... same line of argument by saying of God (Div. Nom. v): "It is not that He is this and not that, but that He is all, as the cause of all." Secondly, from what has been already proved, God is existence itself, of itself subsistent (Q. 3, A. 4). Consequently, He must contain within Himself the whole perfection of being. For it is clear that if some hot thing has not the whole perfection of heat, this is because heat is not participated in its full perfection; but if this heat ... — Summa Theologica, Part I (Prima Pars) - From the Complete American Edition • Thomas Aquinas