On Whitcomb's Grounding Argument for Atheism

Abstract

Dennis Whitcomb argues that there is no God on the grounds that (i) God is omniscient, yet (ii) nothing could be omniscient due to the nature of grounding. We give a formally identical argument that concludes that one of the present co-authors does not exist. Since he does exist, Whitcomb’s argument is unsound. But why is it unsound? That is a difficult question. We venture two answers. First, one of the grounding principles that the argument relies on is false. Second, the argument equivocates between two kinds of grounding: instance-grounding and quasi-mereological grounding. Happily, the equivocation can be avoided; unhappily, avoidance comes at the price of a false premise. I. Parody One way to argue for atheism is to argue that one of the properties God is supposed to have could not be had by anything. Thus, for example, one might argue that there is no God because God is supposed to be omnipotent and nothing could be omnipotent due to a suitably subtle version of the paradox of the stone. And there are other well-known arguments of this form. Continuing in this grand tradition, Dennis Whitcomb argues that there is no God because God is supposed to be omniscient and nothing could be omniscient due to the nature of grounding and its relation to knowledge. 1 Whitcomb offers two versions of his argument, one informal and the other formal. In what follows we assess both versions. The informal version goes like this: Suppose for reductio that someone is omniscient. Then his being omniscient is partly grounded by his knowing that he is omniscient (which is one of the knowings that helps make him all-knowing). And his knowing that he is omniscient is partly grounded by his being omniscient (for knowledge is partly grounded by the truth of what is known). Since partial grounding is transitive, it follows that his being omniscient is partly grounded by his being omniscient. But this result is absurd, for nothing can partly ground itself. Hence our reductio assumption is false. That is to say, it is false that someone is omniscient. But if God exists, then he is omniscient. Therefore, God does not exist. 2 1 Dennis Whitcomb, “Grounding and Omniscience,” Oxford Studies in Philosophy of Religion 4 (2012). 2 Ibid., 5 (manuscript).