What is often forgotten, though, is that the probability of an event requires relating two things: (1) the evidence for that event (which is what we usually think of), but also (2) the prior probability that the event would occur.
For example, suppose I make the claim, "I just flipped an unweighted coin twenty times, and got all heads!"
What is the likelihood that I am telling the truth? Some combination of two factors: (a) the odds of achieving this result, which (on exactly 20 flips) would be 2^20, or about one in a million, and (b) the odds that I am lying or mistaken. (Maybe I wasn't paying close attention, or maybe both the coin and my eyes are old, and the two sides of the coin look the same to me. Or maybe the coin is, after all, weighted, or perhaps I am suffering a drug-addled hallucination from years of playing Russian Roulette in a smoke-filled bar in Saigon.)
If I say, "I flipped a coin three times in a row, and got all heads," you would likely nod your head and go back to your Kindle. If I claim to have done so 300 times in a row, you would have every right to be extremely skeptical. At some point, the improbability of the event will tip the balance against the improbability (I hope most readers will agree) of various perhaps attenuated "liar" or "lunatic" hypothesis. In the technical, arcane language of legal philosophy, you "smell a rat."
Prior probability is often overlooked, or under-emphasized, in popular discussion of the Resurrection of Jesus. Someone like William Lane Craig, Gary Habermas, or Josh McDowell (for the old school) will argue that the historical evidence for the resurrecion is actually very good. Then skeptics will try to undermine that claim.
The Christian will generally win that argument, because as historical evidence goes, the evidence for the Resurrection of Jesus IS remarkably good. The main challenge may be to get the audience to grasp the value of historical evidence, with our bias for forensic or other "scientific" evidence. But given a fair appreciation of historical method, and a competent description of the evidence, this case can easily be made. If all that were being asserted were that St. Peter caught a very big fish that day, the event would be universally admitted as having been proved beyond any reasonable doubt.
But then the skeptic, and maybe even the Christian (even Alvin Plantinga, in some moods), will go home and ask himself, "Yeah, but can you really prove something so contrary to human experience as a resurrection from the dead, from any amount of historical evidence?"
Indeed, read the Book of Acts closely, and it's clear that this objection goes back at least to St. Paul's sermon before the Committee for Skeptical Inquiry that met on Mars Hill in Athens. "God did what? Go on! Get out of here!" But up to that point, they were listening carefully to Paul's more philosophical and moral arguments for theism.
A frequent visitor to this site, the Irish skeptic Brian Barrington, once posted a tongue-in-cheek argument against the Resurrection based on a "prior probability" against it of 100 billion to one.
He didn't explain how he got that figure. But I think what he based it on, was the number of people who have lived on Planet Earth over the past two thousand years. The assumption, following Hume, seems to be that experience of an event should be deemed proportional to the frequency of similiar events. If 100 billion people have died without rising, there should be a presumption against any one person rising from the dead, of 100 billion to one.
I pointed out that in fact, no one has any historical evidence about the post mortem fate of the vast majority of human beings since Jesus. Some other resurrections HAVE been alleged -- even in the pages of the New Testament. So even supposing that resurrections strike people as randomly as lightening or meteorites, still the ratio of people whom we know in a strong historical sense have not have risen from the dead, to those about whom we might have some evidence to the contrary (say Lazarus), is much less than 100 billion to one.
But of course no one claims Jesus' resurrection was just a matter of luck. Christians, and even the occasional Jewish scholar who buys into the story, never suppose Jesus won the resurrection ticket in a random cosmic lottery. On any reasonable account, if God exists and acts in the world, Jesus was far more likely to rise from the dead than, say, Al Capone, or even Joe the Plumber.
"Prior to what?" The prior probability of the resurrection is the probability that Jesus would rise, considered prior to the historical evidence for or against his resurrection. My claim is that there are other facts -- including some which no reasonable person denies -- that vastly increase the probability that Jesus might be resurrected, as opposed to one of the billions of other people who have lived in historical times.
The prior probability of Jesus' being raised would seem to be a function of three issues: (1) Does God exist? (2) How likely would he be, even while keeping the laws of Nature generally in effect, as He obviously does -- including entropy in general and human death in particular -- raise one person dramatically from the dead? (3) How likely would it be that that person be Jesus?
(1) The probability that God exists will approach one for many people, zero for others, with other people falling at all spots in between. But the arguments are complicated, and it would be foolish to begin arguing about the resurrection by first trying to solve so involved an issue, that is never solved to everyone's satisfaction. Theists have arguments for the existence of God that are independent of the resurrection of Jesus. If we begin with belief in God, or the strong probability that God exists, BEFORE discussing the resurrection, we will not be begging the question for ourselves, but might be begging it for non-theist readers. And we will be leaving out one plausible reason for believing in God. So what should we do?
One might deal with the "God question" in one of two ways. First, we might "compromise" by taking the existence of God at 50-50, just to see how the rest of the argument works. Or second, we might make the existence of God a variable in the equation, and use the resurrection of Jesus as an argument to faith in God. Both solutions are ways of bracketting this issue, and perhaps coming back to it later, better-informed.
Let's go with the first option, here. I think 50-50 is a fair number to assign, for the following reason. People are intelligent creatures, but also prone to fooling themselves at times. (Including, of course, myself, and the reader.) We may have both worked over the evidence for faith many times, and come to different conclusions. So who is really fooling himself, or herself? We can work over the evidence for decades, and both walk away thinking the other person is missing the point.
In this case, I think it is valid to tentatively make a sort Ad Populum argument, as a short-cut. Let us appeal to what society at large, our friends and neighbors and humanity in general, believe, as a temporary control over our own opinions.
Most people believe in God. Far fewer extremely well-educated people claim to believe in God. Maybe that's because they're more intelligent, better education, and know more about, say, evolution or the Big Bang. On the other hand, the Bible predicts that "the wise" are liable to becoming proud and self-dependent, and fail to recognize their need for God. The Lord "opposes the proud, but gives grace to the humble." Though of course not all believers LOOK gracious, and some intelligent skeptics seem highly sincere. Furthermore, miracles and other signs of God's reality might be more likely to occur among those who are needy, if the Bible is any guide, not among the comfortable.
So there are competing explanations for atheism (I give several others in The Truth Behind the New Atheism), and in some societies, Christians seem more heavily represented among the highly educated than among lower classes.
So I think a fair shortcut to reworking all the arguments, which we can't do for a premise here, is to compromise between classes and cultures, our own intuitions and arguments and Vox Populi, and call it (for the sake of the argument) a 50-50 shot.
Again, if you don't like this figure, don't worry -- the evidence of the resurrection may cause it to increase.
(2) The likelihood that God, should he exist, would act in this one particular way, by raising someone from the dead, is also hard to be sure about, since we are unable to read the mind of God. (Of course, it does not follow that He cannot tell us His own mind, which Christians claim He has, in the Bible, for instance, and perhaps in other ways.) That God would do such a thing, does not seem wildly unlikely, though, given: (a) God is, by hypothesis, good, and would want us to have hope; (b) God created Nature, and therefore presumably has good reason to allow the regularities that we call "natural law" to be manifest most of the time; (c) Much of the offense skeptics take at miracles seems to be aesthetic; it seems inartistic, crude, etc, for the laws to be set aside too easily; (d) Yet one can see intuitive sense in God offering some dramatic sign (as it is called throughout the Bible), some "eucatastrophe" as J. R. R. Tolkien put it, some "good disaster" by which (to cite his friend C. S. Lewis) the "laws of nature would begin to work backwards," so that Entropy would not have the last word, and the "sting of death" be drawn, may seem like amazing good news, presumptuous to assume, but hardly out of character for a good God. Raising someone from the dead, at a key juncture in history, might well be part of His plan.
It seems presumptuous (aside from His revelation, which is in dispute) to put a number on "what God would do." But by the same token, it would also be presumptuous to assume dogmatically that He would not do such a thing.
This question, too, is difficult to solve decisively in a short discussion. But it does not seem an overwhelmingly unlikely idea a priori. Only a little evidence that this might, in fact, be God's will, would seem enough to make it sufficiently credible.
In the same way, since a late spring storm just brought new snow to the Cascade, and I love to ski, even though I have work to do, and should probably stay home and do it, it is not overwhelmingly improbable that I will drive up to Snoqualmie Pass today and do a bit of skiing. One can see why this might happen. If you think you see me there in a few hours, it will be very possible that you do.
Perhaps one could put the possibility that God would do such a thing, a priori, at one in 10. Given hints in Isaiah that after dying for the sins of the people, the Suffering Servant would "see the light of life," (and given the existence of God already accounted for in ), we might fairly put that number higher, say 1 in 4.
(3) To evaluate how likely a given person might prove to be the one through whom God reveals his power, let's begin with Martin Luther King. Suppose God wanted to dramatically not just want to show that Entropy would not have the last word, and that there was hope for the human race, by raising a prominent person from the dead. Suppose he also (again, following his character as developed in the OT prophetic works) also wanted to reprimand oppressors by his choice of whom to resurrect. King might be a good person to pick. His resurrection would not only give people hope for life after death, but also demonstrate that God was on the side of non-violence and human rights.
On the other hand, King's resurrection might also send mixed messages about how to treat women, for example, or force God to "pick sides" in American politics. And there are other heroic figures who might do just as well -- Gandhi, say, or Socrates. So given that God exists, and He wanted to prove his power and character and the hope of eternal life by raising one man from the dead, one might suppose the chance that he would pick Martin Luther King might be, say, one, in a one thousand -- much higher than someone picked at random, say Otzi the Iceman, one might reasonably suppose.
In this scenario, would anyone be more likely to be raised than Jesus?
Consider the following facts, none of which depend on the historical accounts of Jesus' final days in the NT:
(a) As mentioned above, Isaiah spoke of a Suffering Servant dying, yet then "seeing the Light of Life." Might not this and other passages in the OT be a signal pointing to God's intention not just in general, but specifically related to Jesus? Christians, including so perceptive a man as Blaise Pascal, have traditionally found many messianic expectations in the Old Testament that seemed to come true in Jesus, more than in the life of any other man or woman. All in all, the diffuse and complex web of Messianic expectations, that do seem to focus on Jesus (Pascal explains some of the reasons why), do seem to make it far more likely that he would be the one whom God raises.
(b) The ancient Hindus wrote of God (Prajapati) sacrificing himself for the world. There are parallels in China and in other cultures (see my previous post), and mythological "dying and rising gods."
Again, some of these show remarkable parallels to the person and story of Jesus. If God were to intend his act as a sign not just to Israel, but to the whole world -- and the entire Old Testament underlines the universal character of God's redemptive plans -- then does not the fulfillment of such types in the life of Jesus greatly increase the chance that He would be the One prepared for all mankind -- and that God might (going back to ) give humanity a sign of hope and redemption in one such fell, miraculous deed?
(c) Lin Yutang, the great Chinese philosopher and man of letters, who compiled an anthology of Chinese and Indian literature, said that "no man has taught as Jesus taught." Many others on a similar intellectual plane concur. Is it not more likely that God would choose arguably the world's greatest moral teacher to make His point?
(d) Jesus was, as I show in The Truth Behind the New Atheism and elsewhere, at the center of many of the greatest reforms in history -- inspiring them, setting an example, more so than anyone. Is it not likely God would choose to raise such a person, to set an example for the human raise, and thus endorse his example? (Leading to such reforms as have in fact occurred?)
(e) Jesus was murdered by tyrants, backed by the Roman Empire, in a particularly savage way. If God is (as Lao Zi said of the Dao) on the side of the weak against powerful oppressors, would not raising him from the dead be a particularly good way of showing that?
One could go into a great detail on each of these points, and I have done some of that elsewhere. But let me now begin to get to the point.
I haven't introduced any specificially Christian theology into this argument. Even so, these factors seem to show that, if there is a God, and if He intends our redemption through some such act, then the resurrection of Jesus is most to be looked for. If God exists, and if He wanted to do something dramatic in human history, that would change the world, give us hope, and show that he stands on the side of the righteous and oppressed, Jesus would seem to be the best possible tool through whom to express that. (Whether or not he was, himself, divine.)
In fact, one might say that not only is Jesus the most likely candidate, he is the only really likely candidate. Buddha and Lao Zi are almost lost in the historical mists. Mohammed was a bloody conqueror. Confucius was a cautious gentleman, whose teachings were useful, but which could not have dramatically changed the world for the better, as the Gospel has. Gandhi and King were great men, but their movements were inextricably political, and their personal lives not always as inspiring as their ideals.
So it does not seem wildly unreasonable to suppose, prior to looking at any historical facts at all, that there is at least a one in ten chance that God (assuming Him to exist, and to be of such a mind) would have chosen to raise Jesus, of all people from the dead.
One might even say rhetorically (in reading the Gospels, or in frustration at the cruelty and injustice of life) that it would be a miracle if God did NOT raise Jesus from the dead.
Given all that, the prior probability of the Resurrection of Jesus might be as great as, say, 1 in 80 (2 X 4 X 10), and is certainly far greater than one in 100 billion.
If there are independent reasons for believing (1) and (2) that make those odds better than even, as I think there are, then the prior probability of the resurrection, before we even begin to examine the actual historical evidence, might rise to 1 in 10, or so.
If, then, the purely historical evidence for the Resurrection is strong -- and I think Christian historians have shown that it is tremendously strong (see for instance this wonderful piece by Tim & Lydia McGrew)-- then the combined evidence that in fact Jesus DID rise from the dead, as reported, may become quite strong, even prohibitively strong. In that case, one can "flip" the resurrection equation around, and solve it for "Does God exist?" It then becomes reasonable to argue from the Resurrection to the existence of God.
Of course, this conclusion depends on the plausibility of each step of this argument.
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