As, basically, an atheist, my response to the question ‘Is there an all-powerful god?’ is to ask: is that question actually meaningful? Is it akin to asking, ‘is there an invisible pink unicorn?‘, or ‘have you stopped beating your wife yet?’. To whit, a mu situation https://en.wikipedia.org/wiki/Mu_(negative) .
There are a lot of different types of question, and probabilities don’t seem to mean the same thing across them. Sometimes those questions are based on fuzzy semantics that require interpretation, and may not necessarily correspond to a possible state of affairs.
The possibility of a god existing doesn’t equate, to me, to seeing if a possible thing exists or not, but rather whether the set of concepts are in any way possible. This is a question about the very nature of reality, and I’m pretty sure that reality is weird enough that the question falls far short of having any real meaning.
Your comment made me realise that I skipped over the objection that the questions are too ambiguous to be worth engaging with. I’ve now added a paragraph to fix that:
To me, and presumably most LessWrong readers, the most obvious response to these questions is to dissolve them, or to at least try to pin the questioner down on definitions. And I do think that’s very reasonable. But in this post I want to put my (current) belief that “we can always assign probabilities to propositions (or at least use something like an uninformative prior)” to a particularly challenging test, so from here on I’ll assume we’ve somehow arrived at a satisfactorily precise understanding of what the question is actually meant to mean.
I think the reason why I initially skipped over that without noticing I’d done so was that:
this post was essentially prompted by the post from Chris Smith with the “Kyle the atheist” example
Smith writes in a footnote “For the benefit of the doubt, let’s assume everyone you ask is intelligent, has a decent understanding of probability, and more or less agrees about what constitutes an all-powerful god.”
I wanted to explore whether the idea of it always being possible to assign probabilities could stand up to that particularly challenging case, without us having to lean on the (very reasonable) strategy of debating the meaning of the question. I.e., I wanted to see if, if we did agree of the definitions, we could still come to meaningful probabilities on that sort of question (and if so, how).
But I realise now that it might seem weird to readers that I neglected to mention the ambiguity of the questions, so I’m glad your comment brought that to my attention.
There are a lot of different types of question, and probabilities don’t seem to mean the same thing across them.
There are definitely a lot of different types of questions. There are also definitely multiple interpretation of probability. (This post presumes a Bayesian/subjectivist interpretation of probability, but a major contender is the frequentist view.) And it’s definitely possible that there are some types of questions where it’s more common, empirically speaking, to use one interpretation of probability than another, and possibly where that’s more useful too. But I’m not aware of it being the case that probabilities just have to mean a different thing for different types of questions. If that’s roughly what you meant, could you expand on that? (That might go to the heart of the claim I’m exploring the defensibility of in this post, as I guess I’m basically arguing that we could always assign at least slightly meaningful subjective credences to any given claim.)
If instead you meant just that “a 0.001% chance of god being real” could mean either “a 0.001% chance of precisely the Judeo-Christian God being real, in very much the way that religion would expect” or “a 0.001% chance that any sort of supernatural force at all is real, even in a way no human has ever imagined at all”, and that those are very different claims, then I agree.
The possibility of a god existing doesn’t equate, to me, to seeing if a possible thing exists or not, but rather whether the set of concepts are in any way possible. This is a question about the very nature of reality, and I’m pretty sure that reality is weird enough that the question falls far short of having any real meaning.
I don’t understand the last half of that last sentence. But as for the rest, if I’m interpreting you correctly, here’s how I’d respond:
The probability of a god existing is not necessarily equal to the probability of “the set of concepts [being] in any way possible” (or we might instead say something like “it being metaphysically possible”, “the question even being coherent”, or similar). Instead, it’s less than or equal to that probability. That is, a god can indeed only exist if the set of concepts are in any way possible, but it seems at least conceivable that the set of concepts could be conceivable and yet it still happen to be that there’s no god.
And in any case, for the purposes of this post, what I’m really wondering about is not what the odds of there being a god are, but rather whether and how we can arrive at meaningful probabilities for these sorts of claims. So I’d then also ask whether and how we can arrive at a meaningful probability for the claim “It is metaphysically possible/in any way possible that there’s a god” (as a separate claim to whether there is a god). And I’d argue we can, through a process similar to the one described in this post.
To sketch it briefly, we might think about previous concepts that were vaguely like this one, and whether, upon investigation, they “turned out to be metaphysically possible”. We might find they never have (“yet”), but that that’s not at all surprising, even if we assume that those claims are metaphysically possible, because we just wouldn’t expect to have found evidence of that anyway. In which case, we might be forced to either go for way broader reference classes (like “weird-seeming claims”, or “things that seemed to violate occam’s razor unnecessarily”), or abandon reference class forecasting entirely, and lean 100% on inside-view type considerations (like our views on occam’s razor and how well this claim fits with it) or our “gut feelings” (hopefully honed by calibration training). I think the probability we assign might be barely meaningful, but still more meaningful than nothing.
As, basically, an atheist, my response to the question ‘Is there an all-powerful god?’ is to ask: is that question actually meaningful? Is it akin to asking, ‘is there an invisible pink unicorn?‘, or ‘have you stopped beating your wife yet?’. To whit, a mu situation https://en.wikipedia.org/wiki/Mu_(negative) .
There are a lot of different types of question, and probabilities don’t seem to mean the same thing across them. Sometimes those questions are based on fuzzy semantics that require interpretation, and may not necessarily correspond to a possible state of affairs.
The possibility of a god existing doesn’t equate, to me, to seeing if a possible thing exists or not, but rather whether the set of concepts are in any way possible. This is a question about the very nature of reality, and I’m pretty sure that reality is weird enough that the question falls far short of having any real meaning.
Your comment made me realise that I skipped over the objection that the questions are too ambiguous to be worth engaging with. I’ve now added a paragraph to fix that:
I think the reason why I initially skipped over that without noticing I’d done so was that:
this post was essentially prompted by the post from Chris Smith with the “Kyle the atheist” example
Smith writes in a footnote “For the benefit of the doubt, let’s assume everyone you ask is intelligent, has a decent understanding of probability, and more or less agrees about what constitutes an all-powerful god.”
I wanted to explore whether the idea of it always being possible to assign probabilities could stand up to that particularly challenging case, without us having to lean on the (very reasonable) strategy of debating the meaning of the question. I.e., I wanted to see if, if we did agree of the definitions, we could still come to meaningful probabilities on that sort of question (and if so, how).
But I realise now that it might seem weird to readers that I neglected to mention the ambiguity of the questions, so I’m glad your comment brought that to my attention.
There are definitely a lot of different types of questions. There are also definitely multiple interpretation of probability. (This post presumes a Bayesian/subjectivist interpretation of probability, but a major contender is the frequentist view.) And it’s definitely possible that there are some types of questions where it’s more common, empirically speaking, to use one interpretation of probability than another, and possibly where that’s more useful too. But I’m not aware of it being the case that probabilities just have to mean a different thing for different types of questions. If that’s roughly what you meant, could you expand on that? (That might go to the heart of the claim I’m exploring the defensibility of in this post, as I guess I’m basically arguing that we could always assign at least slightly meaningful subjective credences to any given claim.)
If instead you meant just that “a 0.001% chance of god being real” could mean either “a 0.001% chance of precisely the Judeo-Christian God being real, in very much the way that religion would expect” or “a 0.001% chance that any sort of supernatural force at all is real, even in a way no human has ever imagined at all”, and that those are very different claims, then I agree.
I don’t understand the last half of that last sentence. But as for the rest, if I’m interpreting you correctly, here’s how I’d respond:
The probability of a god existing is not necessarily equal to the probability of “the set of concepts [being] in any way possible” (or we might instead say something like “it being metaphysically possible”, “the question even being coherent”, or similar). Instead, it’s less than or equal to that probability. That is, a god can indeed only exist if the set of concepts are in any way possible, but it seems at least conceivable that the set of concepts could be conceivable and yet it still happen to be that there’s no god.
And in any case, for the purposes of this post, what I’m really wondering about is not what the odds of there being a god are, but rather whether and how we can arrive at meaningful probabilities for these sorts of claims. So I’d then also ask whether and how we can arrive at a meaningful probability for the claim “It is metaphysically possible/in any way possible that there’s a god” (as a separate claim to whether there is a god). And I’d argue we can, through a process similar to the one described in this post.
To sketch it briefly, we might think about previous concepts that were vaguely like this one, and whether, upon investigation, they “turned out to be metaphysically possible”. We might find they never have (“yet”), but that that’s not at all surprising, even if we assume that those claims are metaphysically possible, because we just wouldn’t expect to have found evidence of that anyway. In which case, we might be forced to either go for way broader reference classes (like “weird-seeming claims”, or “things that seemed to violate occam’s razor unnecessarily”), or abandon reference class forecasting entirely, and lean 100% on inside-view type considerations (like our views on occam’s razor and how well this claim fits with it) or our “gut feelings” (hopefully honed by calibration training). I think the probability we assign might be barely meaningful, but still more meaningful than nothing.