The Semiotic square - also known as Greimas' rectangle or semantic rectangle - is a way of classifying concepts which are relevant to a given opposition of concepts, such as feminine-masculine, beautiful-ugly, etc. and of extending the relevant ontology. It has been put forth by Lithuanian linguist and semiotician Algirdas Julien Greimas, and was derived from Aristotle's logical square or square of opposition.
Starting from a given opposition of concepts S1 and S2, the semiotic square entails first the existence of two other concepts, namely ~S1 and ~S2, which are in the following relationships:
The semiotic square also produces, second, so-called meta-concepts, which are compound ones, the most important of which are:
For example, from the pair of opposite concepts masculine-feminine, we get:
Some alternative frameworks to the semiotic square have been proposed in the literature, such as conceptual graphs or matrices of concepts.