Both sides would grant that if the Old Testament is true then God exists. But it would be an appeal to ignorance by the theist to simply assert that it is true unless the atheist can prove otherwise. That is, one may not say, "I am presupposing that the OT is true until you prove otherwise." And the atheist would be committing the fallacy of denying the antecedent if he or she argued that because the OT is false, it follows that God doesn't exist. Why? Because there may be other reasons besides revelation for affirming God's existence: consider, for example, as the reasons that made Plato to affirm the existence of a kind of supreme being, which he called the Good, and the reasons that made Aristotle affirm the existence of a highest being, which he called Thought. These and other reasons may be marshaled as parts of a longer argument that demonstrates that the same Supreme Being is provident (which is what both theist and atheist mean the word 'God' nowadays). These reasons may be available to us even if we are ignorant or doubtful about the truth of the OT and NT. And for an atheist to focus on the question of scripture's veracity in the face of reasons for God that are independent any revelation is to offer a red herring.
Here is a summary and comments on the essay Freedom and Resentment by PF Strawson. He makes some great points, and when he is wrong, it is in such a way as to clarify things a great deal. My non-deterministic position is much better thanks to having read this. I’ll summarize it in this post and respond in a later one. In a nutshell: PFS first argues that personal resentment that we may feel toward another for having failed to show goodwill toward us would have no problem coexisting with the conviction that determinism is true. Moral disapprobation, as an analog to resentment, is likewise capable of coexisting with deterministic convictions. In fact, it would seem nearly impossible for a normally-constituted person (i.e., a non-sociopath) to leave behind the web of moral convictions, even if that person is a determinist. In this way, by arguing that moral and determinist convictions can coexist in the same person, PFS undermines the libertarian argument ...
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