4: Further, Gregory (Hom. xxiv in Evang.) places the
"Principalities" above the "Powers." These therefore are not placed
immediately above the Archangels, as Dionysius says (Coel. Hier. ix).

_On the contrary,_ Dionysius (Coel. Hier. vii), places in the highest
hierarchy the "Seraphim" as the first, the "Cherubim" as the middle,
the "Thrones" as the last; in the middle hierarchy he places the
"Dominations," as the first, the "Virtues" in the middle, the
"Powers" last; in the lowest hierarchy the "Principalities" first,
then the "Archangels," and lastly the "Angels."

_I answer that,_ The grades of the angelic orders are assigned by
Gregory (Hom. xxiv in Ev.) and Dionysius (Coel. Hier. vii), who agree
as regards all except the "Principalities" and "Virtues." For
Dionysius places the "Virtues" beneath the "Dominations," and above
the "Powers"; the "Principalities" beneath the "Powers" and above the
"Archangels." Gregory, however, places the "Principalities" between
the "Dominations" and the "Powers"; and the "Virtues" between the
"Powers" and the "Archangels." Each of these placings may claim
authority from the words of the Apostle, who (Eph. 1:20,21)
enumerates the middle orders, beginning from the lowest saying that
"God set Him," i.e. Christ, "on His right hand in the heavenly places
above all Principality and Power, and Virtue, and Dominion." Here he
places "Virtues" between "Powers" and "Dominations," according to the
placing of Dionysius. Writing however to the Colossians (1:16),
numbering the same orders from the highest, he says: "Whether
Thrones, or Dominations, or Principalities, or Powers, all things
were created by Him and in Him." Here he places the "Principalities"
between "Dominations" and "Powers," as does also Gregory.

Let us then first examine the reason for the ordering of Dionysius,
in which we see, that, as said above (A. 1), the highest hierarchy
contemplates the ideas of things in God Himself; the second in the
universal causes; and third in their application to particular
effects. And because God is the end not only of the angelic
ministrations, but also of the whole creation, it belongs to the first
hierarchy to consider the end; to the middle one belongs the universal
disposition of what is to be done; and to the last belongs the
application of this disposition to the effect, which is the carrying
out of the work; for it is clear that these three things exist in
every kind of operation. So Di