 Monadic predicate calculus

Monadic predicate calculus is a type of logical system that focuses on predicates involving only one variable (hence "monadic"). In mathematical logic, predicate calculus (or predicate logic) is an extension of propositional logic that allows for the use of quantifiers and predicates. In monadic predicate calculus, predicates are unary, meaning they take a single argument. For example, if \( P(x) \) is a predicate, it can express properties of individual elements in a domain.