Modality

Modality (from Lat. modus), a philosophical term applied by Kant, who, in treating of our judgments, reduced them to the four heads of quantity, quality, relation, and modality. In reference to modality, he teaches, they are either problematic, or assertory, or apodictical. Hence the category of modality includes possibility and impossibility, existence and non-existence, necessity or contingency. But existence and non-existence should have no place; the contingent and the necessary: are not different from being. Kant was not, however, the first to use the term modality. Aristotle may not have used it himself in the four modal propositions which he defined and opposed (Περὶ ἑρμηνεαίς, c. 12-14), but it is to be found among his commentators and the scholastic philosophers. See Krauth's Fleming, Vocabulary of Philos. (N.Y., Sheldon & Co.) pages 320, 321; Dict. des Sciences Philosoph. s.v.