 Process theists generally regard the notion of creation ex nihilo, as explained above, as going hand-in-hand with the idea that the relations between God and the world are one-way relations. God creates, but the creatures lack all creative power, the one wholly uncreated, the other wholly uncreative (Hartshorne 1970, 9). It is not within the ability of any creature, according to this view, to make a difference to God. Aquinas’s way of expressing this asymmetry is to say that the relation from God to the creatures is real (for it makes a difference, all the difference, to them) whereas the relation from the creatures to God is rational, or in the mind only (for the existence of the creatures makes no difference to the being of God) (Summa Theologica I, Q 13, a. 7). Aquinas borrows, and places in a Christian context, Aristotle’s terms of “pure act” and “unmoved mover” to apply to God. To say that God is pure act is to say that anything God could be, God already is—there is no potentiality in God for any type of change. To say that God is the unmoved mover is to say that the divine moves others but is unmoved by another—this includes the idea that God is impassible, literally, without feeling or emotion.