 Note that (a) is a past state of affairs. Presumably, it is not possible for an efficient cause to occur later than its effect. However, an agent’s bringing about a state of affairs is a kind of efficient causation. Therefore, it is not possible for an agent to bring about anything that is in the past. In other words, it is impossible for any agent to have power over what is past. Hence, no agent, not even an omnipotent one, can bring it about that (a) obtains. Likewise, despite the fact that (b) can be brought about prior to \(t\), the impossibility of an agent’s having power over what is past implies that after t even an omnipotent agent cannot bring it about that (b) obtains. In the case of (c), prior to Parmenides’s first lecture, an omnipotent agent can bring about (c). But once Parmenides has lectured, even an omnipotent agent cannot bring it about that (c) obtains. As for (d), prior to the Amazon’s third flooding, an omnipotent agent can bring it about that (d) obtains, while after the Amazon’s third flooding, even an omnipotent agent cannot bring it about that (d) obtains. (e) introduces a special difficulty. Although it is obvious that (e) could not be brought about by an omnipotent agent, it can be argued plausibly that it is possible for a non-omnipotent agent to bring about (e) by causing a snowflake to fall, provided that no omnipotent agent ever  exists.[1]  But, as we argued earlier, a maximally powerful being need not have the power to bring about every state of affairs that any other being could. Lastly, while if the libertarian theory of free will is correct, an omnipotent agent (who is, of course, other than Plato) cannot bring about (f), apparently a non-omnipotent agent, namely, Plato, can bring it about that (f) obtains.