 Obviously, Leibniz’s arguments against the Newtonians highlighted a fundamental difference between his interpretation of the PSR and Clarke’s: where Leibniz held what we might call the “rationalist” view that all willing, all choice, must occur for a reason—a requirement from which even the divine being is not exempt—Clarke held what we might call the “voluntarist” view that willing, or choice, itself need not occur for any reason, for it is itself a sufficient reason for some states of affairs to obtain or event to occur. From Leibniz’s point of view, this renders the will, including the divine will, opaque or unintelligible: if an agent can act or make a choice without having any reason for it, then surely the agent is not rational, and if the PSR demands anything of the world, it is that the world be rationally intelligible to us. This requirement must hold of agents and their wills as well. But from Clarke’s point of view, this requirement is too stringent, especially in the divine case: if we hold that even God must have a reason for choosing to create one state of affairs rather than another—for choosing, say, to part the Red Sea rather than the Mississippi River—then we are ipso facto restricting God’s freedom. Surely God has the freedom to choose to do anything at all, or at least, anything that does not contain or instantiate a contradiction, and for his part, Leibniz agrees that the principle of contradiction does not entail the PSR—the latter is a separate and independent principle which is necessary for metaphysics and natural philosophy to extend beyond mathematics, which requires only the principle of contradiction (Clarke and Leibniz 1717: L 2: 1). But he thinks that Clarke’s view leaves us with a God, and indeed with ordinary agents, who can act arbitrarily, with no reason at all. That is not the kind of freedom that philosophy seeks; it wishes to see agents as engaged in rational action. In their differing interpretations of the PSR, and their correspondingly distinct conceptions of freedom and reason, the debate between Leibniz and Clarke hits rock bottom.