 Aquinas followed Boethius, though with greater understanding of the logical structure of the  question.[28]  Scotus, however, took a completely different approach (Lectura I 39 [1994]). Almost all medieval thinkers accepted that God’s knowledge does not depend on its objects, as human knowledge does, but brings them about. Boethius put this problem aside, but Scotus faces up directly to explaining how, if God brings about all things about by knowing them, anything can be contingent. The incompatibility is avoided, Scotus argues, if and only if God himself wills contingently. But the understanding of necessity most thirteenth-century university thinkers took from Aristotle would not allow God to will or act contingently. What is necessary, they held, is equivalent to what is always the case, and so the will of God, who all agreed exists always and never changes, is necessary. Scotus made explicit a different understanding of modality, in which possibility and necessity are not reducible to temporal conditions. God’s will is unchanging through all time, but it might have been different. (Knuuttila 1993: 139–149; and entry on  medieval theories of modality).