A method for establishing semantic equivalence between a plurality of concepts including: providing an Orthogonal Semantic Equivalence Map in which first, second, and third extensional concept models are related; selecting or de-selecting a concept in the first concept model; selecting or deselecting a (relation, concept) pair representing an intensional relation from a concept in the first concept model to a concept in the second concept model over a concept in the third concept model; determining a subset of intensional relations from the selected concepts in the first concept model to concepts in the second concept model; determining a set of concepts from the first concept model that are related to concepts in the second concept model over the selected (relation, concept) pairs; and determining the narrowest common extension of the set of concepts from the first, second, or third concept models that are related over the selected intensional relations.