 First-order logic

First-order logic permits quantification over elements of a structure while its nonlogical symbols describe operations, constants, and relations.

First-order logic (FOL), also known as predicate logic or first-order predicate logic, is a formal system used in mathematical logic, philosophy, linguistics, and computer science to express statements about objects and their relationships. It expands upon propositional logic by introducing quantifiers and predicates, allowing for a more expressive representation of logical statements.

Builds on top of propositional logic, adding notably existential quantification.