| Noun | 1. | logical relation - a relation between propositions relation - an abstraction belonging to or characteristic of two entities or parts together logic - the branch of philosophy that analyzes inference contradictory - two propositions are contradictories if both cannot be true (or both cannot be false) at the same time contrary - a logical relation such that two propositions are contraries if both cannot be true but both can be false transitivity - (logic and mathematics) a relation between three elements such that if it holds between the first and second and it also holds between the second and third it must necessarily hold between the first and third reflexiveness, reflexivity - (logic and mathematics) a relation such that it holds between an element and itself modality, mode - a classification of propositions on the basis of whether they claim necessity or possibility or impossibility conditional relation, logical implication, implication - a logical relation between propositions p and q of the form `if p then q'; if p is true then q cannot be false |