Showing posts with label Bayes Theorem. Show all posts
Showing posts with label Bayes Theorem. Show all posts

On the Christian Use of Bayes' Theorem, by JP415 and GearHedEd

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JP415:
I have an axe to grind with the way Craig, Torley, et al. used Bayes’ Theorem. It just seems like a diversionary tactic. During a debate, they break out an equation and say, “Our methods are objective! See, we’ve even got a math formula to prove it.” But when you look at the formula, you see that it’s stuffed with a bunch of unproven assumptions. They should know better. Maybe they do.
GearHedEd:
They do. Craig's entire career has been an effort to become a "respected Christian Apologist". He was already committed before he went to college. And none of the "priors" that they stuff into their Bayes' Theorem Machine are reasonable. It all comes from poorly evidenced claims in the Bible, and gets a "pass" because of where it was found.
JP415:
Yeah, it's like, "Given our prior background knowledge that Superman came from the planet Krypton, it's entirely likely that he could fly and shoot laser beams from his eyes." You could just put any old thing in there and get the results you want.
I think this analysis is basically correct, and I wish to comment further.

Quotes of the Day by Robert Conner

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I wish I could get Robert as a Team Member here at DC. Here's a quote for people who insist on following the latest Christian apologetic fad of trying to quantify unique miraculous claims in ancient history using Bayes' Theorem:
I don't know much about Bayes' Theorem, but I know it's August 1, 2017 and Jesus hasn't come back yet.
Here's another one highlighting the fact that faith is pretending to know what you don't know (think of the Sophists in Socrates's day):
Celsus repeatedly noted Christians boldly opine about all sorts of things they don't and can't know, and nothing has changed in the two millennia since. Jesusplaining Christians appear to think their convictions are some kind of "smart pill"--just witness the resident apologists who infest this site with their twaddle and who never cease to pontificate about everything from the ancient documents they read only in translation to particle physics to evolutionary biology.

On Keeping it Simple Stupid!

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One of the highest compliments I've received from my work was written by biblical scholar Robert M. Price. Of my contributions in the co-edited book God or Godless?he said I write "with unpretentious clarity, common sense, and broad but inconspicuous erudition." If anyone wants to see how high a compliment that is then look up each word he used. Let me highlight just two of his words, unpretentious and inconspicuous.

Unpretentious: I don't seek to impress my readers with Bayesian math, or the technical philosophical, theological, or scientific terminology, nor do I use the original languages of the Biblical texts much at all. I remember teaching my first philosophy class in 1985 at the College of Lake County, in Grayslake, Illinois. I lost about half my class because the students could not understand me. Yep, that's right. Having just come from a Ph.D. program at Marquette University I didn't know how to bring the information down to college students. Over the years I learned how to communicate to the average person. My goal is to keep it as simple as possible, and no simpler. The problem with this goal is that there are some readers who think I'm ignorant, for if I was smarter and better educated it would reflect in my vocabulary. Smart, educated people, it's assumed, use the nomenclature requisite with their educational achievements.

Inconspicuous: Even though Price says I have a broad erudition, it's inconspicuous or unnoticeable. It wasn't inconspicuous to him. But it's inconspicuous to others. The people for whom it might be inconspicuous would be the uniformed and ignorant, Price intimates. [Another equally high compliment of my work, which mirrors what Price said, was written by biblical scholar Hector Avalos.] It's extremely gratifying to know some important people say such things.

Dan Lambert Doesn't Think Bayesian Analysis Helps When It Comes to History

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Timothy and Lydia McGrew use a Bayesian analysis (or inference) to establish the resurrection of Jesus by a percentage of over 99%. Richard Swinburne uses it to establish that if God exists then Jesus was bodily resurrected from the grave by a percentage of 97%. However, by definition, even any given mundane (or ordinary, as opposed to an extraordinary) historical event is a unique one-of-a-kind event. And the events leading up to it, and follow it, are also unique one-of-a-kind events. So when looking to see if any given event took place in the past the historian must calculate the probability of the whole series of events, the ones that came before and after the event in question, even though all of them are unique one-of-a-kind events. How does one assign probabilities to them all when they are all dependent on each other? In one sense they are all improbable for that reason. To see this from a different perspective, consider an observer before any event takes place. All events in the future have an extremely low probability to them. No one could have predicted yesterday that I would be typing these very words today, you see. In any case, here is Lambert on Facebook taking about this subject:

Richard Carrier, James Lindsay, on the OTF

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Richard Carrier writes:
James Lindsay has been doing some great blogging on how to apply Bayesian reasoning to model John Loftus’ Outsider Test for Faith (or OTF).

Formulating and extensively defending the OTF is Loftus’ greatest contribution to the philosophy of religion and atheism. His best and most thorough treatment appears as chapter four in The Christian Delusion (a book I always recommend anyway as it contains lots of great chapters by great authors; and two by me). He is writing a whole book on it now. It should be out this year (I’ve seen advanced drafts and it’s good; I’ll blog it when you can buy it). The OTF is featured at Iron Chariots (which provides examples of looser expressions of the concept throughout history) and Loftus discusses it often at Debunking Christianity.

The basic idea is that you can only have a rational faith if you test it by the same standards you apply to all other competing faiths; yet when you do that, your religion tests as false as the others, and the same reasons you use to reject those become equally valid reasons to reject yours. Though this idea has been voiced before, Loftus is the first to name it, rigorize it, and give it an extensive philosophical defense; moreover, by doing so, he is the first to cause a concerted apologetic to arise attempting to dodge it, to which he could then respond. The end result is one of the most effective and powerful arguments for atheism there is. It is, in effect, a covering argument that subsumes all other arguments for atheism into a common framework. Link

Dr. James A. Lindsay's Definition of Faith

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Faith, he argues, is "a form of cognitive bias that tends to overestimate the probabilities that the hypotheses in which faith is placed predict the evidence (of the world) while underestimating the probabilities that alternative hypotheses predict the evidence we have." Or, in other words he says:

Bayes's Theorem and the Outsider Test for Faith

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Dr. James A. Lindsay clarifies the OTF using Bayes's Theorem. This is his first post on it. His second post offers a a bit more clarity.

Dr. James A. Lindsay's Bayesian Analysis of the Outsider Test for Faith

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I find his analysis very helpful. He summarizes his post in the following words:

Quote of the Day- by John W. Loftus

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The bottom line is that the odds of a resurrection from my experience are at 0%. No Bayesian analysis can multiply 0 with any other number and get any more than 0. That's what the probabilities are. So I am skeptical of the extraordinary claim that Jesus resurrected since I cannot dismiss my present experience. I must judge the past from my present. I cannot do otherwise! Coupled with the fact that when I read the NT it provides its own demise there is no reason to believe such a claim EVEN IF IT IS TRUE!

Bayesian Background Priors

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[Written by John W. Loftus] A lot is made by Christian philosophers about their background "priors" when assessing the truth of Christian theism. Their claim is that with their particular "priors" they are warranted in concluding from those "priors" the evidence leads them to their faith. My claim is that they have the cart before the horse, big time, bad time.

Special Pleading For God

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[Written by Lee] Compromising Ones Values And Principles To Support Christianity

When I was a Facilitator for Personal Responsibility Seminars we had an exercise where we arranged our values in an hierarchy. We would put two terms together, such as health and cigarettes, and say, for example, "If I could only have one, I would pick health", or "I like or prefer this over that". Then we would look at examples of behavior of the person and see if it matched the values. I think this and a few other thinking skills should be taught in school.

Some Books Where The Process Of Assessing Values Turns Up In Different Contexts
Over the past few months I've stumbled onto some books that have reminded me of some of the exercises we performed in those seminars. Three in particular are
"The Thinkers Toolkit" by Morgan D. Jones
"How To Measure Anything" by Douglas W. Hubbard
"How To Solve It" by George Polya
(if you read the other two you don't need this one. However as far as I can see, it was the first to detail a specific model for problem solving in mathematics which has since been adapted to other contexts such as the first two books).

Start By Defining Terms, Defining The Problem
Of course, in order to do the exercise you have to define those terms. Defining terms such as Good, Bad, Love, Health, Wealth, Success, Peace, Happiness are hard to do because they are subjective, however, common denominators can be found within a range of answers from a range of people and a set of minimum criteria can be derived. But this exercise is not only good for identifying where ones values do not correlate to ones behavior, it is also good for decision making. Its called "Weighted Ranking" and while it is true that this method has its limitations, when the right context arises, it is a powerful tool.

It can be used in evaluating how you really feel about something or someone which is useful in a real world context such as assessing the performance of employees or screening resumes for interviews.

Setting Up The Context Of The Exercise
Here's a silly example off the top of my head of how to do the exercise.
Ted has Diabetes and is overweight. He is out to lunch with friends and they are ordering the type of meals that Ted should not eat. He really wants to share the four cheese pizza with his friends but instead he thinks about what he wants out of life, what his hierarchy of values are and he orders the salad instead. Of course, one of his friends tries to pressure him to conform and eat the pizza too, but he politely declines. Another friend doesn't have as much money as they thought and Ted offers to pay the difference. When they leave the restaurant its raining and Ted offers his coat to a female friend wearing a sleeveless blouse.


How does this relate to Christianity? Thomas Bayes.
It has to do with defining terms, organizing an hierarchy of values and evaluating behavior. Thomas Bayes (1702-1761), a British mathematician, statistician and religious leader, identified and defined an algorithm for the process of belief that seems to be innate in humans. It goes something like the following.
"The probability or likelihood of A given B, C, D, E, F is...."
It doesn't have to be plugged into a mathematical formula, in fact that is not how it is used most of the time. We use it instinctively when deciding what we think about things every day all day. So lets apply it to how we should feel about Ted.

So, how should we feel about Ted? Should Ted be characterized as a "Good Person"?

My definition of a "good person" is .......(write them down).
Is Teds behavior consistent with what I think a good person is?

The likelihood of Ted being a "good person" given
* He chose the salad
* He politely declined when pressured
* He payed the difference in the check
* He gives his coat to his friend.

is high.

New Information About Ted!
The next time we see Ted, he calls Joe at six am on Friday and asks him to swing by on the way to work and pick him up. Ted said he is running late and asks Joe to park the car and come up to the apartment. When Joe gets there he finds that the fender and wheel of Teds car is damaged such that it can't be driven. When he gets up to the apartment Joe finds that the apartment smells like bourbon, the Dog is so thin his bones are showing, the apartment smells like dog urine, there are old dirty dishes in the sink, and Ted is just getting into the shower.


The likelihood of Ted being a "good person" given the new information
* He chose the salad
* He politely declined when pressured
* He payed the difference in the check
* He gives his coat to his friend.
* Teds car is damaged such that it can't be driven.
* The apartment smells like bourbon,
* The Dog is so thin his bones are showing,
* The apartment smells like dog urine,
* There are old dirty dishes in the sink, and
* Ted is just getting in the shower.

is not as high as it was.

Ted probably has personal problems and needs some help, but this forces a re-evaluation of Ted and tightening up of a definition of what a "Good Person" is.

I think where God is concerned, in Christians, this process is interrupted.
They will say that God is Good and Loving EVEN given examples of behavior that would reduce their esteem of a loved one.

One example of this is that fact that supposedly God created Adam and Eve, which means he decided how we would turn out, then when Adam and Eve disobeyed, He kicked them out of their home and put them in the wilderness.

Now if my brother kicked his teenage son and daughter out of the house for disobedience, that would reduce my confidence in his judgment and I would try to convince him that he made a mistake. I think most compassionate people would. But when it comes to God, this principle doesn't apply.

The honest compassionate person when reading through the Bible should see this and other behaviors by God as DISCONFIRMING EVIDENCE that God uses good judgment. If a soldier returns from war and we are told that he cut the baby out of the womb of a mother at the order of his commanding officer, both the officer and the soldier would likely go to court martial justifiably. Yet, God is forgiven of this atrocity.

So lets try it out. Lets do a value system exercise and see how our values correlate to our behavior.

Lets define what we think a good person is and come up with a list. We can define a range of characteristics for what a good person is. In the case that the person contradicts the characteristics by their behavior, their "goodness rating" will decrease. Now think of examples of Gods behavior in the Bible and list them.

Please come up with your own lists, and I invite you to post them in the comments for future reference.

Now try the following.
1. Is God a Person? Well, at least the song says he is: "God in three persons, blessed trinity!"
2. My idea of a Good person is....
3. Is Gods behavior consistent with what I think a good person is?
4. The likelihood that God is a good person given
* instance 1.
* instance 2.
* instance 3.
is [fill in the blank].

Based on my experience here over the past two years and seeing Christians put into this corner, I think this exercise will elicit cognitive dissonance and they will either refuse to do it, or begin special pleading about why it doesn't apply to God.

I'll expect them to say that we cannot judge God by human standards.
I have seen them say that God is good regardless. That he has a reason for his actions we just don't have access to what it is. We don't know what his reasons are. We are agnostic for his reasons but the Bible tells us he's good.

So to them I'll say, "Lets try a little exercise!"

If we are made in the image of God, what does that mean?
It should mean that we should have some things in common with God!
Come up with a list or characteristics that Humans have in common with God.

The likelihood that we are made in Gods image given....
* We can't understand his behavior
* A lot of Gods action don't fall into our definition of behaviors of a good person
* [fill in the blank]
* [fill in the blank]

is [fill in the blank]

The Evidence for the Resurrection

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In an earlier post, I argued that the resurrection of Jesus is initially implausible compared to the possibility the account is an example of legendary development. If Christianity is to be considered even remotely reasonable, then there have to be aspects of the resurrection accounts that are very implausible presuming the legendary development hypothesis.

If I am going to debunk Christianity, it is important to me that I am not merely defeating a straw man version of Christianity. I want to be open to all the relevant evidences for and against Christianity. I also want to use the best analytical tools to evaluate the evidences (hence my prior use of Bayes' Theorem). In this post, I would like to compile the aspects of the resurrection accounts that supposedly make the legendary development hypothesis implausible.

In other posts, I am going to list some of the aspects of the New Testament that seem less likely if the resurrection is true. A fair assessment should not arbitrarily discard any evidence. Subsequently, I will begin the assessment of each of the evidences listed. The goal of this is to see where the evidence points. If Christians are correct the likelihood of the resurrection is very nearly one, if we non-Christians are correct, the likelihood of the resurrection is nearly zero. I want to make the evidence I am considering and my reasoning as open as possible. If there are good reasons to think I am wrong, I want to know them. My goal here is to follow the evidence.

The historical evidence for the resurrection is mostly from Dr. William Lane Craig in the books, "Reasonable Faith" and "Jesus Under Fire". Some of the evidence Craig presents can be found in his debate with Dr. Bart Ehrman here. In that debate, Dr. Craig presents experts' conclusions as evidence. There are some pitfalls to using experts conclusions as evidence. It is quite likely that experts are influenced by things that should not affect ones reasoning, such as their background and/or funding. It is not that experts can't overcome biases, but I want to examine the evidence that should influence the experts. The evidences that really need explanation are aspects of existing documents. The existing documents are copies (of copies) of earlier reports. I am going to am not going to do justice to any piece of evidence here. But if I am ignoring any piece of significant evidence, please let me know.

Aspects of resurrection accounts considered unlikely on the legendary development hypothesis:
  1. The lack of time between the reported event and the reports
  2. The report of James' conversion recorded in Galatians
  3. The report of preaching in Jerusalem which would be unlikely if there was an occupied tomb
  4. Paul's account in 1 Cor 15:3 is unlikely on the legendary hypothesis
  5. The "first day of the week" motif in Mark instead of "on the third day"
  6. The reported discovery of the tomb by women
  7. The report of an early Jewish polemic in Matthew
  8. The lack of a record of tomb veneration
  9. Paul's testimony of the appearance to 500
  10. The narrative of the empty tomb is relatively free of theological and apologetic claims.
  11. The account of the burial seems less likely for a legend
Of course this blog's purpose is to give evidence that is unlikely on the resurrection hypothesis. In addition to the evidences for Christianity, I will also consider evidences that indicate the stories are legendary including: The parallels between of the gospel of Mark and other legends. How Jesus knowledge, strength and control seemed to grow in later accounts. I will also look at the apparent evolution of the story of the resurrection.

If I am missing major aspects of the historical accounts that support the fact of resurrection over legendary development, please let me know.

Comments on Craig's First Rebuttal

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Written by John W. Loftus.


Here I'm going to offer some brief comments on Craig's main argument against Ehrman, found in Craig's first rebuttal linked here.

Against Ehrman he uses the mathematical formula of Bayes's theorem. But what's left out of any equation of this type (as well as Swinburne’s conclusion where he thinks it’s 97% probable Jesus arose from the dead) is that the opponent can object to the values set by the one using the argument.

Here’s Craig (in blue throughout):
And now we’re ready to see precisely where Dr. Ehrman’s error lies. So in the grand tradition of Hume’s Abject Failure, I give you: Ehrman’s Egregious Error.

This is cute and is merely a rhetoric device to label what it is your opponent purportedly does. The mere labeling of this supposed error has no substance to it.

Craig:
He says, “Because historians can only establish what probably happened, and a miracle of this nature is highly improbable, the historian cannot say it probably occurred.”

This appears to be a historian’s version of what is known in scientific circles as methodological naturalism, which assumes that for everything we experience there is a natural cause. We who live in the modern world operate on this assumption ourselves everyday. This assumption is the foundation of modernity. It is what defines us as modern people. In previous centuries we either praised God for the good things that happened to us, or we wondered why he was angry when bad things happened in our lives. But by scientifically investigating into the forces of nature we can better run our own lives, and we know how to make life easier for ourselves, with fewer diseases.

In scientific fields methodological naturalism is a way to gain the truth about nature, and it has astounding results. Some scientists go so far as to claim that since it works, then nature must be ultimate, but that doesn’t follow, for the later conclusion is beyond the scope of science; it is a metaphysical claim. [For discussions about this see “Methodological Naturalism?” by Alvin Plantinga, which can be found at: www.arn.org, “Justifying Methodological Naturalism” by Michael Martin, and “Methodological Naturalism and the Supernatural,” by Mark I Vuletic, to be found at www.infidels.org/library].

Still, if such an assumption has had so many successes in science, then why not apply that method to history as well? And modern historians have done just that. When looking into the past they assume a natural explanation for every historical event. They are taught to be critical of the past, as we’ve just mentioned. As historians they must. That is the standard for what they do as historians, to be skeptical of the past record, especially claims of the miraculous.

According to I. Howard Marshall in I Believe in the Historical Jesus (Eerdmans, 1977) “many historians—the great majority in fact—would say that miracles fall outside their orbit as historians. For to accept the miraculous as a possibility in history is to admit an irrational element which cannot be included under the ordinary laws of history. The result is that the historian believes himself justified in writing a ‘history’ of Jesus in which the miraculous and supernatural do not appear in historical statements. The ‘historical’ Jesus is an ordinary man. To some historians he is that and no more. To others, however, the possibility is open that he was more than an ordinary man—but this possibility lies beyond the reach of historical study as such.” (p. 59).

Craig:
In other words, in calculating the probability of Jesus’ resurrection, the only factor he considers is the intrinsic probability of the resurrection alone [Pr(R/B)]. He just ignores all of the other factors. And that’s just mathematically fallacious. The probability of the resurrection could still be very high even though the Pr(R/B) alone is terribly low. Specifically, Dr. Ehrman just ignores the crucial factors of the probability of the naturalistic alternatives to the resurrection.

Notice the words highlighted? This too is rhetoric. Ehrman does not judge his case against the resurrection in a vacuum. No one does. There are other factors that play into anyone’s assessment of the resurrection. And there is no mathematical fallacy here either. Ehrman just assigns different values to background factors than Craig.

But what value should we place on the intrinsic probability of the resurrection, that is, background factors? That’s the question. Sometimes our background factors against believing in miracles control what we believe so strongly that it would require evidence so complete and overwhelming that one is hard pressed to see that any event, especially in the past, can overcome them. It's not terribly unlike how much evidence it would take to overcome your belief that the Holocaust occurred despite the naysayers, except that with the resurrection we're dealing with a purportedly supernaturally caused event. Likewise, how much evidence would it take to overcome your belief that aliens have not abducted people? What background factors are important here are even hard to specify.

Listen to Gotthold Lessing here: “Miracles, which I see with my own eyes, and which I have opportunity to verify for myself, are one thing; miracles, of which I know only from history that others say they have seen them and verified them, are another.” “But…I live in the 18th century, in which miracles no longer happen. The problem is that reports of miracles are not miracles….[they] have to work through a medium which takes away all their force.” “Or is it invariably the case, that what I read in reputable historians is just as certain for me as what I myself experience?”

Lessing, just like G.W. Leibniz before him, distinguished between the contingent truths of history and the necessary truths of reason and wrote: Since “no historical truth can be demonstrated, then nothing can be demonstrated by means of historical truths.” That is, “the accidental truths of history can never become the proof of necessary truths of reason.”

He continued: “We all believe that an Alexander lived who in a short time conquered almost all Asia. But who, on the basis of this belief, would risk anything of great permanent worth, the loss of which would be irreparable? Who, in consequence of this belief, would forswear forever all knowledge that conflicted with this belief? Certainly not I. But it might still be possible that the story was founded on a mere poem of Choerilus just as the ten year siege of Troy depends on no better authority than Homer’s poetry.”

Someone might object that miracles like the resurrection of Jesus from the dead, are “more than historically certain,” because these things are told to us by “inspired historians who cannot make a mistake.” But Lessing counters that whether or not we have inspired historians is itself a historical claim, and only as certain as history allows. This, then, “is the ugly broad ditch which I cannot get across, however often and however earnestly I have tried to make the leap.” “Since the truth of these miracles has completely ceased to be demonstrable by miracles still happening now, since they are no more than reports of miracles, I deny that they should bind me in the least to a faith in the other teachings of Christ.” (“On the Proof of the Spirit and of Power,” [Lessing’s Theological Writings, (Stanford University Press, 1956, pp. 51-55)].

Back to Craig;
In order to explain that the resurrection is improbable, he needs not only to tear down all the evidence for the resurrection, but he needs to erect a positive case of his own in favor of some naturalistic alternatives.

Okay, so we first have the intrinsic probability of the resurrection, and then we have the evidence. The intrinsic probability for Ehrman is extremely low. When it comes to the evidence, Craig suggests he needs to criticize arguments for the resurrection and at the same time present an alternative theory to explain the present evidence. But if the intrinsic probability of a miracle is close to zero, then I see no reason why Ehrman should have to present an alternative theory of what happened at all. Any theory he might present, even if implausible as he said, would have a greater degree of probability than a resurrection from the dead, given Ehrman's background knowledge,

Craig:
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.

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.

In Ehrman’s defence, he says that a historian cannot say that the resurrection is probable, not that a theologian must do so. But if a theologian concludes Jesus arose, it isn’t based upon the historical evidence. Therefore, Craig’s background knowledge controls what he believes too, and the reason Craig concludes the resurrection occurred is not because of the historical evidence, but because he’s a believing theologian who adopted his faith when he was only 16 years old. [On this click on "John's Posts" in the sidebar and read what I wrote about The Outsider Test].

Besides, Ehrman doesn't have to show that the existence of just any God is improbable. All Ehrman has to do is to show that the existence of the Christian God is improbable. And this would be a case that is easier to make, because in order to make it against Craig all Ehrman would have to do is what we do here at DC on a daily basis with what the Bible says about this God in the Bible. And if the Bible debunks itself, and the Bible tells us about the resurrection of Jesus, then we have an additional reason not to trust what the Bible says about the resurrection.

Craig;
But it gets even worse. There’s another version of Dr. Ehrman’s objection which is even more obviously fallacious than Ehrman’s Egregious Error. I call it “Bart’s Blunder.”

Rhetoric. He’s good at it.

Craig:
Here it is: “Since historians can establish only what probably happened in the past, they cannot show that miracles happened, since this would involve a contradiction—that the most improbable event is the most probable.”

In truth, there’s no contradiction here at all because we’re talking about two different probabilities: the probability of the resurrection on the background knowledge and the evidence [Pr(R/B&E)] versus the probability of the resurrection on the background knowledge alone [Pr(R/B)]. It’s not at all surprising that the first may be very high and the second might be very low. There’s no contradiction at all. In sum, Dr. Ehrman’s fundamental argument against the resurrection hypothesis is demonstrably fallacious.


Ehrman is speaking as a historian from the perspective of methodological naturalism. Ehrman is merely saying that as a historian he cannot step outside what is improbable from the historian’s perspective. In one sense, both Craig and Ehrman agree. They both admit that the intrinsic probability of the resurrection is very low. Because of his studies of the Biblical documents and ancient texts Ehrman considers this intrinsic probability to be extremely low to the point of zero. Ehrman claims that historical evidence cannot lead a historian to believe, and yet even Craig admits that it’s not just evidence, but also background factors which help someone decide that it’s probably true that Jesus arose from the grave. However, these additional background factors, such as the belief in God, are outside the historical evidence too, and hence both of them admit that historical evidence will not in and of itself lead someone to conclude that Jesus arose from the dead.

Probability of Cognitive Dissonance = 1/0

5 comments
When I started a student freethought group at UF, I asked our faculty advisor, Prof. of Philosophy Gene Witmer, whose books I should get if I really wanted to read the strongest arguments that theism had to offer. His suggestion?

Richard Swinburne, Oxford philosophy professor, prolific author of serious works of theistic apologetics (e.g., The Existence of God, Is There a God?, Providence and the Problem of Evil)...who has apparently lost his marbles.

He claims in The Resurrection of God Incarnate to have mathematically calculated the likelihood of Jesus' resurrection, using Bayesian probability, at 97%. His logic [lack thereof]?

  1. The probably of God's existence is one in two. That is, God either exists or doesn't.
  2. The probability that God became incarnate, that is embodied in human form, is also one in two.
  3. The evidence for God's existence is an argument for the resurrection.
  4. The chance of Christ's resurrection not being reported by the gospels has a probability of one in 10.
  5. Considering all these factors together, there is a one in 1,000 chance that the resurrection is not true.

oy vey!

Mark Chu-Carroll has an analysis, if one is even deserved for this kind of madness, which can be summarized thusly:
By a similar argument, I can say that probability of pink winged monkeys flying out of my butt is one in two: that is, either they will fly out of my butt, or they won't. The probability that those monkeys will fly to the home of this Oxford professor and pelt it with their feces is one in two. If pink winged monkeys fly out of my butt, that's an argument for the likelyhood of a fecal attack on his home by flying pink monkeys.

Do I really need to continue this? I don't think so; I'd better go stock up on monkey food in my bathroom.


On another note of sadness, five Mexican children were killed as they prayed at a cross by lightning. Why should we believe there was a God on the other end of those prayers, again? Oh wait, I remember now, everything God does is good, including allowing five children, ages 9-16, to be killed by lightning while offering up prayers and thanksgiving to God. What was I thinking? I'd better go pray for forgiveness...at a plastic cross, of course.