Thursday, July 29, 2010

The Usefulness of Useless Debate

Before I was barred (without any explanation) from posting, I used to spend a lot of time over at Crosswalk Forums, often debating evolution and the age of the earth. At first I thought that there was so much evidence in favor of the accepted scientific view that I would certainly be able to convince the doubters. But I soon realized that there were many ways people evaded the inevitable. Some just buried their heads in the sand and denied the evidence, or said it was unreliable, or faked, or whatever. But others were actually thoughtful, and even well-informed. One in particular was studying biochemistry, and knew much more about genetics than I do. Yet he refused to give up his anti-evolution stance.

Still, it was an interesting intellectual exercise to try to present the evidence in the clearest possible way. And, I thought, even if I wasn't convincing any of my debate opponents, maybe some of those lurkers were getting something of a clearer view of science and its methods.

Just around the time I got banned, someone else posted a poll asking how many forum participants had gone from young-earth creationism (YEC) to evolution/old-earth, and vice versa, as well as who had not changed their stance. Of course, there were many YECs who had remained YEC, as well as those who had been and remained convinced of evolution.

What really surprised me, though, was that there were more who had become convinced of evolution through participation in the forums, than had gone the other way. This in spite of the fact that every argument I posted was immediately inundated with links to, or arguments from, Answers in Genesis and the like.

So I feel strongly that, no matter how useless the debate seems, no matter how unyielding our debate opponents may be, this kind of debate makes an impact.

Thursday, July 22, 2010

The Outsider Test For Faith

John Loftus, of Debunking Christianity, has proposed that believers take what he calls "the outsider test for faith" (OTF).  It is really a very simple idea: that, to be intellectually honest, one should apply the same standards for evaluating one's own beliefs that one applies to others' beliefs. If you want to know the truth, you can't start by assuming that what you already think is the truth. You have to start by being skeptical of what you already think, and looking for ways to test it.

The authors of Triablogue: The Infidel Delusion  don't seem to get it. In a lengthy response to the book, The Christian Delusion, the three authors each respond to John's chapter on the OTF.

Steve Hays begins by asking why a test for religious faith? Why not an Outsider Test for belief in general? As John responds on his blog, he in fact proposes that very thing. The Outsider Test simply asks for a default position of skepticism with regard to any claim. What about an Outsider Test for math? an Outsider Test for physics? An Outsider Test for chemistry? An Outsider Test for biology?

In fact, this is just what we have. If you propose a new theory in physics, you can't just expect other people to believe it. You have to examine it skeptically, look for its weak points, and propose tests. And guess what? It works! Russian physicists agree with American physicists about the Standard Model of Elementary Particles. Chinese chemists agree with French chemists about the rates of chemical reactions. Australian biologists agree with Japanese biologists about the theory of evolution. And so on.

This, of course, is a great contrast to religion, where one's beliefs track closely with where you were raised. Hmmm.

There's a good reason we need something like the Outsider Test to examine beliefs. It's a psychological phenomenon known as confirmation bias. According to Wikipedia, this

is a tendency for people to favor information that confirms their preconceptions or hypotheses, independently of whether they are true. As a result, people gather evidence and recall information from memory selectively, and interpret it in a biased way. The biases appear in particular for emotionally significant issues and for established beliefs.
People are not naturally rational, logical thinkers. We tend to stick to our preconceptions, no matter how much evidence we encounter that opposes them. The genius of the scientific method is that it counters confirmation bias by, first, requiring anyone proposing a new idea to examine that idea as an outsider would, and, second, having other people (who might be less inclined toward confirmation bias) check that idea. As a result, there is widespread agreement among scientists about fundamental theories.

But it's not just scientists. Anyone attempting to establish any claim has to do something like the outsider test: examine the claim skeptically and according to the same standards you use for other claims, and see if it holds up. Historians, for instance, spend a lot of time talking about methodology: deciding what standards should be used to establish claims. In history, you don't have the luxury of doing lots of experiments to see whether your results confirm your theory, so you need to be very careful to establish clear standards.

The Triablogue authors complain that the Outsider Test is biased from start toward atheism or agnosticism. But that's not true at all: it's only a way of asking that the same standards be applied when looking at your own beliefs that you use when looking at others' beliefs. If you accept the healing miracles of Jesus as evidence of his divinity, do you also accept the healings of Asklepios as evidence of his divinity? (There are dozens of first-person accounts of such healings that have been unearthed at the temple of Asklepios at Epiduaros, whereas we only have four, dependent, non-eywitness accounts for Jesus, so the evidence is certainly more secure for Asklepios than for Jesus.)

Here the Triablogue authors bite the bullet and say, yes, they believe in the miracles of other religions (Really? All of them?) and that they are the acts of evil demons. But now we have to take the Outsider Test to another level: if Asklepios healed many people, and the God of the Bible killed people in floods, wars, and plagues, then what makes you so sure that your God is the good guy and the other the bad guy? What standard do you use to judge? And are you applying that standard evenly to all religions?

For these questions, the Triablogue authors have no response.


I finally saw the film Religulous - I have to say I was disappointed. Bill Maher asks someone a question, then  interrupts the answer with "Do you really believe in a talking snake?" and such comments. I think it would have been a more interesting film if he had kept quiet and let the crazies speak for themselves. The best part was when he found a wacky priest outside the Vatican who essentially repudiated all Catholic theology: "Hell? Pfft! That's the old Catholicism!"

The low point was certainly when Maher threw out a bunch of pagan parallels, every single one of which was completely bogus. Probably his research consisted of ten minutes Googling. This sort of thing just plays into the hands of the religious: it's easy to show these claims are false, and thus dismiss Maher as a liar or ignoramus.

Still, I think Maher's approach (like PZ's) is worth the effort. Sometimes a good snort of derision is enough to make someone see the other side. I remember my freshman year of college, when I still thought young-earth creationism was a logically valid option - after all, God could have made those dino fossils and hidden them in the ground, couldn't he? My roommate, not unkindly, said something like, "You don't really believe that, do you?" That was enough to allow me to look at the idea from the outside, so to speak, and realize what extreme special pleading it was.

Wednesday, July 14, 2010

Robert Price, Mythicist

Luke Muelhauser of Common Sense Atheism has posted an interview with Robert Price. Price is well known among atheists as one of the few New Testament scholars who believes that Jesus is entirely fictional. He is not well known among New Testament scholars, however. (In an interview, Bart Ehrman claimed never to have heard of Price.) Price's official home page lists him as a professor at Colemon Theological Seminary, which seems to offer only about 20 courses.

In the interview, Price discusses the sparse evidence for Jesus. He mentions the passage from the Jewish writer Josephus that talks about Jesus and his brother James (Jewish Antiquities, 20.200, quoted here from Wikipedia) he [the high priest Ananus] assembled the sanhedrin of judges, and brought before them the brother of Jesus, who was called Christ, whose name was James, and some others; and when he had formed an accusation against them as breakers of the law, he delivered them to be stoned: but as for those who seemed the most equitable of the citizens, and such as were the most uneasy at the breach of the laws, they disliked what was done....
 Now, I have read several scholars who have addressed the evidence for Jesus, and this passage is generally considered an authentic reference to the Jesus of Christianity. Price, however, makes a startling claim:

"If you look a little farther, it says that James and Jesus were  the sons of a guy named Damneus, and that they were candidates for the high priest - it wasn't Jesus of Nazareth at all!"

So, what's the story here? Have all those other scholars simply missed the fact that this Jesus was the son of Damneus and a candidate for the high priesthood? Well, here's how the rest of the passage runs:

...they also sent to the king, desiring him to send to Ananus that he should act so no more, for that what he had already done was not to be justified; nay, some of them went also to meet Albinus, as he was upon his journey from Alexandria, and informed him that it was not lawful for Ananus to assemble a sanhedrin without his consent. Whereupon Albinus complied with what they said, and wrote in anger to Ananus, and threatened that he would bring him to punishment for what he had done; on which king Agrippa took the high priesthood from him, when he had ruled but three months, and made Jesus, the son of Damneus, high priest.
Note that, contrary to what Price says, there is nothing here about James being a candidate for the high priesthood, or being a son of Damneus.

Notice too that the earlier passage mentions "Jesus, who was called Christ," whereas the second passage identifies "Jesus, the son of Damneus." Price doesn't say why he thinks these two are the same person; it certainly isn't implied by the text. "Jesus" was not such an uncommon name: a little later, Josephus mentions that Jesus, the son of Damneus, was succeeded as high priest by Jesus, the son of Gamaliel. It seems more likely, in fact, that "Jesus, the son of Damneus" is being distinguished from "Jesus, who was called Christ."

Now, Price is giving a web interview, not writing a scholarly paper, and perhaps he has something more complicated in mind. Earlier in the interview, Price discussed the other place where Josephus mentions "Jesus, who was called Christ" (Jewish Antiquities, 18.63-64). Price points out that Josephus himself considered the emperor Vespasian to be the Jewish Christ/Messiah (a bit of flattery from Josephus to his imperial patron), and so was unlikely to use "Christ" to refer to anyone else. Maybe Price thinks that "who was called Christ" was missing from the original text, and inserted later by a Christian author. (This is similar to what many scholars think happened with Jewish Antiquities, 18.63-64. You can read about it in the Wiki article.) But then, what would have originally been in its place? Perhaps "Jesus, the son of Damneus", as it appears later? But, if Josephus had already identified this Jesus as "son of Damneus", why would he need to identify him again? Why wouldn't he just say "Jesus"?

For comparison, look at 20.197:

As soon as the king heard this news, he gave the high priesthood to Joseph, who was called Cabi, the son of Simon, formerly high priest.

Here Josephus identifies Joseph as "the son of Simon." But in the next chapter, Josephus continues

But the king deprived Joseph of the high priesthood....

Here, once having identified which Joseph he was talking about, he just refers to him as "Joseph" without any other identification. So, if "Jesus, the son of Damneus" was what Josephus originally wrote, then we would expect "the son of Damneus" would not be needed in the later position if it were the same Jesus that became high priest.

So I can't make any sense out of Price's claim that the James who was stoned was the brother of  Jesus, the son of Damneus. Perhaps Price has argued this all out in some scholarly article. But it seems to me to be a case of choosing the interpretation that fits your preconceived outcome, rather than the interpretation that makes the most sense.

This may seem to be too small a point to be worth all the verbiage - but it makes me cautious about everything he says in the interview. If he is willing to play fast and loose with the text here, how reliable are his other claims?

Thursday, July 8, 2010

We Have The Fossils - We Win!

If you spend any time arguing with creationists (I used to do a fair amount of this), it's helpful to have some actual data on hand. I'm a math-geeky guy, so I like charts and stuff. One of my favorites is from an old post on Panda's Thumb.

It shows an unbroken increase in brain size (cranial capacity) over the past 3 million years. The magnitude of this increase is just astounding: from 400 ml (about the size of a chimp's) to around 1200 ml - a tripling of brain matter!

The thing is, there's really an astonishing amount of evidence for human evolution: a dozen extinct hominid species comprising hundreds of fossils. Compare that to the number of chimpanzee fossils that have been found: zero! Some religious folk admit that the evidence for evolution is overwhelming, and accept that it was the way all animals and plants came about - except for humans, who were specially created by God. Given the fossil evidence, though, it would be much easier to make the case for special creation of chimps!

Brain size is, of course, not the only important difference between humans and other animals. But there are some profound advantages to focusing on a single characteristic like this. In the usual way of discussing evolution, one classifies the fossils into different species and talks about the average characteristics of each species, "Homo habilis had an average cranial capacity of 500 ml," etc. But then, creationists point to the "jumps" in brain size between species and shout, "Gaps in the fossil record!" The graph, on the contrary, shows that there really are no gaps in the brain size record. Likewise, when discussing one species at a time, creationsists will try to call them "just another ape" or else "just ancient humans." Show them this graph and ask them where they draw the line between apes and humans.

Finally, the graph refutes the creationist claim that the theory of evolution makes no testable predictions. The link between brain size and age in hominid fossils is a clear prediction of Darwin's theory: if humans evolved from smaller-brained primates, then there must have been primates with intermediate brain sizes. At the time Darwin made his proposal, there was no fossil evidence to back it up. (Only one Neanderthal fossil was known at the time, and no other ancient hominids.) The discovery over the last century of all these intermediate fossils provides resounding confirmation of the theory - regardless of whether these species were on the direct line of human ancestry or not.

(NB: the title of this post is stolen from this bumper sticker.)

Sunday, July 4, 2010

The Problem With Mythicism In A Nutshell

James McGrath at Exploring Our Matrix is reviewing The Historical Jesus: Five Views chapter by chapter. I haven't read this book yet, but it looks like one to put on the to-read list.

The first chapter, by Robert Price, presents the "mythicist" view: that Jesus was not a real, historical person, but was from the beginning a fictional character in an invented myth. While this is a popular view among some atheists, it is a view held by hardly any actual New Testament scholars. (I have attempted to summarize the main arguments elsewhere.)

McGrath nicely exposes the difficulties in Price's approach:

And this is where we can return to Price's ignoring of his own stated principles. He states that everything is possible in theory, and so asks what is probable. And yet he never shows that the scenario he envisages for the emergence of Christianity and its narrative texts is anything other than possible, at best, and that provided one is willing to assume a number of controversial points which likewise remain unjustified.

For instance, is it possible that early Christians went through the Jewish Scriptures, choosing a story here, a turn of phrase there, and weaved them together to create a fictional Messiah? Certainly - as are all other scenarios. What is never explained is why someone would have done this, much less done it to produce a crucified Messiah rejected by his contemporaries. If nothing else, Price's mention of Occam's Razor at this juncture seems so ironic as to be comical (p.74). How is an unparalleled process of fabricating a fictional Messiah from texts that would have had to have been painstakingly combined a simpler explanation than that there was a historical figure of Jesus, about whom stories were sometimes created to fill in gaps in his followers' knowledge or to cause him to address issues that he had not?

Price has shown that it is indeed possible to imagine a scenario in which Jesus was invented - that was never in dispute. But his chapter has also demonstrated, I believe, that historians are right to favor the conclusion that Jesus existed, however obscured by legend he may be from our view. Because if we consider the weak and tendentious case Price made for his conclusions, having emphasized that it is not possibility but probability that he needs to demonstrate, then I can only conclude that it is the best case that can be made for mythicism, since there is no one that I know of who is trying to make a case for mythicism that has better and more relevant qualifications than Price does.

I'm not entirely in agreement with that "best case" bit: Earl Doherty, though not having the qualifications that Price has, has developed a more detailed mythicist scenario. But I'm glad to see NT scholars engaging the mythicist position and explaining their reasons for rejecting it. This chapter, and the responses to Price from the other contributors, looks to be an important contribution to public understanding of the issue.

Thursday, July 1, 2010

Why Isn't Tomorrow Ever Yesterday? Part II

Last time, I introduced the question of the arrow of time and Sean Carroll's proposed solution of it. Now I want to ask what it is that this solution solves.

First, a little about the nature of physical models. There are the equations of the theory - say, general relativity, or the Standard Model. The equations (we suppose) apply to a wide variety of different situations. In addition, there are boundary conditions that apply to some specific situation that we are trying to model. For instance, if I want to model the water in a beaker, I need the equations of fluid dynamics, but I also need to specify the conditions at the boundary of the water: where the water meets the beaker. In this case, I would need to specify the shape of the beaker and give some condition for what the water does when it hits the edge.

The equations of the theory will respect some symmetries, like the time reversal symmetry I mentioned last time. But the solutions of the equations will not necessarily respect the same symmetries. Take, for example, the simple case of a freely moving object in an otherwise empty spacetime. The equation of motion is:

Acceleration = O

This equation has rotational symmetry: it doesn't single out any particular direction in space. Now consider a solution to the equation for a specific object, say a rock. The solution is that the rock's velocity remains constant. But if the rock is moving at all, it is moving in some particular direction. The solution singles out a special direction in space: the direction of motion. The solution for a particular situation will not, in general, display the same symmetries as the equations of motion.

From this point of view, there's no need to worry about the fact that the universe starts out with low entropy: the low entropy is simply a boundary condition we need to impose in order to produce a model that reflects the universe we live in. The lack of time reversal symmetry is not mysterious: the equations of physics are time reversal invariant, but the boundary conditions are not.

What, then, does Carroll's "explanation" of time reversal asymmetry actually explain? Carroll cannot avoid the issue of boundary conditions. His slab of de Sitter space acts as the boundary condition for the droplets that are the baby universes. He has just replaced one boundary condition with another. True, his choice of boundary condition restores some kind of overall time symmetry to the solution. But that symmetry is completely unobservable, because the other baby universes are causally disconnected from our universe. If Carroll is right, there is no way we will ever know it!

Now, maybe I'm not being fair to Carroll's model. Maybe there is something in the process of spawning baby universes that gives specific, testable predictions. And maybe some day those predictions will be confirmed. But even if they are, the overall picture can never be tested experimentally. Specifically, the time symmetry aspect - which, after all, is what Carroll claims to be explaining - can never be checked.

To me, this removes the model from the realm of science. The existence of other baby universes is a purely metaphysical question: do you prefer a picture which has an overall time symmetry, or can you live without it? Does it bother you to postulate an infinite number of unobservable universes, or are you OK with that? Certainly esthetic principles have played a role in theoretical physics in the past and have led to deeper understanding. But when your esthetic principle leads to a picture that is completely untestable, I wonder whether it has any scientific value.