Entry 0032: Grammar of ens and esse
Concerning the significations of ens and esse, it is instructive to turn our attention to an important point of Latin grammar.
Just as laudans/laudantis is the present active participle for the Latin verb laudare (laudo, laudare, laudavi, laudatus), ens/entis is the present active participle of the Latin verb esse (sum, esse, fui, futurus.)
Laudans/laudantis is translated into English as ‘praising,’ a verbal adjective used to modify the noun that refer to ‘someone who is now exercising the action of praising.’ But ens/entis is more than just a verbal adjective. In the context of the 'philosophy of being,' ens/entis is most of the time translated into English as a noun, ‘being,’ to signify ‘that which, in any way whatsoever, is.’
According to Aquinas our minds conceive everything sub ratione entis: Quidquid cadit in intellectu, oportet quod cadat sub ratione entis, he says in De Virtutibus 1, 2, ad 8, “Whatever is grasped by the intellect must fall under the notion of being.”
Now, as mentioned above, Aquinas is aware of the fact that the terms ens/entis and esse signify in more than one way. He is explicit on this in De Potentia 7, 2, ad 1, when he says:
Ens et esse dicitur dupliciter: quandoque enim significat essentiam rei, sive actum essendi; quandoque vero significat veritatem propositionis, etiam in his quae esse non habent: sicut dicimus quod caecitas est, quia verum est hominem esse caecum.
Ens and esse may be taken in two ways (Metaph. x, 13, 14). Sometimes they signify the essence of a thing and the act of being, and sometimes they denote the truth of a proposition even in things that have no being: thus we say that blindness is because it is true that a man is blind.