Entity. Ens. The latter of these words is a participial form derived from esse, and signifying something that exists. It stands in the same relation to essentia that the Greek ὀν does to ὀυσία. Entia, existences, are divided into entia rationis, which can be figured by the mind, but have no external reality, as a man a thousand feet high, and entia realia.
Entitas, entity, was used by the schoolmen as the general and abstract term for existence. An ens was a being, entitas beinghood. Everything that is has that which constitutes its being, its entity. The entity of animals lies in their animality, of men in their humanity. Whether entities in this the true sense of the word have any reality is the question at issue between Nominalists and Realists.
The word ens not being vernacular, and there being a strong though pernicious tendency in modern speech to use the abstract and general term to denote the concrete specimen, as in the case of locality and many others, entity is now employed where the schoolmen would have spoken of ens. An entity means with us something that exists, a nonentity that which does not.
Ens was also used by the schoolmen to denote existence in the abstract, and was thus one of the ante-predicaments or transcendentals. See Transcendental. It was antecedent to and implied in any category, even that of substance.
Everyone knows Milton’s academical exercise composed at the age of nineteen, wherein Ens appears as the father of the ten predicaments, and addresses his eldest son Substance.