The traditional definition of God credits him with three attributes: moral perfection, omniscience, and omnipotence. These are supposed to be logically independent, with none entailing the others. But that is not obviously correct: How is moral perfection possible without omniscience and omnipotence? How is it possible to be omnipotent without also being omniscient? Isn’t omniscience a type of omnipotence—a power to see and know everything? In fact, can’t we simply define God in terms of omnipotence, since his other attributes flow from this? If God is omnipotent he must be morally perfect, since he has the power to be morally perfect, and why would he not exercise that power? And if he is omnipotent he must be omniscient, since omniscience is an epistemic power. At the least he has the power to be both morally perfect and all knowing, given that he is all powerful. Thus omnipotence seems to be basic in the definition of God. God differs from lesser beings precisely in having powers they do not have—moral powers, epistemic powers, and other powers (causing earthquakes, healings, etc.). God is replete with power, overflowing with it, by no means lacking in it. Any power there is, he has.
God essentially lacks certain powers as a condition of being who he is.
But is that right? Does God have every power? He has the power to create and destroy universes, but does he have the power to sneeze or digest food or pick his nose? Those powers require possession of a body with a certain anatomy, but God has no such body, being disembodied. Does he have the power to decay or split or emit radiation? How could he have these powers given his immaterial nature? Does he have the power to come down with a cold or be bed-ridden or have the runs? Surely not: God has the powers that are proper to his divine nature, not any old powers that things of other natures have—animals, plants, atoms. God essentially lacks certain powers as a condition of being who he is. He has the powers of a god not of a worm or cactus plant. Everything must lack something in order to be something, i.e., to have a determinate nature.
Does God have the moral powers of Satan or of a petty human sinner? Does he have the power to feel pleasure at the suffering of an innocent child? Does he have the power to relish the demotion of an office rival? Does he have the power to long for the death of an enemy? No: God has the power to feel only virtuous emotions and to perform only virtuous actions—he is incapable of petty jealousy or vindictive revenge. It is simply not in God’s nature to be subject to base feelings. Even to be capable of such feelings is alien to God’s nature. He exists beyond base emotions, being pure through and through. Certainly it would not make him more godlike to be capable of the lowest human failings. So it is wrong to say that God is by definition all powerful; he is only powerful within the limits of his nature. With respect to the powers he has by that nature, he is limitlessly powerful, but he does not have every power that everything in the world has—for that he would have to be the world. But God stands apart from the world, having a different nature from that of the world; he is a being unto himself.
If we want God to be literally all-powerful, we will end up with a Spinozistic pantheism, which is tantamount to the denial of God’s existence as traditionally conceived. But if we choose to restrict the powers that God has, then we can no longer define him as all-powerful. There cannot be a god that has all powers (and to the maximum degree): for such a god would not be a god but a strange hybrid of the mortal and the divine—a being of mixed nature, neither one thing nor the other. A sneezing, digesting, nose-picking god is no god. Nor can it be that God merely has the potential to do these things while never actually doing them: for first, to have even the potential is already to place God in the wrong ontological category; and second, if he were to exercise these powers that would immediately deprive him of his godlike status—he would become at best a godhuman hybrid (like Jesus). If God were to pick his nose one day, he would thereby cease to be God. So having that power is no part of his nature.
(We should distinguish actually having certain powers from the ability to transform oneself into an entity with certain powers. Maybe God has the ability to transform himself into a worm at will, but that doesn’t imply that he now has the powers of a worm. And if he did so transform himself, he would have converted himself into a non-god, because no worm is a god— though a worm might once have been a god.)
The difficulty for God is to specify what kind of omnipotence he is supposed to possess. And the dilemma is obvious: either he has powers that do not properly belong to his nature as divine, or he lacks powers that other things possess, thus being less than all-powerful. The concept of an all-powerful being is actually, when you think about it, incoherent. To be a thing of a certain type is necessarily to have a limited range of powers, because powers and natures go hand in hand.
About the Author
Dr. Colin McGinn is a British philosopher who has been a professor of philosophy at University College London, the University of Oxford, Rutgers University, and the University of Miami. He is the author of over 20 books on philosophy, including The Character of Mind, The Problem of Consciousness, The Meaning of Disgust, Inborn Knowledge, Prehension, and Philosophy of Language.
Source: A Disproof of God’s Existence