I came across this article by Richard Bushey, called If Atheism Is True, It Follows That Atheism Is False. On the chance that it might be a worthwhile argument, I thought I'd see what Bushey has to say, because I continue to hold open the possibility that I will someday find the elusive theistic argument that is convincing to someone who is not already convinced. I must admit, though, that my expectations are low. The most sophisticated theistic arguments by highly educated philosophers may be logically valid, and certainly seem to be unassailable in the eyes of other theists, but still fall short of the mark in changing the mind of someone who isn't already a theist. The main reason for this is that they all seem to depend on premises (whether stated explicitly, or simply assumed) that cannot be accepted by a non-believer. To accept premises of this type would be tantamount to conceding that God exists before the argument is made.
Bushey's argument, based on its title, appears to be an example of proof by contradiction. With the goal of proving proposition T (theism is true), the basic form of the argument should be to first assume the opposite of that (proposition A - atheism is true), and then follow the implications of that assumption until it results in a contradiction. In this way, proposition T would then be shown to be true. This is a valid form of logical argument. Let us now look more closely at how Bushey's argument proceeds. Here is how he summarizes it:
(Premise one) if God does not exist, true propositions do not exist.Bushey nominally follows the form of the argument by contradiction, but only in the shallowest manner. We would expect this argument to start with the assumption that atheism is true and make valid logical steps from there until a contradiction is reached. But that's not really what it does. Bushey does not follow the logical implications that would be entailed if atheism were true, but instead asserts a theistic assumption from the very beginning of his argument. Specifically, he assumes that there are no true propositions without God, and the entire argument is based on that theistic assumption.
(Premise two) True propositions do exist.
(Conclusion) Therefore, God exists.
At this point, I should state my own understanding of the terms 'proposition' and 'true', since Bushey fails to define them for the purposes of this argument. The relevant definition of 'proposition' in Merriam-Webster is: an expression in language or signs of something that can be believed, doubted, or denied or is either true or false. A proposition is a statement about some state of affairs that can be true or false. 'True' is defined as: being in accordance with the actual state of affairs. Truth is correspondence to objective reality. And these definitions are not based on any assumption of theism or atheism, and should be acceptable to anyone, but I'm not sure Bushey agrees with that.
With regard to the existence of propositions, Bushey holds the Platonic belief that propositions are objects that have an ontic existence apart from any mind. That defies the definition of the word, which involves the expression of a statement. In my own opinion, if there are no minds, there is nobody making any kind of statement which could then be judged to be true or false. Propositions are statements about some state of affairs, as the definition of the word says. Nevertheless, as long as there are people who can make such statements, I have no problem agreeing that propositions exist.
On the issue of truth, Bushey assumes by virtue of his theistic assumption that an atheist must be a "relativist". And by that, he means truth is relative to the person or mind who beholds some proposition. A proposition could be "true for you, but not for me". Note that he does not provide any support at all for his first premise. He simply assumes it. The bulk of the discussion for his argument is devoted primarily to showing the absurdity of relativism. The thrust of all this is to show that true propositions do exist, in support of his second premise.
Incidentally, his concept of relativism seems to be rather muddled. In arguing that science would be undermined if all was relative, he uses the example of DNA evidence that doesn't change. On this point, Bushey seems to be heading down a dangerous rabbit hole. Objective reality is not relative to any mind. However, the state of affairs can change over time, and evidence can change over time. So there may indeed be cases where evidence must be evaluated in relation to a timeframe. Bushey's point about relative truth is lost here because he makes the false assertion that the truth of a proposition cannot be relative to time. Consider the proposition "The age of the sample is determined to be 100 years". Clearly, the truth of that proposition is dependent on when it is asserted. But that's not the same thing as relative truth in the sense that it was discussed above, and Bushey doesn't seem to recognize that. This is indicative of his muddled thinking.
I'm not sure where Bushey gets this notion that relativism is entailed by a world without God. The only real example I can point to is moral relativism, which holds that moral judgments are based on the opinion of the individual and his society, and there are no moral truths grounded in God. It would be mistaken to extend this idea of relativity to factual truth or logical axioms, yet that appears to be exactly what Bushey has done. He has built a caricature in his mind of the absurdity of a world without God. But this notion that "all would be relative" is not based on any logical entailment of the simple assumption that atheism is true.
At any rate, given the caveat I duscussed about the ontological status of propositions, no reasonable atheist would disagree with Bushey's second premise. There's no contradiction between atheism and the existence of true propositions. The big problem with his argument is in his first premise, which is patently false. If Bushey wants to state that there can be no truth without God, he needs to provide some supporting evidence or argument for that, and he has not done so. He has provided no reason whatsoever for a reasonable person to think that his first premise is true. It is nothing more than a blatantly theistic assumption. And it is only this theistic assumption that leads to contradiction - not any genuine logical entailment of the simple assumption of a world without God. So this argument turns out to be just another example of concluding what the theist assumes from the outset. The thing that stands out about Bushey's argument is just how blatant his theistic assumption is.
But Bushey shouldn't be too ashamed of his utter failure to make a convincing argument for God. After all, he's doing the same thing that the greatest theistic philosophers do, although many of them manage to hide their assumptions more effectively. But they are all convinced that these arguments are airtight. I sometimes wonder how they can be so blind to the theistic assumptions they make in their arguments. I can only presume that theism is so deeply embedded in their thinking that they can't separate it from their logical reasoning. Bushey can't imagine a world without God, so he just assumes that such a world must be absurd. It never occurs to him that it might actually be a logically coherent world.
This is the common thread of theistic arguments. They can't separate their arguments from their theistic beliefs, and so their arguments are riddled with theistic assumptions. I'm still waiting to hear that elusive theistic argument that is free of any such assumptions, and still logically valid. But I doubt I ever will.