Radical Skepticism is Delusional

I had a lovely weekend arguing with undergraduates and alumni at my debating group’s annual alumni banquet.  And there was one argument in particular that seems relevant to the topic of this blog.  Over dinner, one alum was talking about his upbringing in a Christian Science church and was summarizing their bizarre theology.

Essentially, Christian Scientists think all evil is delusion.  God created a perfect world, and we must resist any illusion that suggest to us that the world is flawed.  This is why Christian Scientists are anti-medicine; treating a disease means you’re buying into the false idea that disease exists.

We had some fun trying to figure out the logical consequences of this bizarre premise.  Satan clearly had no place in Christian Science worldview, but how did one account for the Fall?  Moreover, how do you account for the existence of the delusions themselves?  They seem like an unambiguous evil that unambiguously exists (albeit subjectively).

Later on in the dinner, one of the other atheists at the table got into an argument with most of the rest of us about which standards of proof are appropriate for different claims.  Someone pulled out the “How do you know your mother loves you?” line of questioning.  It tends to go like this:

Q: Does your mother love you?
A: Yes.

Q: How do you know?
A: She tells me so and her actions back it up.

Q: How do you know she’s not tricking you?
Q: How do you know she has a genuine subjective feeling of love for you and isn’t acting according to societal norms or evolutionary imperatives?
Q: How do you know your mother exists?
Q: How do you know you’re not a brain in a vat?

At some point during this series, the atheist at the table gave up, bit the bullet, and declared himself agnostic with regard to his mother’s love and his own existence.  Which was not the result any of us were going for.

As a last ditch effort to undo the damage we’d done, I pointed out, “Look, we thought the Christian Scientists were ridiculous for disbelieving in evil, but you’ve done them one better and have disavowed evil, good, and everything in between.”  Before dessert was served, he was tentatively endorsing the idea that morality was objective, but still seemed a lot more comfortable in his position of radical doubt.

This was a prime example of valuing abstraction over the world.  Once you’re in a fight, it’s easy to prefer the defensible, circumscribed schema to one that actually has content and bears some resemblance to the world in which we live.  It’s easy to declare yourself a radical skeptic and claim you have nothing to defend while you skewer your opponent for every gap in their philosophy, but it’s cowardly and counterproductive.  Atheists should declare themselves as something more than atheist.

In my ideal religious debate format, I’ve stuck epistemology right up front.  Rip the band-aid off the wound and maybe you won’t have to play such a crippling defense for the entire rest of the fight.

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  • Tom

    So, what exactly do you recommend that the atheist do when the topic turns to epistemology? (And apparently, you think it should begin with epistemology.)

    The theist can say something like what William James said in The Varieties of Religious Experience. Here’s a paraphrase and expansion: ‘No one can provide a non-circular argument for trusting in any distinct source of evidence, so there’s nothing in principle ultimately wrong with trusting in faith (or revelation, religious experience, etc.). But since faith-revelation-religious experience support theism over atheism, theism is more reasonable, at least for many or most epistemic agents.’

    What should the atheist say, and can what she says be fit into the limited time of a debate? (Justifying foundationalism, if possible at all, would seem to take several hours at least, and might at least lose your audience’s focus or interest.)

    Building upon the above argument, of course, the theist can appeal to non-epistemic reasons for belief: ‘You should be a theist because, although the evidence is strictly neutral (see above), theism has many practical benefits.’

    • As a theist I don’t see how this should unsettle the atheist.

      He can simply note that the part about nothing being wrong with trusting in whatever doesn’t follow. Even if there can be no non-circular evidence for trusting a source of evidence that doesn’t mean there can be no evidence against trusting a source of evidence, because a trustworthy source of evidence should not prove things we already know to be false by it or other trustworthy sources of evidence.

      Then he says what he always says: Contradictory religious experiences by adherents of different religions, your God ordered evil things, dragon in the garage, yada, yada.

      • Tom

        Well, they don’t even need to appeal to religious experience in general; they can just appeal to their own. And so far, the atheist can’t say anything to bar that, can she?

        In any case, there’s no obvious non-circular way to argue that we should trust reason. In turn, there’s no non-circular reason to say that all contradictions are false, and so contradictions between faiths won’t be a problem.

        • Daniel A. Duran

          “Well, they don’t even need to appeal to religious experience in general; they can just appeal to their own. And so far, the atheist can’t say anything to bar that, can she?…there’s no non-circular reason to say that all contradictions are false.”

          Well, tell them they are not infallible and mock them if they suggest otherwise. Just because we cannot know propositions are true without begging the question in the end it does not follow all propositions are equally compelling.

          • Tom

            Thanks for the reply. I’m still not sure why the theist can’t make the case that at least all justifications of evidence sources are equally compelling. Here’s a quick argument:

            Suppose that a ‘metajustification’ is a justification of an evidence source. (It’s “meta” because the evidence source itself is normally what does the justifying of individual propositions.)

            (1) All metajustifications are ultimately question-begging.
            (2) No question-begging (meta)justification is any more epistemically rational to accept than any other question-begging (meta)justification.
            (3) Therefore, no use of an evidence-source is any epistemically more rational than any other use of an evidence-source.
            (4) Therefore, no criticism of religious experience as an evidence source should be compelling (at least unless it comes from religious experience, itself).
            (5) Religious experience overwhelmingly supports some form of theism.
            (6) There are no ultimately compelling criticisms of religious experience as an evidence source. (Partially justified from (4).)
            (7) Therefore, theism is at least prima facie justified.

            (There are a few enthymemes, of course, but you get the idea.)

            In simpler terms: if the atheist uses reason or empirical observation to criticize religious experience, the theist can just say that ultimately, the atheist’s metajustification for reason or empirical observation is no better than the theist’s metajustification for religious experience. This is a more technical way of expressing the ubiquitous “everyone makes a leap of faith” claim.

            I can imagine challenging the inference from (1) and (2) to (3) above, or challenging (2) itself. But I think given the plausible lemma that some beliefs are justified, those can be supported too.

        • As long as the theist also credits other sources of evidence the atheist can use them to imply personal religious experiences aren’t reliable. Known human susceptibility to illusions, equality with other people, whatever.

          As to your second paragraph, if your opponent denies the law of non-contradiction you indeed have no further argument against that. But then with most audiences you won’t need one because very few people would be willing to jump down that rabbit hole. So you just point out how this would justify literally everything and maybe note that nobody believes it honestly. Your biggest problem will be spreading that over however long the speech is supposed to be.

          • Daniel A. Duran

            Tom, a person might *say *that all evidence is equally useless or useful to establish a point and so we must make a leap of faith. But and you and I know such person does not actually *believe* so; he will find some sorts of evidence more persuasive than others whether he admits to it or not.

            You can tell him that his position contradicts the bible; after all, the bible is filled to the brim with purported miracles that serve as evidence of the providence of god. You can tell him that the bible repeatedly points to the order of the universe as evidence that god is omnipotent and so on. You can tell him that his religious experiences are extra-biblical since they do not appear or are supported by anything in the bible (all interaction with god in the bible is presented as physical), etc.

            Does he insist in religious experience as the only reasonable course of action? Well, his loss. You can bet that people in that debate will be more impressed by your arguments than his.

          • Tom


            I guess I would still worry that many theists will be perfectly willing to abandon the law of noncontradiction when it comes to God Himself. They’d be wrong to do so, I think, but that doesn’t mean they won’t. In any case, I think trying to find ways in which religious experience is unreliable might be the better response, although it’s difficult to imagine how the atheist can make that case stick when most theists will take themselves to be in fairly normal, non-experimental conditions when they feel that they are having religious experiences. (They won’t have parts of their brain stimulated with electrodes, e.g.)

            But this still leaves aside the broader point the theist can make, which is that without a pretty detailed epistemology, the theist can always hold that there’s nothing in principle wrong with forming her beliefs in theism without evidence at all. (This is a version of what philosophers call ‘Reformed epistemology.’) If the atheist wants to argue that theism is somehow irrational or unjustified, the atheist will run up against a wall here. (The theist will typically dress her position up with some talk of not being able to make sense of reasoning or knowledge at all without theism, or finding the belief in God so obvious or default reasonable that it would outweigh any arguments against it, and so on.)


            The theist might say that all intuitions, feelings, or perceptions are default reasonable, claiming that that’s the only way for any justification to get off the ground. Then, once again, a very simple religious experience story ends up reasonable. You’re right that this may not sit well with Bible believers, but in my opinion, the smart theist won’t rest too much on the Bible either.

            So the worry is not that religious experience is supposed to be the only reasonable course of action; the worry is supposed to be that perhaps all experiences (or even all beliefs) will end up ‘default reasonable,’ on pain of global skepticism. Then at the very least the theist will maintain that she is justified in her position. (See especially the last paragraph of my response to Gilbert.)


            I guess the point I’m trying to suggest here is that delving into epistemology may not be very helpful for the atheist; it may allow the theist at least to escape any positive criticism of the way she forms her beliefs, since all ways of forming beliefs are open to huge criticisms: they’re circular.

            Again, the theist may say: ‘It is obvious to me that God exists. I can’t imagine Him not existing. To persuade me that this belief is irrational, you would have to give me an argument with premises more plausible than theism is for me. But nothing could be as plausible as theism, especially since you don’t have any non-circular justification for the premises of your objection to my theism.’ I guess it’s playing defensively, but many debates are about whether it can be reasonable to be a theist, right?

          • Emmanuel

            As to your second paragraph, if your opponent denies the law of non-contradiction you indeed have no further argument against that. But then with most audiences you won’t need one because very few people would be willing to jump down that rabbit hole.

            I think there is a case for denying the law of the excluded middle and proof by contradiction. Scientific empiricism is founded on evidence for claims. Many mathematical details are worked out with proof by contradiction. How are we to apply mathematical results gotten through proof by contradiction to the real world which requires evidence as opposed to a coherence argument against the non-existence of something?

            Further, the idea that there is one correct opinion is founded on the principle of the excluded middle. Denying it would seem to imply that self-consistent systems should be given equal weight as legitimate systems of thought.

        • Daniel A. Duran

          “The theist might say that all intuitions, feelings, or perceptions are default reasonable”

          Level up with us now Tom, which theists has ever said that all beliefs are prima faciae reasonable? Why should we assume that they will start doing it now?

          • Patrick

            Tom is advancing an argument that is, at least in part, similar to that of the presuppositionalists, and similar to that of Alvin Plantinga and his followers. Neither says precisely what Tom is saying, and the concepts have been mixed and matched a bit, but the ingredients are there.

            I’ve certainly heard theists claim that intuitions should be treated as default reasonable, unless a defeater exists for them.

            And I’ve certainly heard theists make the rhetorical move that Tom is making: utilize the infinite regress problem of epistemology to claim that all beliefs are ultimately “circular,” then claim that this makes theism reasonable. Its similar to what Stephen Law calls “going nuclear” in his writing on intellectual black holes. Rhetorically level everything down to equally stupid, and then you’re not unusually stupid in comparison.

          • Tom


            Indeed, Patrick is correct below that some of these sort of moves are sometimes called ‘presuppositionalist’ or ‘transcendental’ arguments for God’s existence. But there are really five largely independent theistic epistemology lines going on here that I want to discuss. We can divide them into positive projects and negative projects, based on whether they’re primarily designed to show that theism is positively reasonable, or instead that it’s at least not positively unreasonable.

            Positive projects:

            (1) Presuppositional or transcendentalist arguments hold that it is a necessary condition of thought, rationality, knowledge, epistemic justification, etc. that one believe in God or theism, or at least deny naturalism. Plantinga has advanced an anti-naturalism argument that bears some resemblance to these approaches, essentially this: ‘If our epistemic faculties are the result of evolution, they’re less likely to be accurate (instead of merely survivally fit) than if they were designed by God. So naturalists have less reason to trust their epistemic faculties than theists do.’

            (2) Reformed epistemology: Theists, particularly in the Calvinist tradition (see especially Plantinga), sometimes argue that belief in God is ‘properly basic’: justified even without any inference from any other belief. They might claim that there’s nothing particularly unreasonable about a very broad form of theism like this, and that everyone takes some beliefs to be foundational anyway: justified but not by any inference from any other belief.

            (3) Religious experience: Following in the tradition of William James, the theist might argue that a very basic religious experience seems to support some form of theism, and that there’s no very good evidence that most religious experiences are generated in epistemically suspect ways.

            (4) Phenomenal conservatism: This is not strictly a theistic approach; it’s much more general and has been defended recently by philosophers like Michael Huemer. The idea is that it’s epistemically rational or reasonable to take appearances or seemings at face value until you have a positive reason to doubt them. The theist, then, can try to maintain that her beliefs are default reasonable until there’s a positive reason to doubt them, and argue that there’s no such reason, at least when it comes to a fairly minimal theism.

            Negative project:

            (5) Epistemic egalitarianism would be the position that ultimately, no non-circular way of justifying beliefs is any better than any other from the perspective of epistemic justification. If so, then the theist’s religious experience, faith, or foundationalism will be at least some prima facie evidence.

            Overall point:

            I’m suggesting here that talking about epistemology may lead to broadening the belief-sources that the atheist has to admit are unjustified, which only really hurts the atheist.

  • Brandon

    I’m unclear on why the question whether one knows their mother loves them isn’t best answered by stating that present evidence indicates that it’s the most likely explanation, but granting that there’s other possibilities as well. That doesn’t seem like radical skepticism to me at all.

    • Katie

      Right. You can simultaneously be “agnostic” about whether your mother truly loves you, or even claim that there could be no truth to such a question (as I would), and believe that such a belief is nevertheless a reasonable and intelligible description of reality as we experience it. It seems to me that certainty is a very silly standard, and it can be extremely frustrating when others demand it of you, or claim to have met it themselves. It seems to me like that’s what made Leah’s friend dig his heels in.

      • leahlibresco

        Wait, what do you mean there’s no truth to that question?

        • I would be interested in reading Katie’s response (it may differ radically from my own), but if I were to say something like that (and I might), it would be that love isn’t necessarily an essential thing that exists inside a person (a position to which I have no access) but instead a relation constituted by all of the things one would cite as evidence for it. Love is a verb denoting actions, not a noun denoting an affective state. So to ask whether the love that I think exists is really love is like asking whether rain falling on us was really rain, or whether it just had all of the accidents of rain.

          Of course, I don’t actually think love is only a verb; I think it is also a noun denoting an affective state, and I think that is an important difference. (Behavioural models are great and all until the cognitive model predicts something the behavioural model would have to call anomalous.) However, if my mother’s actions were consistent enough times and in varied enough circumstances (recalling your recent post on free will, Leah), I might suggest that the odds of the cognitive model failing are sufficiently low that I can simply work with the behavioural one.

          • Katie

            Ha! That’s actually pretty much the opposite of what I would say.

            I’m disinclined to take seriously the proffering of behavior as “evidence” of an affective state. This will sound incredibly pedestrian, but assuming your mother acts in the way that she does for a reason (i.e. the consistency of her behavior is owed to a cognitive constant), it could be a whole bunch of other reasons. (E.g. There is enormous social pressure on mothers to conform to a particular model of selfless care-taking, so much that one woman, Ayelet Waldman, who said that she loved her husband more than her children, was savaged by other mothers. “Let me at her,” yelled one woman in the audience at a talk show.) That we understand typical mothering behavior as being born of love, as opposed to a sense of obligation or insecurity or mere habit, is an arbitrary semiotic decision made by a particular contemporary collective. The reality is that the circumstances under which this behavior occurs aren’t varied enough for us to have come to that conclusion rationally. Where are the controls? How would you even control for things like social pressure, convenience, or habit? I’m not sure that even the real thing, the affective state that is love, would survive such radical changes in circumstances.

            I suppose you could define love purely in behavioral terms, as an observed relation, without assuming an underlying cognitive constant, but this seems like the height of absurdity to me. It would amount to one using one’s consciousness to “reason” about the nonexistence thereof, a classic cogito problem.

            My position is essentially that a brain in a vat can experience affective states just fine and everyone should be able to agree that its consciousness of, say, love is sufficient to make that love real. Now, if you really push me, I would tell you that I don’t know that I am not a brain in a vat. (In fact I think that to ask that question assumes an ability to entertain things outside my cognition, which is incoherent.) But a brain in a vat nevertheless reasons about the evidence it perceives and constructs expectations about an external reality that might then be either confirmed or disappointed. My cognition is fundamentally structured in a way that assumes that I do not get to choose what I perceive, that I am compelled to believe true things because they will be true regardless of whether I or anyone else think them. I am comfortable talking about the truth of propositions that can be subject to that process, and these are necessarily evidential matters. If you define love purely as an affective state, there is no evidence and no evaluation: it is real the moment you feel it. The proposition “I love X” can’t be true because it can’t be (found to be) false.

          • Katie, I don’t particularly disagree with you. Perhaps I didn’t make it clear: I think that the word “love” refers to multiple concepts. If I said that I believed my mother loved me and was prepared to give evidence for it, then I would be talking about love as an observable relation, and so if I said the question about how I knew was nonsense, I’d give the response above. If I said that I thought my mother loved me, I might well be talking about her affective state of love, but since that’s unaccessible, I would not be willing to commit to such a thing for much the same reasons you outlined. (Anyway, I wouldn’t be convinced that societal pressure wouldn’t actually generate something that feels like love…and if it feels like love, it is really love. As you said, “it is real the moment you feel it.”)

  • Interesting approach, I personally agree with the conclusion that to not defend a viewpoint is cowardly. One of my least favourite arguments is one involving the rejection of objective reality, which seems to happen during discussions with people who base most of their beliefs on belief, which is obviously a circular argument, “I believe it, therefore this is my reality.” we all have leaps of faith, God, the missing link, the Oort cloud, essentially everybody believes in stuff that isn’t subject to regular standards of proof, that is invisible. All beliefs are based on the interpretation of facts, it is a fact there are fossils, it is a fact that these represent creatures that once lived. Evolutionists & creationists each interpret these facts in different ways, somebody is right, somebody is wrong. The type of circular argument just mentioned has the result that nobody is wrong. Rather than each persons view being recognised as a mere interpretation, subject to correction upon improved knowledge, the interpretation becomes the created reality, resulting in your brain in the vat. I believe people should be sceptical, but it is nice to see that other people who are capable of the extreme modes of it can also see that it is indeed cowardly & delusional.

    • Brandon

      we all have leaps of faith, God, the missing link, the Oort cloud, essentially everybody believes in stuff that isn’t subject to regular standards of proof, that is invisible.

      This is complete nonsense. The “missing link” is a trope that doesn’t have any valid basis in reality; there’s no such thing.

      So far as I know, no one has any faith in the existence of the Oort cloud; it’s hypothesized based on physical evidence, and is a hypothesis that will be confirmed or rejected on the basis of further evidence.

      • When I pose the question, “where do long period comets come from?” to just about anyone who doesn’t simply say, “I don’t know” the answer is “the Oort cloud.” I would say that expresses a certain amount of belief in it. It is a hypothesis, correct, but that doesn’t prevent people from believing it exists. their belief would be based on faith. You say it is based on physical evindence, & a theist would maintain that their belief in God is based on the physical evidence that complexity doesn’t happen by accident. Physical evidence or not, the conclusion that there is a creator, or an Oort cloud still takes a leap of faith.

        Let me clarify the “missing link.” I should have used th term “common ancestor between human and great apes” there is no physical evidence supporting the existence of such a creature, that is, there are no fossils, so it is a missing link, which is thus not a trope. The only evidence provided is genetic theory, which can’t be tested beyond the confines of a species, because you have to have a known family relationship to start with. We can’t say we know that apes & humans are related, use that to prove genetic theory, then use genetic theory to prove they are related, obviously this would be circular reasoning. If we can’t test it beyond the confines of a species then we fall on logic to see if we can make a leap beyond the species, that leap is based on affirming the consequent, in which case the burden of proof would be on the evolutionist to prove that the only possible reason for similar genetics is a family relationship, I’d be interested to know what proof we have that this is definitely the case. Thus, the existence of a a common ancestor between humans & great apes is a leap of faith, based on interpretations of events. To some this is a reasonable interpretation, to others not so much.

        I’m sure you knew exactly what I meant by “missing link” so I have to wonder at your approach, was picking on a small issue of word selection the best you had?

        • leahlibresco

          I don’t know exactly what you mean by ‘missing link.’ We’ve found non-sapiens fossils that appear to be related to us, but apparently that doesn’t suffice for you. I assume you’re picturing something like:


          but if I managed to fill that spot in with a specific hypothetical fossil (let’s call it Humape)


          I suspect you’d object that there are now two gaps to fill:


          • Brandon

            Oh no! Progress in evolutionary biology just creates more gaps! We’re doomed!

        • Brandon

          their belief would be based on faith. You say it is based on physical evindence, & a theist would maintain that their belief in God is based on the physical evidence that complexity doesn’t happen by accident. Physical evidence or not, the conclusion that there is a creator, or an Oort cloud still takes a leap of faith.

          Let me grant, for a moment, that there is physical evidence for a deity, even though there certainly isn’t at present. Even granting this, there’s an enormously key difference here between the beliefs you’re describing – someone who has tentatively settled on the Oort Cloud explanation is likely to happily change his stance if evidence arises that there’s a superior explanation. He/she does not have faith in the hypothesis they’ve accepted, it’s just the best explanation they’re aware of at the moment. By contrast, the vast bulk of theists openly state that conflicting physical evidence with their beliefs isn’t relevant, as they have faith.

          There are many, many common ancestors between humans and other apes. I don’t think you’re well informed about that particular topic, and I’m not picking on a small issue; I’ve not seen anyone that is well informed about hominid evolution use the phrase “missing link” in recent years.

          • “Many, many common ancestors, based on what evidence are they said to be common ancestors? What are these many common ancestors, perhaps I am mis-informed, or perhaps the fact is that there is another creature out there that really is just another creature, not an in between.

            If someone could provide me with a better explanation for the immense complexity in the universe than intelligent design, I’d gladly accept. For the numerous physical laws that Big Bang would violate to have actually occurred, it hardly seems likely that something like that could’ve happened without any help. So I feel I’m doing the best with the information available on this subject, & I’m quite willing to change my views should better information come up.

            I’m not that closed minded, I was brought up believing evolution, but the more I examined the issue, the less likely it sounded. I think one of the major problems in the world is that most people won’t budge on their viewpoints, evolutionists included, & as Micheal Creighton pointed out, nobody knows what happened, just that it did. I must ask, how do we then know it happened? It would be interesting to see an evolutionist apply the same critical awareness to the question, “did evolution happen?” As people apply to various religious views when they are trying to debunk them. Truth is, few systems would survive that level of critical awareness, science; logic; maths all have serious flaws.

  • The atheist that defaulted to radical skepticism seems to think that all doubt is equal. I would say there is a 99.99% chance that my mother loves me. I would say there is a 0.1% chance that Christianity is true. Even though there is a level of uncertainty in both, the probabilities for both are not equal.

    This radical skepticism is the counterpoint to a theist who claims that we all have faith in something, therefore faith in the Christian worldview is on equal footing as a scientific worldview. This is obviously incorrect because the probability of Christianity being true isn’t equal to the probability that philosophical naturalism is true.

    The analogy I always use in these cases to explain the reductio ad absurdum of this logic is Russian Roulette. If one had to play a game of Russian Roulette and had to choose between two revolvers — one had one bullet chambered out of six and another revolver had five bullets chambered out of six — which one would you choose? The radical skeptic atheist and the “all faiths are equal” theist both have the confused logic of thinking that both probabilities are the same (i.e. 1/6 is equal to 5/6) and throw up their hands and say it doesn’t matter since it’s all faith and/or all uncertainties are equal.

    Obviously, 5/6 is not equal to 1/6, so having faith in the Bible is not the same as having faith in the scientific method or the doubt that you have about whether your mother loves you or not is not the same as the doubt about whether god exists or not.

    • I would say that mathematically, there is a 1 in 100 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 chance that the universe happened accidentally. Either something made the universe, or something didn’t, these are the chances nothing did it. So I don’t see atheism as being based on mathematical probability.

      The flip side is that the chances imy parents met and had me is less than 1 in 106 312 500 000 000 000 000 000 000 000 000 000, obviously I was born. The chances of each earlier generation working out in my favour increases, due to the reduction in population as we go further back, but those probabilities must be multiplied together to work out my probability of having been born. So, the chances of my grandparents meeting & having my parents is less than, 1 in 64 312 500 000 000 000 000 000 000 000 000 000, for each of my parents. This figure would have to be squared, to get the probability for both parents, & multiplied by the chances my parents met & had me, the calculations I used here would then have to be repeated for the next generation back, & so on, right back through the evolutionary history of our species, back to the chances that life just happened.

      The probability of life having just happened is probably incalculable, since we actually don’t know that life is. Chemically a corpse, freshly killed by a blow to the temple would chemically resemble the living body prior to the blow being administered, so we really don’t know what makes a bunch of inanimate molecules come to life, so how can we estimate the mathematical probability that life just happened.

      Once we have calculated all this, we still need to multiply it by the chances the universe just happened (the original figure given here). Ultimately, the chances that any of us arrived at the point that we could have read this blog & engaged in this discussion are ludicrous. Congratulations, you made it, despite the odds.

      Again, I must point out that either something made the universe, or something didn’t, this would be the thinking one would have to estimate the chances of their existence in the case that nothing did it. Please send me the odds that something did it, I’d be interested to know how one arrives at the chances of it being really small, because I wouldn’t know how to calculate the odds that there is no designer. Like I said, I don’t think atheism is based on mathematical odds.

      • Apologies, for the typos. I do need to correct the last paragraph to state that it should read, “I wouldn’t know how to calculate the odds that there is a designer.” Obviously the odds I was calculating were for a “no designer” scenario.

      • Heh. If you want to play the probability game, I’m game 🙂

        Again, I must point out that either something made the universe, or something didn’t, this would be the thinking one would have to estimate the chances of their existence in the case that nothing did it. Please send me the odds that something did it, I’d be interested to know how one arrives at the chances of it being really small, because I wouldn’t know how to calculate the odds that there is no designer. Like I said, I don’t think atheism is based on mathematical odds.

        I actually don’t know what a hard and definitive probability is for theism vs atheism, but you’re going to have to go a long way to go from generic deism to the Christian god, probability wise.

        I actually don’t like to talk about atheism vs. theism. I think naturalism vs supernaturalism is a more concrete distinction. Let’s say that someone had no dog in whether naturalism or supernaturalism were true and had no prior bias towards either. So they’d start out agnostic, giving a 50% chance to naturalism and a 50% chance to supernaturalism. Let’s do that too. Where do we go from there?

        The supernatural is basically the belief in disembodied minds of some sort. Let’s run with that.

        For one, the prior probability of disembodied minds is extremely low. Every single instance of minds that we have are instances of minds with bodies. So the ratio of embodied minds to disembodied minds is something ridiculous like 7 billion+ to a not known to exist 1, in the case of some creator god.

        Second, disembodied minds break every single law of thermodynamics. How do disembodied minds get their energy? Where does the unused energy consumed by these disembodied minds go? How do they interact with the world? Sight and sound, just to pick two senses, are wholly physical phenomena. Something that wasn’t physical would have no means of hearing anything; and if it did, then there’s a whole lot of money to be made by tapping into this ability and letting us hear things in space. As far as I’ve encountered, every person who posits some supernatural beings has always described them as perpetual motion machines. And we have zero instances of perpetual motion machines in the universe. This, again, lowers the prior probability of disembodied minds.

        To get around these questions, you’d have to posit some other laws of physics which, I’m afraid, doesn’t actually help. Since these other laws of physics haven’t been demonstrated and are only being posited to prop up an already low probability hypothesis, this lowers the probability of it being correct even more since it is literally ad hoc. And since these other laws of physics haven’t been demonstrated, there’s a low prior probability for this ad hoc other-physics, which needs to be true in order to validate the other two questions.

        Why this is, is because stacking untested hypotheses lowers the initial probability exponentially. Like if you wanted to bet on getting 3 heads in a row in a coin flip, it’s .50 * .50 * .50. Each coin flip needs the previous coin flip to be heads, similar to even entertain the existence of disembodied minds needs some other laws of physics which then allows for perpetual motion machines, which then allows for us to even have any means to look for disembodied minds.

        There’s a lot more to this, but I don’t want this to be long. Suffice it to say, it looks like probability favors naturalism over supernaturalism.

        But hey. Maybe there really is some disembodied mind that created the universe. I don’t know. The problem with the Christian god, however, is that the guy can do anything since he’s all powerful. Arguments for design and fine tuning actually argue against the Christian god because he can do anything. A design argument only works for a limited god, since the design argument assumes a god that had to look up what sort of universe would produce human beings and then design the universe to follow those specs.

        The Christian god, since he’s all powerful, has no need for specs. So a non all powerful god is favored over an all powerful god as a contender for some supernatural creator. And this can even be explained using probability.

        This is Bayes’ Theorem: P(H | E) = P(E | H) * P(H) / [P(E | H) * P(H)] + [P(E | ~H) * P(~H)]

        P(H) is the prior probability. In this case I’ll restrict it to the hypothesis that an all powerful god, like the Christian god, made the universe. P(E | H) is the probability of our universe and its very specific laws of physics being what they are given that an all powerful god created the universe. P(E | ~H) is the probability of our universe given some other hypothesis (deism, Greek pantheon, some other non-all powerful god, atheism, the Matrix, Scientology, etc. etc.).

        In order to solve this, we need to know P(H), P(E | H), and P(E |~H). I think that my critiques of disembodied minds applies to this all powerful god, so I think the prior probability for this all powerful god is low. All powerful gods are pretty extraordinary anyway, and when something has a “high probability” this is just another way of saying mundane or normal. Low probability is another way of saying extraordinary.

        The next thing is to try to find out what P(E | H) is. I have no clue, but most theists would assume that it’s something high, like 99% or something. The problem with this is that P(E | H) is one half of a probability coin. The other half is P(~E | H) — not to be confused with P(E | ~H) — this is the probability of having, in this case, some other universe given that an all powerful god created the universe. P(E | H) + P(~E | H) = 100%. So if one claims that P(E | H) is 99%, then they are in effect saying that P(~E | H) is 1%. Or, they are saying that their all powerful god couldn’t create any other universe besides this one. But this isn’t the type of all powerful god that anyone believes in. What’s to stop an all powerful god from making the speed of light 3 * 10100 km/s? Or use perpetual miracles to keep us alive on Mercury? Or Pluto? This god has no restrictions, and since “any other universe” is included in P(~E | H), it looks like the vast majority of the probability is weighted on that side. P(E | H) is infinitesimally low.

        What is P(E |~H)? Again, I don’t know. But certainly there is some other hypothesis that can only explain this universe and can’t be used to explain any universe imaginable. Any hypothesis that restricts itself to only being able to explain this universe or one or two other universes would be favored over an all powerful god hypothesis.

        P(E | H) / P(E | ~H) is the Likelihood Ratio. You can see from the link that a likelihood ratio that is lower than 1 favors ~H. In this case, since an all powerful god hypothesis can explain anything, the probability that it explains this universe to the exclusion of other universes imaginable is, like I said, infinitesimally low. It would be a lot lower than some hypothesis that limits what it can explain. Like I said, some non-all powerful god would limit the type of universes it could explain. Maybe the Roman pantheon created the universe :).

        But then we come back to naturalism vs. supernaturalism. And to ignore the prior probability that I argued for above would be a base rate fallacy, even if the probability of the universe given some other non-all powerful god (i.e. supernaturalism) is higher than the probability of the universe given naturalism. If people ignored the base rate (or prior probability), then we could throw people in jail for winning the lottery. Since winning the lottery given that you cheated is higher than winning the lottery given basic luck.

        • I unfortunately have not been active online, & deleted my original reply, but since your argument sounded compelling, I felt it deserved a reply, so here, is a revised version of what a deleted.

          You possibly weakened your argument by bringing up naturalism vs supernaturalism. Your definition of the supernatural is flawed, & damages most of your argument as a result. The supernatural is simply that which is not governed by natural laws. The fact that we cannot examine the embodiment of supernatural beings doesn’t automatically mean they are disembodied. Angels, and as a result demons, are supernatural beings that are described with bodies, biblically anyway. Disembodied minds, as far as a separation of body and soul (at death) goes, does express an existence of a disembodied mind, but that isn’t the basis of the supernatural, and is, strangely enough, not biblically supported.

          If we consider this, your argument regarding “known” disembodied minds simply comes down to testability. Many people claim to have interacted with dead souls and the like, and although most rational individuals would write such events off as delusional, but this is faith based, since we can’t test their assertions. If these supernatural beings, disembodied or not, were testable by naturalistic means, then they would not be supernatural, and thus your figure of 7 000 000 000 to 1 (possible) isn’t valid, on the grounds that it is based on reducing the supernatural to naturalistic reasoning.

          Your argument regarding physical laws, of which many are violated by Big Bang, falls into the same trap. The physical laws we work by are naturalistic, & thus any being prone to them wouldn’t be supernatural, so this really doesn’t help you. While I’m on this subject.

          Stacking of untestable hypotheses seems to be based on the idea that we can test the supernatural by naturalistic means, which I’ve covered. While we on the subject, the idea that everything can be explained by naturalistic terms is not only a untested hypothesis, but an untestable one. Funny how positivism is based on an untestable assumption, thus all atheism, which has very low odds, is based on the untestable hypothesis, that everything is testable, which would reduce the odds that it is valid. As would Rees’ six numbers reduce the chances of atheism being correct.. The initial probability I gave for the universe just happening was based on the idea that everything just fell into place, but it didn’t consider that the natural laws would have had to be perfect. Gravity for example, if changed slightly, would alter the course of all universal history, even in a short earth scenario. The odds of atheism suddenly falls drastically below what I originally mentioned. I won’t go into the other untestable hypotheses that are used to base atheism on, since the odds are already so low.

          I detest intelligent design as a proof for God, simply because it’s heavily flawed. I think intelligent design is a good explanation for complexity, but it is based on the assumption that there is a designer, & therefore can’t be used as a proof for that creator. This said, you reduce intelligent design to one argument, while I’ve heard various arguments, so the term “the intelligent design argument” is like saying “the theory of evolution states”, and then using all discredited parts of Darwin’s book to make an argument, it’s bad form. Intelligent design broken down is that complexity can only be explained by a designer, that’s all the various ideas have in common.

          Ironically, the best argument is that an almighty creator chose the particular design he did from infinite possibilities. The irony is, that it doesn’t give odds for the existance of such a deity, but odds of chosen activities. This is a problem since the discussion was regarding atheism and odds of this universe, this is the one that is here, what are the odds nothing made it. The best argument against can only be made on the assumption that something made it, which doesn’t favour atheism.

          If we assume the only valid assertion is the one regarding the choice of universe, which in itself isn’t necessarily based on random choice, then the odds, are about the same that gravity was accidentally favourable. These odds are infinite, putting both groups in the same situation, belief is not based on odds, but on faith. In the case of a theist, faith in a creator, and in the case of an atheist, faith in the oxymoron that all hypotheses are testable, which is itself untestable.

          If one was going to test the odds of Christianity is valid would have to be based on the veracity of Biblical prophecy, which is interpretable. This would obviously still require a leap of faith in the method of interpretation. The one point we can agree on is that modern Christianity is probably not true, if one believes the Bible is the Word of God, one can’t just ignore the idea that the Bible does support doctrines like separation of body and soul, or the immortality of the soul, and many other popular doctrine.

          I still feel, and I’m not agnostic, that the only odds based belief system when it comes to the supernatural is agnosicism, which would be supported by the odds that we don’t know everything, and therefore can’t make a judgement on knowledge of the supernatural.

          Thanks for the reply, though, it certainly gives me things to think about, and is the best I’ve ever had on this issue.

    • To be fair, you were arguing science vs Christianity, not atheism vs theism, or agnosticism. I still always find it interesting that it’s always science vs Christianity, when in most cases it’s evolution vs Christianity. Creation scientists, for example Prof Walter Veith, a prof in zoology who spent many years teaching evolution, argue that they are also using science. So couldn’t it be argued that it’s one scientific viewpoint vs another one.

    • Steven Richards

      “the probability of Christianity being true isn’t equal to the probability that philosophical naturalism is true”

      Are you claiming to be omniscient? If not, how could you possibly “know” that you’ve evaluated all the evidence?

      • Non sequitur?

        Or maybe we should apply Occam’s razor and not multiply the entities and purposes without cause. Such a maneuver pretty handily handles your problem of induction.

  • Patrick

    Well, that was kind of mean. You read Less Wrong, you should know that the Cartesian definition of knowledge is dumb for evidential matters.

    • leahlibresco

      Yes, and if someone brings it in a conversation as binding on religious claims, I’m going to push it to it’s logical, absurd conclusion.

  • deiseach

    Q: How do you know she has a genuine subjective feeling of love for you and isn’t acting according to societal norms or evolutionary imperatives?

    But I thought neurobiology had proven that subjective feelings of love are evolutionary imperatives!

    “But of course the words and deeds of other people are simply environmental influences that can affect our brain molecules. That’s how love begins.” – Jerry A. Coyne, professor in the Department of Ecology and Evolution at The University of Chicago (from his article about the illusion of free will, the one where Chet rebuked me for doubting that Professor Coyne had laid out a plausible argument.

    Your mother may think she loves you, but she’s only acting under the influence of neurotransmitters released under the evolutionary pressure of maximising reproductive success by ensuring mothers were interested in taking care of offspring until those offspring were viable (by which is meant, capable of taking care of themselves independently).

    • Alex

      Huh? Why can’t it be both? Why are love and neurotransmitters mutually exclusive? I see no obvious contradiction between thinking that my mother loves me and is also acting due to the neurotransmitters in her brain.

      To give an analogy, playing the piano consists of producing sound by striking the keys on a piano in a certain configuration. To say that I am playing Fur Elise, and to describe the movements which my fingers are carrying out, convey exactly the same information (if you which which keys to press with which fingers then you could play Fur Elise) yet we acknowledge that both are occurring. Yet you don’t hear anyone giving the argument that I am somehow “not really” playing the piano because I am really “only pressing down certain keys in a certain configuration”. Both are true!

      More generally, just because A can be described in terms of B does not mean that A isn’t “real”. Speaking of which I have no idea what you mean by “real”. Would you mind helping me out?

  • Emmanuel

    I agree that radical skepticism is delusional. I don’t think a lot of thought has gone into the logical commitments required to carry out these debates. As an example, Mathematics went through a period of shaken confidence in the late 19th century with the discovery of non-euclidean geometries. Which one was correct? Eventually it was decided that there wasn’t a particular correct one. They were all merely self-consistent. This line of inquiry somewhat terminated in Godel’s completeness and incompleteness proofs of first order logic with equality. The emphasis was shifted from finding the structures which accounted for our naive conceptions of mathematics (think Kronecker’s statement that god only created the integers) to the study of axiomatically defined structures.

    Given that there are consistent logical systems without the law of the excluded middle, higher and first order logics, and so on, it seems odd that no one says what logic they are using. Everyone just says they have logic and reason on their side. Whatever that means.

  • Huh. Leah, how does this compare with your being impressed with Doubthat’s argument for nihilism? I see these as somewhat related, perhaps erroneously.

    One seems to say, But how do you really know X (all the way back to whatever your first premise/foundation is)?”

    The other seems to say, “But how do you really know that life has meaning (all the way back to whatever you think forms the basis for meaning)?”

    Perhaps the two join up somewhere and just merge at a node on the common ancester, “epistemology.” Your tone seemed slightly ridiculing of this fellow who was talked out of his surety about reality, but you seemed genuinely troubled about Doubthat’s proposition. Is my take accurate, or is your response to both of them something like, “Yes, and what if we are brains in a vat? What will you do differently?”

    I rather like this take on the subject of “truth.” If actions have provided you with good reason to believe your mother loves you… accept it provisionally. While you perhaps can’t prove she does (she could be faking it, an alien in human form, etc.), until you have reason to discard it, you won’t. Engaging in this type of mental exercise seems pretty useless from a practical standpoint.

    The person asking questions in these lines is clearly trying to ensnare and prove his awareness of philosophical gridlock on things like this. Just stop the discussion early and ask, “What would you like to achieve in this discussion?”