  In this passage, Aquinas makes it clear that in cases involving relations of reason—such as self-identity or God’s relation to the world—the relata are related, not by their relations (since these are mere beings of reason and hence dependent on the activity of the mind), but by what he refers to here as the cause of their  relations.[40]  Now, in the case of a man’s being self-identical, Aquinas says the cause is just “the unity of his substance,” where by this he seems to mean that what makes a man identical to himself is just the man himself. Again, in the case of God’s being Lord he says that the cause is “the power to compel subjects”. In the case of God, however, Aquinas does not think the power to compel subjects is distinct from its subject, namely, the divine nature. Hence, he maintains that what makes it true that God is Lord is nothing but God, his creatures, and some property or attribute of the creatures.