A common question that atheists ask of theists is what could convince them that there is no god. Theists tend not to have a great answer to this question — atheists take this to signal victory! But I don’t think that this is a great question and it’s not a problem that theists or atheists don’t know what would change their minds.
In science, it makes a good deal of sense to know what would change your mind. After all, scientific theories make precise predictions about the world. Thus, if you don’t know what would falsify your theory, that’s a problem for the theory — it can’t make accurate predictions about the world if there’s no prediction that could ever be inaccurate.
But the same is not true of philosophical theories. I’ll provide a few examples.
Modal realism is the idea that everything that’s metaphysically possible actually happens. The reason that people believe in modal realism is because they think that it explains various concepts — modality, causality, properties, and so on. I have no idea what would convince me of modal realism — it doesn’t make empirical predictions. Thus, my answer to what would convince me of modal realism is ‘some convincing argument, plus my objections being refuted.’
Utilitarianism says we should maximize aggregate well-being. I have no idea what would convince me that utilitarianism were false — once again, it makes no empirical predictions. Thus, once again, the answer would be ‘the balance of arguments favoring disbelief in utilitarianism, rather than belief in it.’
But whether god exists is a philosophical question. While there are some things that should raise our credence in a perfectly good god existing — Jesus returning for example — if on philosophical grounds we think that god almost certainly doesn’t exist, it would be reasonable to suppose that, even if Jesus returned from the dead, problem of evil considerations prove there’s no truly perfect god. There is merely a very powerful entity playing magic tricks — or maybe aliens.
Thus, like with philosophical topics, my answer to the question of what would convince me that there is a god would be ‘having my objections refuted, plus having good reasons to believe in god.’ We should stop thinking about god as a scientific theory, and thus reject the requirement of explicit falsification.
Oh Please. If Jesus Christ came back down from Heaven and started turning Wine into Water you would find a way to get yourself into heaven, even if that meant believing in God.
I’ve thought about the question of empirical facts that could falsify ethical theories.
If utilitarianism is true, intelligent and rational people should be persuaded by it. I think this would apply to alien civilizations as well. If aliens were utilitarian, I would be more confident in it. If they weren’t, I would be less confident in it. The same goes for AI.
Similarly, if we are actually in a simulation, I would feel less confident that moral realism is true because this world is filled with suffering. It could be a simulation of myself but I suffer at times as well. I would think if simulated minds were possible and utilitarianism were true, I feel like I should be in a happy simulation, not a world filled with suffering. The probability of finding oneself in a suffering world or as an observer who suffers should be vanishingly small across time. Utilitarian overlords should’ve created tons of happy simulations. I guess this argument depends on what you think the right way to reason about observer selection effects is.