Of the Medium of the Angelic Knowledge

Next in order, the question arises as to the medium of the angelic knowledge. Under this heading there are three points of inquiry:

(1) Do the angels know everything by their substance, or by some species?

(2) If by species, is it by connatural species, or is it by such as they have derived from things?

(3) Do the higher angels know by more universal species than the lower angels?