Whether the Son is other than the Father?

Objections

Objection 1 : It would seem that the Son is not other than the Father. For "other" is a relative term implying diversity of substance. If, then, the Son is other than the Father, He must be different from the Father; which is contrary to what Augustine says (De Trin. vii), that when we speak of three persons, "we do not mean to imply diversity."
Objection 2 : Further, whosoever are other from one another, differ in some way from one another. Therefore, if the Son is other than the Father, it follows that He differs from the Father; which is against what Ambrose says (De Fide i), that "the Father and the Son are one in Godhead; nor is there any difference in substance between them, nor any diversity."
Objection 3 : Further, the term alien is taken from "alius" [other]. But the Son is not alien from the Father, for Hilary says (De Trin. vii) that "in the divine persons there is nothing diverse, nothing alien, nothing separable." Therefore the Son is not other that the Father.
Objection 4 : Further, the terms "other person" and "other thing" [alius et aliud] have the same meaning, differing only in gender. So if the Son is another person from the Father, it follows that the Son is a thing apart from the Father.