First-order logic (FOL) is a formal system using quantifiers like 'for all' and 'there exists' to reason about individuals. It's…
FDE is a logical system that allows propositions to be both true and false, or neither, rejecting the law of…
A theory is finitely axiomatizable if it can be completely defined by a finite collection of fundamental statements or axioms.…
Falsum, symbolized as ⊥, represents absolute falsity or a contradiction in logic. It's a fundamental concept used to denote statements…
Exportation is a logical principle that rewrites (P AND Q) -> R as P -> (Q -> R). It effectively…
The Explosion Principle, also known as ex falso quodlibet, states that from a contradiction, any proposition can be logically derived.…
An existential variable is a placeholder in predicate logic, bound by an existential quantifier. It signifies the existence of at…
A rule of inference in logic that allows the introduction of an existential quantifier (∃). It asserts the existence of…
Existential instantiation is a logical rule enabling the inference of a specific individual's existence from a generic existential statement. It's…
Existential import refers to the assumption that a statement implies the existence of its subject. This concept is crucial in…