intensional logic

Intensional logic is a branch of logic that deals with the meanings of linguistic expressions, such as propositions and concepts. It contrasts with extensional logic, which focuses on the range of applicability or the specific objects a term denotes.12

Key aspects of intensional logic include:
* Meaning and Truth: It explores how meanings, synonymy, and logical necessity relate to truth, often using the concept of "possible worlds". A proposition, for instance, can be understood as a function that maps possible worlds to truth values.13
* First and Second Intentions: In scholastic logic, "first intention" refers to knowledge of a thing as it is in itself, while "second intention" is knowledge of the thing as it is known. Logic itself was considered the study of second intentions.4
* Modal Notions: Intensional logic is closely related to modal logic, which deals with concepts like possibility and necessity.15

This type of logic is crucial for understanding hypothetical and counterfactual reasoning, where the truth of conditional statements is examined.6