Hi, My roommate claims that it is impossible for an omnipotent being to exist. His logic is that if a being can create a rock so big it cannot lift it, then that being is not omnipotent because its lifting power is not infinite. But also, if it cannot create the rock so big it cannot lift, then it's creation power is not infinite. And because of this paradox, an omnipotent being cannot possibly exist. My boss was a philosophy major in school. He claims that this explanation is completely wrong. However, I do not understand his explanation as he said it very quickly and with many names of old philosophers and theorems and such that I cannot remember. So who is right? Regardless of whether or not an omnipotent being does exist or not, can one exist? Thanks.

There are two traditional theistic answers to this question (well, three, if you count: “you’re a heretic, where are my matches”). The first, favored by Descartes, is that God’s powers are truly unlimited, and He is not even limited by the laws of logic. It is not for us finite and imperfect beings to understand or criticize an infinite and perfect being’s ways. The second, favored by Thomas Aquinas, is like Richard Heck’s answer above. To be omnipotent means to be able to do anything; a contradiction is not a thing: therefore not being able to create a stone so heavy one can’t lift it is not a thing that can’t be done. To some readers this puzzle might seem silly, but it actually mirrors some contemporary controversies about the nature of logic. Are logical inferences hardwired into our brains? That is similar to Descartes’ answer. Are logical inferences constitutive of rationality? That is similar to Aquinas’ answer.