Why A Posteriori Arguments Against God’s Existence Fail
[The argument is further developed here]
Many argue that God does not exist on a posteriori, or empirical, grounds. Consider, for instance, the problem of evil:
- If God were to exist, there would not be any gratuitous evil in the world.
- There is gratuitous evil in the world.
- Therefore, God does not exist.
The argument is certainly a valid modus tollens deduction. Much ink has been spilled by theists to defend against this argument. But when the argument is presented to a theist, he should ask the proponent to put in the leg-work. Ask why theists ought to think the premises are true. In particular, ask whythe first premise is true.
There are only so many conditions under which Premise 1 would be true. Either the antecedent is true and the consequent is true, or the antecedent is false. But it would be odd to defend the truth of the first premise by arguing that the antecedent is false, since that would beg the question of the argument. I take the first premise to be a counterfactual statement suggesting that in possible worlds were God exists, gratuitous evil does not exist. But unless the concept of God is logically coherent, how would we know that in a possible world where God exists, it necessarily would be the case that gratuitous evil would not? It seems to me that one could only be justified in making that supposition if, at the very least, one presumes that God is logically possible and that his existence is relevant to a certain set of states of affairs. Otherwise, one would have to admit that just about any state of affairs is implied by the supposition that God exists, including contradictory states of affairs, e.g. gratuitous evil would exist in great quantities.
It seems to me that if one wants to defend the soundness of an argument like the argument from evil in a non-question begging way, then it must be supposed that God, a necessary being, is logically possible. If it is argued that the first premise is true because God is logically impossible, then any defense for the truth of Premise 1 would beg the question for the conclusion, i.e. the defense would amount to arguing that the antecedent “God exists” is necessarily false, which is clearly the conclusion that the argument is trying to reach.
If the non-theist wants to argue in a non-question begging manner, she must explicate precisely what relevant aspects of the concept of God entails the state of affairs she suggests. But in the process, she must admit that there is at least a possible world where God exists along with those states of affairs. And if God is logically possible, then God necessarily exists. But if God, a necessary being, is possible, then God exists in all possible worlds including the actual world. This means that the first premise is false since all possible states of affairs can obtain given the existence of a necessary being. God’s existence would have to cohere with any possible state of affairs, including those that exist in this world. Therefore, no state of affairs could count against God’s existence, including gratuitous evil, if gratuitous evil is logically possible.
So the non-theist, in defending an a posteriori argument like the problem of evil, must either fallaciously beg the question, or if she argues that the counterfactual premises is substantive, then it is clear that the premise is false. Either way, the argument will not run.
Note that this dilemma would work against any a posteriori argument where it is assumed that God’s existences necessarily entails some state of affairs.