According to Wikipedia,

Aristotle didn't have the notion of actus essendi. In fact, the contribution of Aquinas to the philosophy of being is precisely that he discovered that all Aristotelian acts were in reality "potency" with respect to the actus essendi.

What does this mean in layman's terms? I'm familiar with the distinction between act and potency, but what are "Aristotelian acts"?

Medievalists seem to think this issue of actus essendi is a big deal, but I can't even understand the difference between "being" and "act of being".

  • "Aristotelian acts" are entelechies, actualizations of potential into being. In Aristotle, the driving force of entelechy is the form being actualized, but this creates a problem with distinguishing actual from possible, because the latter can be described via essence + accidents just as well. And the concrete, substances, appears to be reduced to quivers of properties (forms), which are all abstract, to greater or lesser degree. Actus essendi adds a metaphysical source of concreteness/actuality, which is also dynamic, active. In medieval theology it was crucial as securing a role for God.
    – Conifold
    Commented May 22, 2023 at 9:48
  • Well, ya gotta understand the milieu in which all this was taking place, oui? There are at least 2 watchamcallits in this ancient tale and the idea is weave a, if possible, beauitful story with 'em. Do note, we're not exactly in friendly territory here. Be careful ... got that?
    – Hudjefa
    Commented May 22, 2023 at 10:35
  • See Gilson, L'Etre et l'essence ( eng. tr. Being and some philosophers) that answers precisely your question. Short answer: greek philosophy identified " being" to " being such and such" where " such and such" denote " essential predicates" ( being a diamant, being a man). So, the ultimate act was identified tu essence . Aquinas says : in order to be in the full sense of the term, that is to exist, a further act or actualisation is necessary : actus essendi or act of standing out of nothingness, that requires a participation to God's "esse" ( pure act). Commented May 28, 2023 at 9:49
  • @Hudjefa Where do you go with questions like these?
    – Doubt
    Commented May 17 at 10:23


You must log in to answer this question.

Browse other questions tagged .