Friday, February 06, 2009

Case study: William Lane Craig vs. Bart Ehrman

In my ongoing discussion about the need for experienced debaters in the atheist camp, a theist named MrFreeThinker linked to a debate between William Lane Craig and Bart Ehrman, in which he asserts that Bart Ehrman was "pwned." In particular, MFT says:

Bart Ehrman made some mathematically poor claims where he equivocated between intrinsic probability and specific probability with regard to miracles. W.L. Craig was able to use Baye's theorem to show how his reasoning was mathematically fallacious. Ehrman was unable to counter Crag's claims but made some backhanded ad hominems later on saying that Craig would be laughed at if he tried to bring his calculations on miracles to any secular university. W.L. Craig then pointed out that philosophers such as Richard Swinburne (a eminent philosopher of science at Oxford University) had also made similar calculations it was a moment of sheer pwnage.

(On a side note Swinburne's calculations on the probability of Jesus' Resurrection and God's existence are available in his books "The Existence of God" and "Resurrection of God Incarnate")

After reading the debate transcript, I have to agree that Ehrman made some missteps. But I don't think they're the ones the MFT thinks they are.

Let's start with the topic being debated. Right now I'm a bit fixated on the issue that theist/atheist debates are routinely set up with fixed, bogus, and stacked resolutions. THIS debate proposed to settle the following question:

Is There Historical Evidence for the Resurrection of Jesus?

Sigh... here we go again. As I keep saying, theist debaters perpetually count on setting up debates with a loaded topic, so that the unbeliever loses before the debate has begun.

So what's wrong with this topic? Yet again, it allows the theist side to play semantic games with definitions. What qualifies as "historical evidence" for the resurrection of Jesus? I think a naive atheist would assume that this means there is "sufficient, compelling, and persuasive evidence" that establishes the resurrection of Jesus. Fine, if you have a sympathetic audience. But you don't. You never will. So here's what Craig's obviously going to do: he's going to declare that any claim by anyone that indicates Jesus was resurrected counts as "historical evidence." And he wins! Why? Because he's right!

Just like "theory," "evidence" is a word with numerous meanings depending on how it's applied. So if Craig can find one person, from any point in history, who is willing to say "Jesus was resurrected," he's got evidence. Is it good evidence? Duh, of course not. But it's evidence. By the same standard, I could easily lose a debate asking me to prove that there's no historical evidence for Galactic Overlord Xenu. And the Salem Witch Trials provided all kinds of evidence (read: other people's testimony) proving that those women were, in fact, in league with the devil.

Ahem, Bart, I believe the topic you actually meant to debate was this: "Was Jesus resurrected?" Simple. No frills. When you stepped into this loaded topic, you gave Craig a free pass to "win" just by throwing out enough stuff to allow for the vaguest possibility that Jesus was resurrected. You awarded yourself the burden of proof, requiring yourself to demonstrate conclusively that there is no evidence of any kind, good or bad.

So if nothing else, I want to thank MFT for bringing up yet another perfect illustration of my point. Now let's move on to the substance of the debate. I'm not going to go through the entire thing. For now, I just want to focus on the specific case this argument from probability that he brought up.

From where I sit, all I see is Craig doing what creationists always do. He throws up a bunch of obfuscated equations on the board, counts on his audience not knowing enough to understand what the argument is, slips in gigantic assumptions about the natural world, and declares victory.

Obfuscated equation: check.

Pr (R/ B&E) = Pr (R/B) × Pr (E/ B & R) /
[ Pr (R/B) × Pr (E/ B & R) ] + [ Pr (not-R/B) × Pr (E/ B & not-R) ]

What value does that equation add to the credibility of Craig's actual argument? None whatsoever. It's a time filler, and it awes a lay audience who are expected to treat monstrous equations as magical incantations.

When you strip away the filler, Craig finally gets around to framing his actual argument, which is this:

"In order to show that that hypothesis is improbable, you’d have to show that God’s existence is improbable. But Dr. Ehrman says that the historian cannot say anything about God. Therefore, he cannot say that God’s existence is improbable. But if he can’t say that, neither can he say that the resurrection of Jesus is improbable. So Dr. Ehrman’s position is literally self-refuting.

But that’s not all. Dr. Ehrman just assumes that the probability of the resurrection on our background knowledge [Pr(R/B)] is very low. But here, I think, he’s confused. What, after all, is the resurrection hypothesis? It’s the hypothesis that Jesus rose supernaturally from the dead. It is not the hypothesis that Jesus rose naturally from the dead. That Jesus rose naturally from the dead is fantastically improbable. But I see no reason whatsoever to think that it is improbable that God raised Jesus from the dead."

That's it. It took approximately five pages and three slides to say that. Five pages of scribbled equations, smarmy insults, cute little nicknaming conventions, and a whole pile of hand-waving. To obfuscate those two simple sentences.

And when you strip the argument down to those two sentences, the argument sucks. It's basically "Jesus could rise from the dead, because God can do magic!" Hey, wait a minute, I thought that was a big part of what we were arguing about in the first place. But Craig just asserts that this is true, and doesn't support his implied belief that magical events are happening all the time. Instead of backing up this claim, he deftly covered it up in those five pages of completely tangential empty academic masturbation.

This is endemic to creationist arguments. Kirk Durston does that too. Michael Behe does it a lot. What these debates have in common is that they use tons of math as a way of befuddling the audience, lulling them into thinking "I have no idea what that guy is saying so he must be smart." Then they have a hook to bring the argument back to the audience's reality. They make a spurious connection between the hook and the math, and then "therefore God exists."

They do this all the time. It's their main tactic.

The thing about math is, it does actually mean something specific, but it's impossible to look up or pore over the details during a live debate. It's also long and it's boring, and they're counting on the audience to gloss right over the equations and assume that the hook is a correct summation of the math.

Okay, so since we know this tactic is going to come up repeatedly. How do we deal with it? I haven't settled this in my own mind, but I have some ideas. First of all, the math is guaranteed to be a smokescreen. There's a place for equations in a scientific journal, or a class full of students who are studying the topic, but if you're trying to persuade an audience of mixed education, it's a sure bet that the intention is to obfuscate rather than explain.

So blow past the math. It's important to watch like a hawk for the moment where the apologist explains what his REAL argument is, and make a snap judgment about whether this argument stands up on its own. You can't study the math or verify it during the debate, so you can assume that (1) it may well be full of lies and phony inferences, and (2) the audience will have no idea if it isn't. So above all else, do not waste time actually addressing the equations.

At any rate, atheists already have a perception problem of being overly nerdy, being concerned with "science" and "evidence" and whatnot. I think a little verbal kung fu is in order, i.e., using your opponent's strength against him. Don't just skip the math... ridicule it. That may sound kind of mean, but pay attention: William Lane Craig is kind of a dick anyway. He resorts to slides with labels like "Ehrman's Egregious Error" and "Bart's Blunder."

Hell, I think it wouldn't hurt to have a slide ready that says "Craig's Cretinous Calculations." And then, fill the page with truly irrelevant equations. Put up the freaking Pythagorean Theorem, or an expanded quadratic equation. Make a joke out of it. The audience will crack up if they realize you were prepared all along to hit Craig with his own nonsense. Odds are that they were probably feeling uncomfortable already because Craig was making them feel stupid, so it should be easy to get them laugh with you. And then, boil down his argument to its unsupported essence, and nail it.


But I digress. We were discussing how Bart Ehrman did. Well, MrFreeThinker, I'm willing to concede that he didn't do all that great. This is right in line with what I keep saying: apologists win debates because they are good at performance art. Ehrman wasn't prepared to act like a circus sideshow attraction.

But don't think that means I'm ridiculing Craig when I say "circus sideshow." That's what an apologetics debate is. Bart should have been prepared to do performance art, and if he can't win at that game then he isn't prepared to debate.

As for Richard Swinburne, I couldn't care less what he thinks. Craig pulled him up because he was name-dropping. Preceding this comment, Ehrman said this:

"I have trouble believing that we’re having a serious conversation about the statistical probability of the resurrection or the statistical probability of the existence of God. I think in any university setting in the country, if we were in front of a group of academics we would be howled off the stage."

Ehrman shouldn't have said that. You know why? Because he should have known that for any crazy belief in the world, there probably exists some crackpot academic who will support it.

So yeah, I guess I'll sort of give Craig the point for his name drop. What he proved was that the correct phrasing is:

"In any university setting in the country, if we were in front of a group of academics we would be howled off the stage... unless, of course, one of them happens to be Richard Swinburne."

31 comments:

  1. @Kazim
    Craig's point was that Ehrman was equivocating between 2 kinds of probability.
    And it isn't only Craig that thinks that. He talked about the book "Hume's Abject Failure" (written by agnostic btw) about how Humean skepticism doesn't stand up to probability calculus.
    lol@ "Craig's cretinous calculations"

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  2. Craig is a snarky SOB. I looked at his blog right after the debate - I think it was the only time I went there - and he and his acolytes were going on about how he'd "defeated" Bart, how Bart just doesn't get it, etc.

    Debate isn't about determining truth; it's about winning at all costs. For evangelicals, winning means validating their absolutely abhorrent belief system.

    I'm not sure that the atheist will necessarily garner sympathy from the audience by using his own methods of obfuscation, however. People in the audience have already chosen sides. The fundies just assumed Craig was right, because that's what they wanted to believe. If Bart had used math, they would have simply allowed their innate distrust of education to take over. They would have assumed he was wrong.

    Remember, these are the people who say, "Even if evidence for evolution exists, I will still refuse to believe it." They've made the subordination of evidence to faith the foundation of their lives. And they're proud of it; they see it as an asset, not a liability.

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  3. You should send this post to Richard Carrier, he's debating Craig on basically the same subject on March 18th.

    Although, Carrier might fare better as he is very familiar with Bayesian statistics.

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  4. But Dr. Ehrman says that the historian cannot say anything about God. Therefore, he cannot say that God’s existence is improbable. But if he can’t say that, neither can he say that [insert random bullshit] is improbable. So Dr. Ehrman’s position is literally self-refuting.

    *clap* *clap* *clap*

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  5. You might be interested in this video, from the final round of last year's national championships of the American Parliamentary Debate Association. (American parliamentary style does sort of take the best of both the LD and policy worlds. I think you'd like it.)

    http://www.parlidebate.com/recordings.php?id=185

    It's about whether an evolutionary biologist ought to debate a creationist. Not strictly an atheist/theist dichotomy, but it touches on a lot of related arguments.

    -Z from thoughtcounts.net

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  6. I saw that Carrier was going to debate Craig, and saw several posters say that Craig was a great debater. I can't see it. Craig is great at flinging poo and lies in abundance, and considering most of his audience is his followers, I guess that counts as a "win" to them. I have several of his debates, and have listened to them while driving to and from work, and have felt like putting my face through the windshield at the stupidity, illogic, and overwhelming suppositions that have no support that Craig uses.

    The problem (as you say) is that basically the atheist (or opponent to the fundy/creotard) tends to rely on rational arguments and evidence, while the fundy relies on showmanship and pushing bs as fast as they can. Pathetic, really, and it gives honest debate a bad name.

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  7. The problem (as you say) is that basically the atheist (or opponent to the fundy/creotard) tends to rely on rational arguments and evidence, while the fundy relies on showmanship and pushing bs as fast as they can.
    I think it tend to be the other way around. Craig tends to use reasoned arguments and many opponents try to use derisive appeals to ridicule or emotion (OMG teh bible has ZOMBIEZZZ) or circular reasoning( naturalism is true so miracles don't happen and miracles didn't happen because naturalism is true).Craig is good at calling out his opponents on these flaws.

    Carrier seems more versed in philosophy than Ehrman so hopefully he can avoid these flaws in reasoning.He also seems competent in debate. I saw a debate between him and Mike Licona on he same topic and was rather shocked at how he tried to present his own re-translation 1 and 2Corinthians to fit his theory.
    It should be a good debate nontheless.

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  8. Russell - I now have to go back and listen to NonProphets from last year. In one episode, you said something like "If a person says x, then he is probably an atheist." At the time, I was going to write to tell you that you were wrong. You have to look at the underlying probabilities to get the correct conditional probability. Since the probability of being an atheist is so low, the fact that 99% of atheists would say x does not mean that the a person who says x is probably an atheist. I have to go find what you were talking about to call you out on your earlier incorrect probabilistic example.

    For anyone interested, think of this example - an illness occurs with a frequency of 0.1% (1 in a thousand individuals get it). There is a test that is 99% accurate in diagnosing this disease. If your test comes back positive, what is the probability you have the disease? Only 9%.

    In a group of 100,000 people, we would expect 100 to have the disease. Of the 100, 99 would get a positive test, 1 would get a false negative. Of the 99, 900 without the disease, there would be 999 false positives. So there would be 1,098 people with positive tests, only 99 of whom - about 9% - actually have the disease.

    So now that Russell is expounding on probability, I have to call him on his earlier error.

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  9. Another great post. Thank you.

    Apologists for faith are a peculiar community, who seek to avoid or deflect criticism by creating smokescreens and slipping behind the obscure abstractions of higher theology or mathematical models. A mist-shrouded domain of long words, superfine distinctions and vague subtleties. Desperately seeking a position that cannot be clearly falsified.
    This is pure sophistry. Pathetic.

    If "complex" apologists think that the billions of religious adherents around the globe are just so because they have resolved complex mathematical equations or reached a plane of philosophical bliss then they are seriously misguided.

    Religion is not mathematics, theology or philosophy. It is the basic practise of ordinary people whose supernatural beliefs were inculcated as children. The overwhelming majority of adherents believe in something far more basic and traditional than any fanciful inventions of mathematics or theology.

    Think of densely forested hideaways where complex apologetics and theology relish in concealing themselves. The roots of which start from precisely the same place as plain and ordinary superstitious faith. Take an axe to the roots and it all comes tumbling down.

    I greatly enjoy the degree of sophistication the blogs and comments reach, but you know, sometimes you need only to just scratch beneath the surface to see just how vaporous some of the arguments are. Don't build on sand after all.

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  10. You have very deftly nailed the essence of Craig's argument.

    More importantly, you have highlighted a fundamental limitation of Bayes' Theorem: it is probative only to the extent that the prior probabilities are actually known — not merely supposed. Another way of looking at Bayes is that it describes the relationship of evidence to prior skepticism. Craig's argument boils down to, "If you find the resurrection of Jesus initially plausible, it will take very little evidence to persuade you it's actually true." Hardly profound.

    Craig's first comment regarding God's improbability is more telling. He claims fundamentally that neither the existence of God nor the resurrection of Jesus is falsifiable: there is no amount of evidence which could persuade the believer that either statement is false. The prior probability of God's existence and Jesus' resurrection is 100%, and Bayes' theorem always yields 100% for any evidence if you start with 100%.

    Plantinga is explicit on his position: he claims to show not that evidence or argument is or should be persuasive to the non-believer, but that belief in God is logically consistent and compatible with empirical observation, that theism is not irrational.

    Craig plays a more disingenuous game: He starts off saying the evidence should be persuasive to the non-believer, but supports this position by showing that theism is not irrational for the believer.

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  11. He claims fundamentally that neither the existence of God nor the resurrection of Jesus is falsifiable: there is no amount of evidence which could persuade the believer that either statement is false.

    This is precisely my point - which is why I refuse even to engage them. That, and the fact that their belief system is the most despicable pile of manure ever devised - yet they think it's roses, and that we're too "inherently depraved" to perceive it.

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  12. Another way of looking at Bayes is that it describes the relationship of evidence to prior skepticism. Craig's argument boils down to, "If you find the resurrection of Jesus initially plausible, it will take very little evidence to persuade you it's actually true." Hardly profound.
    You totally mangle Craig's rebuttal.How it went was
    Bart: Historians can only deal with what is most probable. Miracles are highly improbable events so a historian cannot say that any one was the most probable
    Craig: Bart is being mathematically fallacious.Bart takes the intrinsic probability of miracles to be low. However according to Baye's theorem, we also need to take into account many other factors than the intrinsic probability of the event. Because there are so many other factors we can say the overall probability is high even if the intrinsic probability is fairly low.
    When Hume presented this argument centuries ago he did not have probability calculus. However Bart Ehrman does now and he has no excuse for his mathematical blunder.


    Craig's first comment regarding God's improbability is more telling.
    He was responding to Bart Ehrman. Bart Ehrman claimed that historians need to be agnostic about God and not say anything about his existence in their work.
    Craig pointed out that if (according to Bart)historians could not say anything about God, they could not say anything about the probability of God's existence or miracles, so Bart Ehrman's argument is self-refuting. (Craig is good at calling out flaws in reasoning)

    I don't think Craig was trying o confuse anyone, and I understood what he was saying. I'm sure most of the audience at least understood that there was more to calculating probability that Ehrman let on.

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  13. I agree with MrFreeThinker. Craig is using Bayes theorem as a Bayesian would use it, to modify beliefs based on evidence. Craig specifically says that the prior probability (what he calls the "intrinsic" probability) of the Resurrection is "terribly low" (bottom of page 16 in the PDF).

    What Ehrman needs to do is shut up and multiply, something which Craig conspicuously does not do. How likely is the evidence, given that the Resurrection happened? Let's be generous and say that we're 99% sure that if the resurrection happened, we'd have the evidence we do. How likely is that evidence if the Resurrection didn't happen? I don't think it's terribly unlikely: after all, even a Christian must suppose that other people's miracle stories were made up. But let's be a little generous. Suppose we think that there's a 1% chance that we'd have all these Biblical accounts if something other than the Resurrection happened. We need a prior of at least 1% for the Resurrection to get a posterior probability of more than 50%. That prior hardly seems "terribly low" to me. If we say the Resurrection is a 1 in a billion chance, we should modify that to make it about 100 times more likely after doing the calculation, but that still means it's pretty unlikely.

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  14. Gosh, maybe it's just the years of calculus, but it seems to me that trying to apply probabilistic reasoning to a process that isn't random, isn't common enough to have its frequency even hypothesized about, and has never been observed by anyone, is just mathematical wankery.

    Bart takes the intrinsic probability of miracles to be low. However according to Baye's theorem, we also need to take into account many other factors than the intrinsic probability of the event. Because there are so many other factors we can say the overall probability is high even if the intrinsic probability is fairly low.

    On what Earth can the overall probability of some improbable event be "high"?

    This is pure and unadulterated cargo cult science. Slapping long equations with more letters and symbols than numbers onto a chalkboard or projection screen is shorthand for "smart science person at work." Craig's doing it here, I've seen Frank Tipler do the same thing. Behe and Dembski are frequent offenders on this, too. It's a classic trick of TV and movies: the character writing or contemplating the really long equation on the board is the brainiac.

    Seems like the best option, if not necessarily the easiest, would be to follow through with the TV and movie trope. While the brainiac's contemplating Prop director's last theorem on the board, someone else walks by and corrects an error, or says "you forgot to carry the two," and either inadvertently solves the thing, or exposes the wasted effort.

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  15. George:

    Obviously it depends on what the claim is. I don't remember the particular show you're talking about right now, so I don't know what you mean by "x". I am, of course, very familiar with the apparent paradox that comes from the rare disease detection, but I don't necessarily think the two are comparable.

    First of all, the disease in your example is 0.1%, while atheism is 5-15%, depending on how loosely you define it. And without knowing what I said statement "x" is, I'm not sure how likely it makes someone to be an atheist. Obviously if the statement is "there is no god" then the probability is 100%. If it's "You shouldn't believe in things without evidence" it might be 50%. (Assuming, for example, that 100% of atheists would say this, while only 15% of theists would.)

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  16. Gosh, maybe it's just the years of calculus, but it seems to me that trying to apply probabilistic reasoning to a process that isn't random, isn't common enough to have its frequency even hypothesized about, and has never been observed by anyone, is just mathematical wankery.
    Please watch the whole debate. The proobability equation only came up in William Lane Craig's rebuttal. He was not making any positive points with it. Bart Ehrman made a mathematically fallacious Humean argument from the improbability of miracles. Craig used Baye's theorem to show that Ehrman's argument was mathematically fallacious.
    Craig himself said that he felt we should not apply probabilistic reasoning, but Ehrman tried to make an argument from improbability. Craig showed the egregious errors in his probabilistic argumentation.

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  17. Now I disagree with MrFreeThinker. Craig went part way to showing Ehrman's reasoning to be fallacious, and conspicuously avoided using real numbers, so failed to make his case using Bayes Theorem.

    What Craig effectively argues is that we should believe something we initially consider very improbably if we're given very good evidence of it which cannot be explained any other way. That's what Bayes Theorem says, when applied by a Bayesian (Tom Foss seems to arguing that probability is only meaningful in a frequentist way, but that's not what's wrong with Craig's argument: plenty of atheists are Bayesians). But Craig gets no further than saying that Ehrman could be wrong if there was very good evidence which etc. etc.

    If Ehrman comes up with other ways for the same evidence to occur, then Craig's argument fails, even if those ways aren't terribly probable (as long as they're not terribly improbable, as Craig says the prior for the Resurrection is).

    Bayes Theorem is not magic, it's just a way of quantifying beliefs and evidence. As a debating tactic, using it against a non-mathematician is equivalent to the famous Euler/Diderot exchange (which probably never happened), but that doesn't make Craig wrong, just a bit of a dick. What makes him wrong is the same thing that always made him wrong: other explanations are preferable.

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  18. Craig himself said that he felt we should not apply probabilistic reasoning, but Ehrman tried to make an argument from improbability. Craig showed the egregious errors in his probabilistic argumentation.

    I don't need to watch the debate to know that this is gobbledygook. Craig has no way whatsoever of showing that miracles are not improbable, mathematical or otherwise. The fact that you can't seem to articulate how Craig's math shows Ehrman to be fallacious suggests that you were baffled by Craig's bullshit.

    If Ehrman's making a Humeian argument, then I'm guessing he's going with the basic 'which is less miraculous: the miracle that's being reported, or the possibility that the reporter is lying or has been fooled' bit from "An Essay Concerning Human Understanding" (if I recall correctly). Nothing in Craig's quoted rebuttal or mathematical formula does anything to rebut that: it is still more probable that the people reporting on the resurrection were lying or had been fooled than that magic made a dead guy come back to life.

    I mean, Craig's rebuttal actually invokes magic as though it makes the resurrection more probable! Of course no one's arguing that Jesus came back to life naturally, that's a blatant straw man. The question is whether or not he came back to life at all, a proposition for which there is no credible evidence, and considerable evidence against--mostly, the simple fact that people don't come back to life.

    You know, if people came back to life periodically through unknown means, we'd be able to study that and at least play with numbers and assign some infinitesimal probability to the event. So far, all the data say that people who are dead and buried for three days aren't up and walking around when the weekend's over. In order to overturn that data, you'd need some pretty solid evidence.

    Which is, of course, where Hume was going with the whole point; the bit from "Human Understanding" was refined by Carl Sagan into "extraordinary claims require extraordinary evidence." Such evidence does not exist for the resurrection, and no amount of mathematical wankery can make the miracle more probable than the possibility that the reports are false. Any claim of probability, any claim of supernatural intervention, would require its own supportive evidence.

    I don't mean to suggest that I'm not open to listening to the debate; if I get a chance, I'll check it out. But from what I see here, I'm not impressed, nor am I the least bit interested to listen to Craig pontificate bullshit over a loaded topic.

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  19. Now I disagree with MrFreeThinker. Craig went part way to showing Ehrman's reasoning to be fallacious, and conspicuously avoided using real numbers,
    He didn't need to use real numbers. All he tried to do was show how many factors Ehrman was ignoring in his probability argument. In my opinion, he showed this quite clearly and so was effective.

    so failed to make his case using Bayes Theorem.
    He wasn't making any kind of positive case. He was showing how Ehrman's probabilistic argument fails.

    What Craig effectively argues is that we should believe something we initially consider very improbably if we're given very good evidence of it which cannot be explained any other way.
    Craig was not arguing any positive points with his equation. He said himself that he was using the normal "deference to best explaination" method that historians use. He just used the equation to show how mathematically fallacious Ehrman's points on probability were.

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  20. I don't need to watch the debate to know that this is gobbledygook.... I'm not impressed, nor am I the least bit interested to listen to Craig pontificate bullshit over a loaded topic.
    You didn't watch the debate and you didn't see the points that Ehrman made on probability that Craig tried to refute, yet somehow you still claim Craig was wrong?
    I'm not talking to you anymore. It's obvious that you made up your mind on who is right before you even heard of Craig.
    Hume's argument is not taken seriously by contemporary philosophers. Look up "hume's abject failure" on Google books if you are interested in seeing a critique.

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  21. You didn't watch the debate and you didn't see the points that Ehrman made on probability that Craig tried to refute, yet somehow you still claim Craig was wrong?

    Yes, I can. Because at the end of the day, even if Craig was right on the math (which, as others with more Bayesian experience have said above, he wasn't), he still has not justified his assumptions with evidence. He

    It's obvious that you made up your mind on who is right before you even heard of Craig.

    That's probably true; I'd heard of Craig before this, and I've read pieces by both of them. In my experience, Craig's M.O. is baffle-with-bullshit, and Ehrman's is careful analysis of the historical sources. But I've examined the evidence independently and have come to the opposite conclusion from Craig. Unless Craig pulls out some actual evidence during the course of that debate, his performance won't sway my position.

    Hume's argument is not taken seriously by contemporary philosophers.

    Argumentum ad populum and appeal to authority arguments are not taken seriously by any philosophers, nameless and contemporary or otherwise. Whether or not philosophers take it seriously has no bearing on whether or not it is useful or true.

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  22. Paul: Tom Foss seems to arguing that probability is only meaningful in a frequentist way, but that's not what's wrong with Craig's argument: plenty of atheists are Bayesians

    I'm not entirely sure that that's what I'm saying. I've spent the last hour or so reading up on Bayesian statistics, and realizing that I wasn't nearly as unfamiliar with the system as I thought I was. Still, I feel like I only know enough to be dangerous, so feel free to correct me.

    Anyway, based on what I've read, it seems that the only way to determine the prior probabilities that go into the equation is to gather the data and examine it in a fairly frequentist fashion--determining how frequently the event is observed to happen given various circumstances.

    Incidentally, I'd forgotten that I downloaded the PDF transcript of this debate something like a year ago when I first heard about it, and that it's been sitting mostly unread in my documents folder since then.

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  23. Hume's argument is not taken seriously by contemporary philosophers.

    That's funny; I knew a number of contemporary philosophers and philosophers-in-training who took it quite seriously. I guess you can find philosophers on either side of an issue. Who knew? I thought that they were all omnipotent fonts of truth, Spock-like logic machines that all spat out the same information and can thus be 100% relied upon as authoritative.

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  24. Um, well, gee... it looks to me like MrFreeThinker provided an example of ONE modern philosopher who didn't take Hume seriously. Is this guy the official sponsor of all the other modern philosophers, or what?

    No, actually that guy DID take Hume seriously, at least enough to write a long paper on why he disagreed with him. It seems to me that if it weren't taken seriously at all, he wouldn't have needed to respond to it.

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  25. The fact that you can't seem to articulate how Craig's math shows Ehrman to be fallacious suggests that you were baffled by Craig's bullshit.

    I did several times before. Even in the post above I allude to to mistake Bart makes.
    To put it simply. Baynesian theorem says there are several factors we consider to evaluate probability. Bart Ehrman only considers one factor (the intrinsic probability) and acts as if he has found the entire probability. He ignores all the other factors in the equation.
    Craig explains this.

    I think the debate was a clear win for Craig. Craig presented good arguments and historical facts. Bart Ehrman was unable to refute any of his facts or provide a better explaination for them than Craig did and resorted to an 18th century argument that has been discredited by probability calculus.

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  26. there is one fun way to refute the mathematical 'proofs'
    if you play around a bit with the equations that apologists present, you'll find that they are, in fact, magic equations - they can prove anything.

    You'll notice it at the Ehrman/Craig debate itself - at the end of 'math presentation Craig does a little math gimmick with the equation:
    'this part will be a very high number, this part very low and this will cancel out and therefore voila - here's the result!'

    you can perform the same gimmick with a different assumption, say, Jesus was gay - and it will still work! You can even choose a different topic - like Elvis is alive, or UFO abductions - whatever you think the audience would find ridiculous

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  27. The equation is lengthy in Craig's argument, however what it really boils down to is a Percent Error Calculation. Craig's next assertation is that in (x/(x+y))[x=probabiltiy(jesus rose miraculously), y=probability(jesus did not rise miraculously)] that you have to prove god does not exist to develop a good probability of whether or not he raised jesus...... this is false--> the best way to debate this would be to discuss the probability that god miraculously intervenes in earthly affairs--> this probability based on empirical evidence over the course of history is a resounding 0%--> i.e. atheist experience spoon experiment :), studies on prayer for hospital patients etc..

    Ta-ta-for now

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  28. I wouldn't say Ehrman 'lost' the debate per se though his 'performance' was flawed in several important respects.

    His biggest mistake, which Craig exploited, was a common one in "skeptic vs believer" debates, which is a misguided desire to demonstrate his respect for perspective of the believer. He blew it as soon as he made the accomodationist assertion that " historians can say nothing about the existence or non-existence of God". This is reminiscent of Gould's talk of science and religion as "separate
    magisteria" or the oft heard accomodationist saw that "science can say nothing about the supernatural". Ehrman's very interesting personal journey from Christian fundamentalist to agnostic as a direct consequence of his study of Christianity from the perspective of an historian is itself dramatic evidence that one can indeed draw conclusions about the existence or non-existence of God from a study of the historical record.

    But having conceded this at the outset, he set himself up for Craig's rhetorical traps. As usual, Craig failed to persuasively sell his arguments, rather, he elites rhetorical fireworks to essentially tell Ehrman "Ta, ta, ta! You've already given up your right to say anything about God!"

    He does this sort of thing all the time, which thrills those already in his choir and bores everybody else. I think Ehrman actually DID attempt to point out that Craig's argument involving the Bayesian probability of a supernatural ressurection was fallacious because it simply assumed the existence of God (the Biblical God no less), but he didn't do it very well and it came across sounding like an ad hominem attack (i.e. "if you spoke of a mathematical probability of the resurrection based on the probability of God's existence before an audience of academics they'd laugh at you" or some such). It also could've been interpreted as a knock on those in attendance, and it's doubtful anyone realized the point he was trying to make wrt the Bayesian probability of a supernatural resurrection.

    I also thought it odd that Ehrman,, in another

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  29. [Oops - excuse typos in prior post!]

    I was in the process writing that I also found it odd that Ehrman, a self described agnostic, in what was ostensibly another accomodationist move, said that he thought theology was a legitimate mode of acquiring knowledge, especially inasmuch as it was clear in the context in which he said this that he was not referring to theology in the dispassionate, academic sense (as per, say, the study of extinct creeds or comparative religion) but to Craig's theology of the believer.

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  30. "Apologists for faith are a peculiar community, who seek to avoid or deflect criticism by creating smokescreens and slipping behind the obscure abstractions of higher theology or mathematical models. A mist-shrouded domain of long words, superfine distinctions and vague subtleties. Desperately seeking a position that cannot be clearly falsified. This is pure sophistry. Pathetic."

    I'm sorry but this is transparent, subjective, poorly-observed, intellectually-vacuous rhetoric.

    If there are arguments in Christian apologetics that are fallacious, then you simply refute them with formal logical arguments. Coping responses of this nature make a compelling case for one's own broader philosophical illiteracy.

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  31. Yay, another theistic post full of empty insults and no content!

    ReplyDelete

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