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?