depending on the interpretation given to them.