"existence [(esse)] taken simply insofar as it includes in itself every perfection of existing, is more eminent than life and all subsequent things, for thus existence itself has in it all the subsequent [perfections]. . . . But if existence be considered insofar as it is participated in by this thing or that, which does not receive the full perfection of existing but has imperfect existence—something true of the existence of any creature—then it is manifest that existence with a superadded perfection is more eminent. Hence Dionysius says that the living are better than the existing, and the understanding than the living."
"esse simpliciter acceptum, secundum quod includit in se omnem perfectionem essendi, praeeminet vitae et omnibus subsequentibus, sic enim ipsum esse praehabet in se omnia subsequentia. Et hoc modo Dionysius loquitur. Sed si consideretur ipsum esse prout participatur in hac re vel in illa, quae non capiunt totam perfectionem essendi, sed habent esse imperfectum, sicut est esse cuiuslibet creaturae; sic manifestum est quod ipsum esse cum perfectione superaddita est eminentius. Unde et Dionysius ibidem dicit quod viventia sunt meliora existentibus, et intelligentia viventibus."
Thomas Aquinas, Summa theologiae I-II.2.5.ad 2, trans. McInerny.
"Being is not a minimal perfection, simple existence, the fact of not being nothing, but . . . an intensive perfection that includes virtually all other other perfections."
Serge-Thomas Bonino on "The Christian rectification of Neo-Platonism by Dionysius [the Areopagite]," in "Influence du Pseudo-Denys sur la conception thomiste de l'«esse»," Bulletin de littérature ecclésiastique 94, no.3 (July-September 1993): 271 (269-273).