_ratio_ and _sermo_ existed within him. In a certain sense then, he was never alone, for he thought and spoke inwardly. If even men can carry on conversations with themselves and make themselves objects of reflection, how much more is this possible with God.[537] But as yet he was the only _person_.[538] The moment, however, that he chose to reveal himself and sent forth from himself the word of creation, the Logos came into existence as a real being, before the world and for the sake of the world. For "that which proceeds from such a great substance and has created such substances cannot itself be devoid of substance." He is therefore to be conceived as permanently separate from God "secundus a deo consititutus, perseverans in sua forma"; but as unity of substance is to be preserved ("_alius pater, alius filius, alius non aliud_"--"_ego et pater unum sumus ad substantiae unitatem, non ad numeri singularitatem dictum est_"--"_tres unum sunt, non unus_"--"the Father is one person and the Son is another, different persons not different things", "_I and the Father are one_ refers to unity of substance, not to singleness in number"--"the three are one thing not one person"), the Logos must be related to the Father as the ray to the sun, as the stream to the source, as the stem to the root (see also Hippolytus, c. Noetum 10).[539] For that very reason "Son" is the most suitable expression for the Logos that has emanated in this way ([Greek: kata merismon]). Moreover, since he (as well as the Spirit) has the same substance as the Father ("unius substantia" = [Greek: homoousios]) he has also the same _power_[540] as regards the world. He has all might in heaven and earth, and he has had it _ab initio_, from the very beginning of time.[541] On the other hand this same Son is only a part and offshoot; the Father is the whole; and in this the mystery of the economy consists. What the Son possesses has been given him by the Father; the Father is therefore greater than the Son; the Son is subordinate to the Father.[542] "Pater tota substantia est, filius vero derivatio totius et portio".[543] This paradox is ultimately based on a philosophical axiom of Tertullian: the whole fulness of the Godhead, i.e., the Father, is incapable of entering into the finite, whence also he must always remain invisible, unapproachable, and incomprehensible. The Divine Being that appears and works on earth can never be anything but a part of the transcendent Deity. This Being must be a derived existence, which has already in some fashion a finite element in itself, because it is the hypostatised Word of creation, which has an origin.[544] We would assert too much, were we to say that Tertullian meant that the Son was simply the world-thought itself; his insistance on the "unius substantiae" disproves this. But no doubt he regards the Son as the Deity depotentiated for the sake of self-communication; the Deity adapted to the world, whose sphere