There is no flaw in my response. When you are trying to evaluate how likely it is that some hypothesis accounts for your evidence, you must factor in the prior probability of the hypothesis. But the prior probability of your hypothesis depends on your background knowledge. How often times, in general, are such explanations as the one you propose, true?
This is actually totally basic Bayesian reasoning about evidence, hypotheses, and probabilities.
Note that your response would also undermine any sort of deeper mechanism to explain the fine-tunedness of the fundamental constants. In fact, your response would invalidate the very notion of explanation.
How so? All my response is doing is pointing out that postulating a hypothesis with extremely low priors to account for some data, has the danger of still ending up with a very unlikely hypothesis even after the data is included. It is possible for the data (the evidence to be explained) to be so good that it overcomes this extremely low prior. But youād have to actually try to derive the prior of the postulated hypothesis first before you could say. You can then plug your numbers into Bayeās theorem and calculate the posterior of the hypothesis being true, given the evidence.
With respect to your hypothetical scenario of a hypothetical planet explaining some pertubations on the trajectory of another planet, itās prior probability given your background knowledge depends on how often times before similar such explanations have turned out to be true. I think we can agree that generally speaking, it has much more often been the case that bodies exuding gravitational attraction on each other result in pertubations of their orbits, than it has bee the case that āchanceā was.
Iāve never ever heard of it being the case that āchanceā was the real explanation for how some planet moved, and only ever heard of it being the case that other bodies with mass pull on them and affect their orbits, the hypothetical planet hypothesis must have very high prior probability, certainly much higher than āchanceā.
One objection you could be making here with respect to the God hypothesis is that we donāt know the priors. We do not have previous experience, we do not have background knowledge, about how often it has generally been the case that Gods pick values of the fundamental constants like the ones we observe. Hence the prior is basically uknown. But the same is also true for the prior probability of some deeper explanation for the physical constants. Again we do not have any background knowledge that tells us how often it has generally been the case that physical constants are explained by some deeper physical structure. Hence the probability of that is also unknown.
But then that completely undermines the fine-tuning argument for the existence of God, because none of the relevant probabilities are known that would allow us to determine how likely it is that ānaturalismā, ātheismā, or some other hypothesis is. It is not enough merely to say that the values can take some particular range N and then calculate the probability as being 1 in N, since it still doesnāt tell you whether that which causes the values to obtain is somehow biased towards any particular one.
The fact that I have a die with 6 sides doesnāt mean the die has a 1 in 6 chance of landing on any particular one. It could be weighted.
