Sunday, February 27, 2011

JI: What was Mary & Joseph's Hometown?

Ehrman spends pages 29–35 of JI covering the Jesus' contradiction-riddled birth narratives (Matthew 1:18-2:23 and Luke 1:5-2:40). One that I think is particularly obvious when the texts are carefully compared is the location of Mary and Joseph's hometown. Here's what Ehrman says about it:
"According to Matthew, what is Joseph and Mary's hometown? Your natural reaction is to say 'Nazareth.' But only Luke says this. Matthew sats nothing of the sort. He first mentions Joseph and Mary not in connection with Nazareth but in connection with Bethlehem. [2:1-2] The wise men, who are following a star (presumably it took some time), come to worship Jesus in his house in Bethlehem. [2:11] Joseph and Mary evidently live there. There is nothing about an inn and a manger in Matthew. Moreover, when Herod slaughters the children, he instructs his soldiers to kill every male two years and under. [2:16] This must indicate that Jesus had been born some time before the wise men show up. Otherwise the instruction does not make much sense: surely even Roman soldiers could recognize that a toddler walking around the playground was not an infant born some time last week. So Joseph and Mary are still living in Bethlehem months or even a year after the birth of Jesus. So how can Luke be right when he says that they are from Nazareth and returned there just a month or so after Jesus' birth? Moreover, according to Matthew, after the family flees to Egypt and then returns upon the death of Herod, they initially plan to return to Judea, where Bethlehem is located. [2:22] They cannot do so, however, because now Archelaus is the ruler, so they relocate to Nazareth. In Matthew's account they are not originally from Nazareth but from Bethlehem."
Ehrman summarizes everything well, but I want to expand just a bit on that last part. Here's Matthew 2:22-23:
"But when [Joseph] heard that Archelaus was reigning over Judea instead of his father Herod, he was afraid to go there. And being warned by God in a dream, he turned aside into the region of Galilee. And he came and dwelt in a city called Nazareth, that it might be fulfilled which was spoken by the prophets, 'He shall be called a Nazarene.'"
I'm going to break down the language in this passage to make it entirely clear why it shows that, according to Matthew, Mary and Joseph did not originally live in Nazareth.
  1. "he was afraid to go there" – Joseph had planned to return to Bethlehem in Judea.
  2. "he turned aside" – Joseph did not originally intend to go into Galilee.
  3. "he came and dwelt in" – This perfectly describes moving to a new town. Had Matthew wanted to describe arriving home, he would have said "came back to" or "returned to."
  4. "a city called Nazareth" – Matthew introduces Nazareth as a completely novel location, as though nothing relevant has previously occurred there.
  5. "that it might be fulfilled" – The purpose is not to return home, but to fulfill a prophecy.
It's worth noting that there is no prophecy that "He shall be called a Nazarene" anywhere in the Old Testament. Apologists have tried to make sense of this in various ways, but the bottom line is that Matthew basically made it up. There's also a Bethlehem prophecy quoted in Matthew 2:6, a very rough paraphrase of Micah 5:2 (compare them here). Ehrman tells us why this is significant:
"[T]here is a prophecy in the Old Testament book of Micah that a savior would come from Bethlehem. What were these gospel writers to do with the fact that it was widely known that Jesus came from Nazareth? ... To get Jesus born in Bethlehem but raised in Nazareth, Matthew and Luke independently came up with solutions that no doubt struck each of them as plausible."
So, to review: Matthew heavily implies that Mary and Joseph were from Bethlehem, he gives every indication that they were not from Nazareth, and he has a prophetic motive for constructing the narrative the way he did. If we provisionally assume Luke's narrative is correct that Nazareth was their hometown, then Matthew's account on this point is thoroughly deceptive at best and irreconcilably conflicting at worst.

Friday, February 25, 2011

Developments at UCSD

I have two quick things to talk about in terms of happenings at UCSD. First, on March 7, Dan Barker is debating Dinesh D'Souza on the question, "Is Religion the Problem?". Unfortunately, it's happening at exactly the same time as a club meeting of mine, and I probably won't be able to make it, but there's a fairly good chance it'll be filmed and uploaded to YouTube. I'll watch it and give my commentary if and when that happens. (My sister's Bible teacher also informed her of a creation-evolution debate supposedly happening at UCSD in April. I've searched online and can't find anything on it, so he may have been mistaken.)

Also! Rational Thought at UCSD put out an "Ask an Atheist" table on Library Walk today (ironically, with music from a worship concert blaring in the background). The booth was decorated with flyers asking good, provocative questions that I'm sure many theists wonder about (e.g. "What will you be thinking about on your deathbed?" and "Why be moral when no one is looking?"). I signed up for their e-mail list to get some information about upcoming events and such. I also asked one guy if he had any advice about "coming out" to my friends and family about my unbelief. He said he didn't have any experience with that, but he could probably put me in contact with someone who did. Overall, they seemed like a very intelligent, articulate and friendly bunch, and I wouldn't at all mind going to one of their meetings sometime.

Update: I got an invite to a "Coffee and Conversation" meeting on Monday at six. I'm generally very introverted when it comes to discussion groups, but I think I'll try it out. If anything comes of it, I'll write about it here.

Thursday, February 24, 2011

A False Echo of Discontinuity

Much to my dismay, my sister gets a monthly magazine (at the request of her Bible teacher) from the Institute for Creation Research called Acts & Facts. I've peeked into it a few times, and it seems pretty shallow in general, but there are articles here and there that actually make tangible claims about evolution. Last month's issue included a short article called "Molecular Equidistance: The Echo of Discontinuity?", written by Nathaniel T. Jeanson.

Jeanson examined cytochrome b, a gene found in almost all organisms. Here's the data that the article focuses on.

The more closely related two species are, the more similar their genes are, which constitutes powerful molecular evidence for evolution. A human's cytochrome b gene is 79% similar to a panda's, 75% similar to a tortoise's, and so on. However, as Jeanson points out, yeast's cytochrome b is equally similar (50%) to all the other animals on the list. He claims:
"Evolutionists hail the ordered, hierarchical pattern of human-to-other-species comparisons (depicted in the leftmost column of the table) as a fulfillment of the predictions of [evolution]. However, as Michael Denton observed ... the rows of data depict something entirely different. As demonstrated by the comparisons of yeast to every other creature in the table (depicted in the bottommost row), the yeast cytochrome b cannot be arranged in any sort of hierarchy with the other creatures; yeast is equidistant from all other creatures. Hence, it appears that yeast cytochrome b is isolated, separate, and completely distinct from all other species in the table—it is as close to beetles as it is to humans! In a sense, yeast appears discontinuous from the other creatures in the table. This is consistent with the predictions of Genesis 1."
Initially I was surprised by this assertion, and it seemed reasonable on the surface (although how exactly this was "predicted" by Genesis is unclear). But then I noticed Jeanson's reference to Michael Denton's book Evolution: A Theory in Crisis, which had apparently done the same thing with cytochrome c, and it occurred to me that this claim may have been dealt with before. I was right, and as soon as I saw the criticism of Denton's work, everything clicked.

I'll try to explain with an illustration. Below is a hugely simplified graph I created to show genetic divergence. The numbers in blue represent pieces of genetic information that are modified by mutations over time.

This might be a bit confusing, but stare at the numbers for a while and the pattern should become clear. The four different digit positions are there only to distinguish between mutations before and after each speciation event. In this simplified model, each type of animal undergoes one mutation at each time point, represented by the number at one of the positions increasing by one; higher numbers mean greater divergence. We'll call the leftmost digit position "first position," followed by second, third and fourth.

Now let's do a bit of arithmetic. How many "genetic divergence units" away are reptiles from mammals at Point #5? They differ by 2 in the third position and 2 in the fourth position, which makes 4 units altogether. Amphibians differ from mammals by 3 in the second position, 1 in the third position, and 2 in the fourth position, for a total of 6 units. Finally, fish differ from mammals by 4, 1, 1 and 2, for a total of 8 units. These relationships mirror the columns in Jeanson's table.

Now, how many units away are fish from amphibians at Point #5? They differ by 4 in the first position and 4 in the second position, or 8 units total. If we do the same with fish/reptiles and (again) fish/mammals, we find that these pairs are also 8 digits apart. This mirrors the rows of Jeanson's table.

So why do we get these results? The most important thing to recognize is that amphibians have spent just as much time undergoing mutations and diverging from fish as reptiles and mammals have. However, the same is not true if we look at it in terms of mammals: in this graph, reptiles and mammals have the same evolutionary trajectory for a long time (until after Point #3), amphibians and mammals for a medium amount of time, and fish and mammals for short time. Naturally, the longer two animals share an evolutionary history, the more similar their genetic information will be. The results we get here and the results in Jeanson's article are exactly what evolution predicts. (If this explanation was unclear, the one in the second half of this review may be helpful.)

Here's the bottom line: Jeanson is utterly and undeniably wrong. And he's not just wrong: he borrowed a faulty argument from a 25-year-old book to use as the central thesis of his article. Then the fine folks at Acts & Facts took that article and published it. Apparently neither party thought it might be a good idea to see if there had been any criticism of that work over a period of two and a half decades.

Jeanson and Acts & Facts are either totally ignorant of the fact that Denton's argument has been refuted, not smart enough to understand that refutation, or too dishonest to care about it. And now thousands of creationist readers will add another piece of illusory evidence to their arsenal of falsehoods. Whenever I dig deeper into a creationist claim, this is what I get. It's enough to make me wonder whether I should even bother.

Tuesday, February 22, 2011

Is the Singularity Near?

Time magazine has an article about the Singularity – a point in the relatively near future at which the rate of technological advancements will supposedly skyrocket, ushering a new era of... something. It's not clear, but Singularitarians advise humanity to brace itself. Many people see the movement as a kind of secular, science-based religion (it's been called "the rapture for nerds"), so I thought it would be appropriate to discuss it here.

The Singularity's most prominent advocate is futurist Ray Kurzweil, who claims that humanity's technological advances can be plotted on a logarithmic curve, culminating in a Singularity around 2045. PZ Myers of Pharyngula has made several posts criticizing Kurzweil's claims, and after reading them I must say I agree with him. For example, Kurzweil plots mammals, primates, and humans as "innovations" on his exponential growth curve. PZ says:
"If you're going to use basic biology as milestones in the countdown to singularity, we can find similar taxonomic divisions in the cow lineage, so they were tracking along with us primates all through the first few billion years of this chart. Were they on course to the Singularity? Are they still?"
Kurzweil says we'll reverse engineer the brain in 20 years based on the relative simplicity of the genome. PZ says:
"Kurzweil knows nothing about how the brain works. Its design is not encoded in the genome: what's in the genome is a collection of molecular tools wrapped up in bits of conditional logic, the regulatory part of the genome, that makes cells responsive to interactions with a complex environment. The brain unfolds during development, by means of essential cell:cell interactions, of which we understand only a tiny fraction."
In short, Kurzweil is a smart guy who's competent in certain areas of computer science. But his ideas about exponential growth, while superficially interesting, should be taken with a shake of salt or three.

The idea of a Singularity isn't uniformly ridiculous, however, and there are other views of the phenomenon that are different from Kurzweil's. Ultimately, what it comes down to is this: Can we create a being (be it an augmented human or an AI) that's smart enough to create a smarter being (or make itself smarter), which can then do the same thing itself, and so on? If so, we could plausibly get a runaway effect that results in unimaginably intelligent beings, which might be capable of efficiently developing new technology and solving the world's problems.

Of course, there are several limitations to consider. Development of AI and intelligence augmentation at that level could turn out to be prohibitively difficult. It's true that AI has come a long way: for example, just a few days ago, the Watson computer program beat the two best Jeopardy! players in the show's history. But it also has a very long way to go: Watson also occasionally gave answers that no thinking person would come up with, like "Toronto" to a question about "U.S. Cities." War and economic downturns could also get in the way. Politicians could intervene and try to halt development of these technologies out of fear (which wouldn't necessarily be unjustified). And even if such an intelligence does arise, there are still practical limits to how quickly it could produce and implement new innovations.

I must admit that the idea of the Singularity holds a certain attraction for me. Even if a god does exist, it probably wouldn't be the sort that grants us an afterlife, so unless science can come up with some radical solutions, I'll almost certainly be faced with permanent death before this century is over. I try as much as possible to keep my desire for some sort of utopian technological revolution from influencing my analysis of the likelihood of that outcome, but it's tough. Ultimately, the best position to take is cautious, skeptical optimism. I'll hope for a future paradise, but we're nowhere near there yet, so I won't count on it.

Sunday, February 20, 2011

Ebon Musings & Daylight Atheism

The Ebon Musings website (including the accompanying Daylight Atheism blog) is probably the best resource on skepticism and nonbelief that I've come across on the internet. The author, one Adam Lee (aka Ebonmuse), has produced some of the most thoughtful, even-handed and intelligent writing I've read.

Ebon has written on subjects ranging from the nature of religious faith to evolution to secular ethics to Bible contradictions to the existence of the soul and everything in between. He also has an impressively thorough refutation of a Christian book I read by Lee Strobel, The Case for a Creator. There were lots of assertions in that book that sounded fishy to me, and that series often makes clear exactly what's wrong with them. His list of "must-read posts" can be found here (the link to posts of past years is at the bottom of the page).

What I like most about Ebon Musings and Daylight Atheism is how incredibly reasonable they are. Even if an unexpected tidal wave of evidence caused me to convert back to Christianity, I would still have to admit that Ebon was right on a number of major points, and he would still be far more cordial and display far better reasoning skills than most apologists. I don't agree with him across the board, of course, but some of his arguments against theism and Christianity are among the strongest I've come across. Anyone seeking to counter the claims of nonbelievers will run into serious problems here.

Saturday, February 19, 2011

God and His Ant Farm

The Christian God is supposed to be an absolutely supreme being. He knows everything that can be known and can do anything that can be done. Doesn't it seem odd, then, that he would waste his time with us? Christians often express awe at this idea, but then take it no further, never bothering to question why this should be the case. But think about this scenario from God's point of view. Here is this unfathomably complex and intelligent being, who could literally do whatever he wants. Yet he's just so incredibly, ridiculously interested in what from his perspective would be creatures no more clever or significant than ants in an ant farm.

God's fixation on this ant farm of his teeters on the brink of creepy, then plunges right in. Just look at the Old Testament: he's obsessed with even the tiniest minutiae in the lives of his pets. When there are too many "evil" ants, he floods the entire farm with water, drowning all the ants except a few, which he places back into the farm once it dries again. He becomes enraged when one ant mates with another of the same gender. Oh, and did you just give birth to larvae? Got damaged ant genitals? "Ritually unclean" in any other way? Well then you can just forget about coming into the presence of the Almighty, you disgusting little ant you.

Then later on, in the New Testament, he announces he wants to establish a relationship with each and every ant in the farm. He carefully crafts a tiny ant "avatar" and uses it to try and teach the other ants. After the ant avatar's death and resurrection, he promises to one day return and judge the whole farm. Those who believe in the ant-God will be put in a new farm with lots of yummy fruit and get to worship him forever and ever. Those who don't will suffer for all eternity under the burning sunlight refracted from a magnifying glass.

I hope this has illustrated the absurdity of an all-knowing, all-powerful God being as consumed with our every behavioral quirk as the Bible claims him to be, but here's one more idea to complete the image. In the Bible God claims to be the only one of his kind, but hey, for all we know he's just trying to make himself seem more important. Sometimes I imagine God as just one of a great many "supreme" beings. The rest of these beings go about their daily lives much as we do, and they look on our "God" much as we would look on an emotionally stunted man obsessed with his ant farm: with a combination of revulsion and pity. But hey, at least he has his ants to worship him, right?

Thursday, February 17, 2011

WEIT: Cetacean Evolution

Coyne begins his section on whale fossils (pp. 47–52) with a jab from Duane Gish, a creationist infamous for his shallow but confrontational style. During a presentation, Gish showed an illustration of a creature with a fish's back half and a cow's front half, in an attempt to ridicule the transition from land mammals to whales. But Coyne points out that the closest living relatives to cetaceans are hippopatamuses – perfectly reasonable-looking four-legged mammals that spend much their time in the water. It's easy to imagine them evolving into fully aquatic, whale-like creatures with the right selective pressure.

The ancestors of cetaceans were small, furry four-legged mammals such as Indohyus and Pakicetus. We know Indohyus spent a lot of time in the water, because:
"Its bones were denser than those of fully terrestrial mammals, which kept the creature from bobbing about in the water, and because the isotopes extracted from its teeth show that it absorbed a lot of oxygen from water."
Next comes Ambulocetus, a very nice transitional between land and water-dwellers. Creationists often claim we lack the crucial pelvic bones for Ambulocetus. Below is the original fossil – with pelvis – and a reconstruction of its full skeleton (from discoverer Hans Thweissen's website), as well as an artist's depiction of what it may have looked like.

Rodhocetus is even more whale-like, and Basilosaurus and Dorudon are very similar to modern whales. The latter two had greatly reduced hindlimbs; "the fifty-foot Dorudon had legs only two feet long." Page 50 has a great image of how these creatures represent a gradual shift in skeletal structure from land mammals to whales. However, as Coyne points out, it's important to realize (and creationists often ignore this) that these animals didn't necessarily form a direct lineage. Because evolution produces a "bushy" pattern of speciation, many of them were merely cousins of the ancestors of modern whales – and that's okay, because we can still learn a great deal from them.

Finally, Coyne answers the question of why whales might have evolved from land mammals.
"One possibility involves the disappearance of the dinosaurs along with their fierce marine cousins, the fish-eating mosasaurs, ichtyosaurs, and plesiosaurs. These creatures would not only have competed with aquatic mammals for food, but probably made a meal of them. With their reptilian competitors extinct, the ancestors of whales may have found an open niche, free from predators and loaded with food. The sea was ripe for invasion. All of its benefits were only a few mutations away."
This explanation makes quite a bit of sense. Since there were still plenty of predators on land, it's only natural that the ability to stay in the water for long periods to escape them would be heavily selected for.

There's also a wide variety of other evidence for cetacean evolution from other fields of study, but that's covered in later chapters of the book.

Tuesday, February 15, 2011

Why Believers Think Prayer Works

Christians believe that their pleas to God have a tangible effect on the real world. Why do they believe this if it isn't true (aside from the obvious answer of "their religion says so")? Even Christians themselves should be curious about the underlying reasons for belief in prayer—after all, people of other faiths think prayers to their gods are effective as well. In fact, there are quite a few reasons, all of which are quite fascinating.

1. Placebo effect: Say that a believer wants to do well on a test or run their fastest time in the 100-meter dash. If they pray for that outcome, or know that others are praying similarly, they're likely to do better than they would have otherwise, simply because they believe prayer will work. Even in cases that are beyond conscious control, such as quick recovery from an illness, the mere belief that one will recover quickly—whether due to prayer or a sugar pill—is enough to increase one's immune function and spur a faster recovery. The placebo effect may sound incredible, but it's actually one of the most powerful and well-documented psychological phenomena in existence.

2. Regression fallacy: Everyone knows that life has its ups and downs, but when are believers are most likely to pray? Naturally, they will tend to pray more when things are bad, and to pray the most when things hit rock bottom. And since this point is rock bottom, their situation can only get better from there by definition. But because the believer has just been praying so much, they will often attribute the improvement to prayer, even though things would have gotten better anyway. This idea is so simple that it's easily overlooked, but it explains a great deal.

3. Bandwagon effect: People tend to believe things because other people around them believe those things. Believers often belong to a church and are surrounded by people who believe that prayer works. Thus, they are more likely to believe the same. Even if they begin to have doubts about the efficacy of prayer, seeing the strong belief that others have in it will strengthen their own belief. Note that this self-reinforcing effect allows the belief of the entire group to be sustained, even if the belief of every individual within that group occasionally falters.

4. Wishful thinking: This is another simple yet powerful concept: people are more likely to believe things that they want to be true. The idea that a supreme being can not only hear you anywhere at any time, but can also respond to you and act upon the physical world on your behalf, is incredibly appealing. Conversely, the idea that you are often alone and powerless in the world is highly unpleasant.

5. Confirmation bias: People tend to favor information that supports their existing beliefs. This is a massive factor in understanding believers' perceptions of prayer, and it comes into play in two ways. The first is known as "selective recall." In this case, it means that believers will generally remember answered prayers and forget about unanswered ones. The more unlikely the answered prayer, the more likely it will be to stick in their minds. In this way, instances of allegedly answered prayer seem to occur more often than they really do.

The second point follows from the first: believers will tend to tell other people about answered prayers (and tend not to tell them about unanswered ones). Again, the more improbable the answered prayer, the more likely they are to tell others. Those people then tell other people, who tell others, and so on (and remember, selective recall rears its head at every step). The overall effect is that even though extraordinary examples of "answered" prayer occur only very rarely, they will tend to be heavily reported, so that such examples appear to happen relatively often.

6. Sampling bias: Believers are biased in selecting what they will pray for: they usually pray for things that are likely to happen anyway. They might pray for it not to rain during the few hours that an outdoor party or sporting event takes place. If it doesn't rain, they will interpret this as an answered prayer—even if rain was unlikely during that particular interval. On the other hand, if a family member's legs are amputated following an accident, even fervent believers probably wouldn't pray for those limbs to miraculously grow back. By limiting their prayers in this way, believers tend to get what they expect by purely ordinary means.

7. Postdiction: Among other things, this refers to reinterpreting a prediction after the fact to make it fit with the events that occurred. It's more often associated with alleged prophecies, but it applies to prayer as well. Say a believer goes on a date and prays that they will meet the love of their life, and eventually they end up being very good friends, but nothing more. Although the believer was praying about meeting their future spouse, they may consider their prayer answered—after all, they did end up "loving" this person, but in a different way. Because the criteria that believers use to judge whether they got what they "wanted" are actually much broader than they seem, prayers are more likely to be "answered" purely by chance.

8. The last resort: "God answers all prayers, but sometimes he answers 'no'." This is the one explanation that will never, ever fail. It's completely unfalsifiable—that is, as long as believers put stock in this answer, they will never even consider the possibility that there might not be anyone listening.

The idea is that God only answers prayers that align with his will. There are multiple problems with this. First, it seems to contradict certain verses in the Bible. Matthew 7:7 says, "Ask and it will be given to you." John 14:14 says, "You may ask me for anything in my name, and I will do it." There are no qualifications for these statements, and the context doesn't seem to change the meaning. Believers may argue that Jesus meant to say "I will do it if it's God's will," but that's certainly not what he actually says.

Second, there is the problem of evil issue. Famine, disease, and horrible disasters occur regularly, in spite of prayer and for no apparent reason. Innocent children are forced to become soldiers and sex slaves, again in spite of prayer. Why wouldn't it align with God's will to answer these prayers? In such cases believers can only appeal to omniscience, assuming without evidence that God has some unknown reason for allowing these things to happen.

Finally, If Christian believers still think this last-resort explanation is a good one, I must point out that Muslims, Hindus, and other believers undoubtedly think the same way. Do Christians think these people are justified in thinking that their gods answer prayer in this way, even though this reasoning will probably cause them to continue believing in their false gods? If Christians are justified and other believers aren't, why the double standard? The knee-jerk response is "because we're right," but this is mere assertion—and one that those of other faiths could again use just as easily.

Given the many cognitive biases I have covered here, it's not surprising that believers think prayer is effective. The placebo effect, the regression fallacy, the bandwagon effect, wishful thinking, confirmation bias, selection bias, postdiction, and the ever-lurking last resort explanation all work in concert to form the potent illusion of a supernatural phenomenon. We have many excellent explanations for why prayers may appear to be answered. The onus is on believers to show that they truly are.

Note: It's worth mentioning that we actually have scientific evidence that prayer doesn't work. In the most rigorous experiments on the subject, sick individuals who don't know they are being prayed for (to rule out the placebo effect) fare no better than those who aren't being prayed for at all. Faced with this information, believers now have an even greater hill to climb if they are to show that prayer really is somehow effective.

Sunday, February 13, 2011


Evolutionary biologist and atheist PZ Myers runs a blog called Pharyngula. He frequently comments on current events relating to both creation/evolution and theism/atheism. It's updated several times a day and tends to be very up to date in the topics it addresses.

Here are a few examples of what I like about his content: he's dismantled creationist misinterpretations of science, pointed out serious flaws in a study on the efficacy of prayer, repeatedly shown that Hitler was not motivated by evolution or atheism (as many Christians claim), and become infamous to Catholics for deriding their doctrine of transubstantiation. While this rant about the absurdity of a young earth would probably be handwaved as "presumptuous" by YECs, I enjoy it because it showcases just how much evidence they have to ignore to maintain their beliefs. He's made a lot of great posts, but if I had to point to one example of his best work, it would be this devastating refutation of creationist Jonathan Wells' claims about Haeckel's embryos in the book Icons of Evolution.

I do tend to disagree with PZ somewhat when it comes to politics (he's a staunch liberal, while I'm more of a moderate). And while I disagree with accomodationists who think that science and religion should be best buddies, I also find his approach to creationism and theism a little too aggressive. He's fond of mockery and thinks it can be a powerful tool for dislodging people from their status quo beliefs. That's true to an extent, but I think sometimes he goes overboard and makes people more likely to become entrenched in their beliefs and demonize outsiders without considering what they have to say.

Overall, while I somewhat dislike PZ's brashness and some of his political views, I appreciate Pharyngula for its humor, informativeness, and frequent updates on current events.

Friday, February 11, 2011

It's (Still) Not Just Me

I'm getting a little tired of covering O'Reilly's comments on God, but I felt like I should mention a few of the other responses he's gotten. Theoretical astrophysicist Ethan Siegel has some very nice answers (complete with illustrations) for Bill's ignorant questions. Late night talk show host Conan O'Brien also had a joke about Bill's line of reasoning:
"Bill O'Reilly said the ocean tides could only be explained by God. Then, when told they were caused by the moon, he said, 'Then how did the moon get there?' In a related story, Bill O'Reilly is a five-year-old boy."
It's funny, but at the same time a little depressing, since that really is roughly his level of discourse on the subject. Finally, Stephen Colbert weighs in again (starting at 2:25 below):

Around the 4-minute mark Colbert points out something I missed—namely, that Bill asked why Earth has a moon and Mars doesn't, but Mars actually has two moons, Phobos and Deimos. The rest is mostly mockery – which is totally okay. When an argument is just too dumb, and the arguer isn't going to be persuaded by reason, that's often the best response.

Wednesday, February 9, 2011

JI: On What Day Was Jesus Crucified?

The first major Bible contradiction Ehrman covers in Jesus, Interrupted is on pages 23–28. He starts by reminding readers that for the Jews, each new day began at sundown, around 6pm. So here's the contradiction: The synoptic gospels (Matthew, Mark and Luke) say the Last Supper was the Passover meal, and Jesus was crucified the next morning (still Passover). But John says the Last Supper was eaten the day before Passover, called the Day of Preparation, and Jesus was crucified the next afternoon (still the Day of Preparation).

Here's what Mark 14:12, 17-18 says:
"Now on the first day of Unleavened Bread, when they killed the Passover lamb, His disciples said to Him, 'Where do You want us to go and prepare, that You may eat the Passover?' ... In the evening He came with the twelve. Now as they sat and ate, Jesus said, 'Assuredly, I say to you, one of you who eats with Me will betray Me.' "
The disciples killed the lamb on the Day of Preparation. After the sun went down in the evening, it became Passover and they ate the Passover meal. Matthew 26:17-21 and Luke 22:7-16 confirm this view, but John is a different story altogether. First, here's Ehrman's commentary about what what John doesn't say:
"But it is striking that in John, at the beginning of the account, in contrast to [the synoptics], the disciples do not ask Jesus where they are 'to prepare the Passover.' Consequently, he gives them no instructions for preparing the meal."
So all three synoptic gospels have Jesus and the disciples explicitly stating that this is the Passover meal, while they do no such thing in John. Already something's a little fishy; John may have purposely left out this part, for reasons I'll cover later. Now let's look at the other evidence. John 13:1-2 is ambiguous: the phrase "before the Feast of the Passover" could easily refer to the "supper," but it's also plausible that it doesn't. But other verses show that in John's view, this is not the Passover meal and that Jesus was crucified on the Day of Preparation:
"Now after the piece of bread, Satan entered into him [Judas]. Then Jesus said to him, 'What you do, do quickly.' But no one at the table knew for what reason He had said this to him. For some thought, because Judas had the money box, that Jesus said to him, 'Buy those things we need for the feast,' or that he should give something to the poor." (John 13:27-29)
Here the disciples have just finished the Last Supper, and some of them think Jesus is sending Judas to buy food for the Passover feast.
"Then they led Jesus from Caiaphus to the Praetorium, and it was early morning. But they did not go into the Praetorium, lest they should be defiled, but that they might eat the Passover." (John 18:28)
Here it is the next morning (in the same Jewish day), Jesus is being led to Pilate's residence to be judged, and the priests have not yet eaten the Passover.
"Now it was the Preparation Day of the Passover, and about the sixth hour. And he [Pilate] said to the Jews, 'Behold your King!' " (John 19:14)
This verse makes the problem abundantly clear. Matthew, Mark and Luke say that Jesus had the Last Supper on Passover. It's now "the sixth hour" (i.e. noon) later in the same Jewish day, Jesus is being judged, and John is telling us that it's the Day of Preparation! However, there's still one more piece of evidence that I think seals the deal for this contradiction. Here's what Ehrman has to say about it:
"John is the only Gospel that indicates that Jesus is 'the lamb of God who takes away the sins of the world.' This is declared by John the Baptist [in John 1:29, 36]. Why, then did John—our latest Gospel—change the day and time when Jesus died? It may be because in John's Gospel, Jesus is the Passover Lamb, whose sacrifice brings salvation from sins. Exactly like the Passover Lamb, Jesus has to die on the day (the Day of Preparation) and time (sometime after noon) when the Passover lambs were being slaughtered in the Temple.
"In other words, John has changed a historical datum in order to make a theological point: Jesus is the sacrificial lamb."
Is it just coincidence that John perfectly times Jesus' death to coincide with the slaughter of the Passover lambs? It's possible, but I think that's quite unlikely, especially in light of the other evidence. Speaking of which, let's review:
  1. All three synoptics have Jesus and the disciples referring to the Last Supper as the Passover meal. John does not.
  2. John has three passages after the Last Supper indicating that the Passover meal had not yet occurred.
  3. John places Jesus' crucifixion at the same day and time as Passover lambs were being killed, implying he fudged the facts to create a metaphor.
Remarkably, Christians can't even agree among themselves on the right solution to this problem. Some claim the Last Supper and crucifixion fell on the Day of Preparation (as in John). Others claim the Last Supper was the Passover meal, and Jesus was crucified on Passover (as in the synoptics). Both sides believe they are obviously right. One would think the Holy Spirit that supposedly dwells in them would help them all interpret things the right way, but apparently not. In the end, their arguments largely cancel each other out, and I must conclude that this is a very real contradiction.

Monday, February 7, 2011

A Creationist Examines Human Tails

First, a bit of background. Human tails are an atavism: the reappearance of an ancestral trait in certain individuals after many generations. Atavisms are an important piece of evidence for evolution because they help show how various animal species diverged. In particular, human tails represent the resurgence of the more robust tail of earlier primates. There are other examples of atavisms that I find more exciting than human tails (for example, whale legs), but it's still quite an interesting phenomenon.

Now, a few months ago I found an article by Andrew Lamb on the Creation Ministries International website entitled "Human tails and fairy tales," which disputes information presented in Douglas Theobald's "29+ Evidences for Macroevolution." Theobald discusses instances of "true human tails" containing vertebrae and presents an x-ray from a scientific paper as visual proof.

Lamb, however, claims that the coccyxes of the children described in the paper are in fact perfectly normal:
"In fact that x-ray shows a normal healthy spine, as admitted in the original research paper by Bar-Maor et al. from which that x-ray image (Figure 3 in the paper) was taken."
I was taken aback by Lamb's assertion, and began to wonder if Theobald's excellent article was not as accurate as I had thought. I decided to investigate, and found that in fact Theobald was correct and Lamb was completely wrong. If Lamb read the paper to its conclusion, he should have seen that:
"Our first patient had no obvious coccygeal protuberance, but the coccygeal anomaly was well evident on radiographs as a tail-like structure and was the cause of his coccygodynia. This anomaly could be described in Bartels' traditional classification as 'a bony tail caused by hypertrophy of the sacrococcygeal vertebrae'. Our second and third patients had almost similar radiological findings, but in addition they had soft protuberances."
Does Lamb consider the phrases "coccygeal anomaly," "bony tail," and "hypertrophy of the sacrococcygeal vertebrae" consistent with idea that the three children's coccyxes were normal and healthy? Lamb also comments:
"Alarmingly, despite Child 2's coccyx being normal and healthy, the Bar-Maor paper goes on to say that part of the coccyx was removed during the surgery[.]"
Yes, it would be alarming, wouldn't it… if the paper gave any indication that the child's coccyx was in fact normal.

I'll grant that the paper's use of the phrase "well-developed" to describe the vertebrae could be taken to mean "developed correctly" rather than "over-developed." However, this paper isn't much more than 2 pages long. How could Lamb have missed the entire paragraph quoted above – not to mention a description of one of the coccyxes as "very prominent"?

Perhaps Lamb has expertise in anatomy, and in his professional opinion the x-rays appear normal? Nope. A quick look at his biography page shows that he only has degrees in education and computer science – no such expertise to be found. It's difficult to tell whether Lamb was intentionally deceptive or simply incompetent in his response, but to give him the benefit of the doubt I'll assume the latter.

Through this experience, I gained a fuller understanding of atavistic human tails. But more generally, it really impressed on me the importance of investigating controversial claims, especially when they come from heavily biased sources like CMI.

Friday, February 4, 2011

The Stupid, It Burns...

In two previous posts I covered Bill O'Reilly's ridiculous arguments for a creator. I happened upon a YouTube video where he responds to someone who points out that we do in fact know how tides work. He does so by smugly asking a bunch more science questions and declaring unbelievers "desperate." Of course, it takes far less time to ask these questions than to answer them, so believers could easily gain a false sense of confidence from a response like this one.

First I'll point out the obvious: once again, many of the phenomena O'Reilly refers to have already been explained by scientists. We have a fairly good idea of how the sun and the moon formed. We aren't yet sure how life first began (though we have several hypotheses), but abiogenesis is a difficult and fairly new field of study, so that's not at all surprising. As for why there's life here as opposed to elsewhere, Earth happens to be a Goldilocks planet; it's simply a matter of having the right conditions.

But this is all moot, because in Bill's mind, the best solution is clearly to posit an all-powerful being who magically answers all of our questions. Naturally it doesn't occur to him that this is a classic example of the "God of the gaps" fallacy: we can't yet explain X, therefore God did it. Richard Dawkins said it very well in a discussion with O'Reilly back in 2009: "it's the most extraordinary piece of warped logic to say that because science can't answer a particular question, you're going to throw in your lot with Jesus."

What I thought was especially funny (and sad) about this video is that O'Reilly actually sounds annoyed that we can explain the tides. To him, this fact is not a valuable piece of knowledge, but an obstacle to his wonderment. If all of us had this mentality, we'd still believe in a sun that revolves around a flat earth. O'Reilly just doesn't seem to understand that the gaps in our knowledge are closing, that we're slowly but steadily explaining all the phenomena that were once attributed to God. Given this trend, why should we expect the currently unexplained information to be any different?

Wednesday, February 2, 2011

WEIT: Tetrapod and Bird Evolution

On pages 35–47 of WEIT, Coyne talks about the evolution of tetrapods and birds. Tiktaalik roseae is a great example of a "fishapod": it has scales, gills and fins like a fish, but ribs, lungs, and a neck like a tetrapod. It also has ears and wrist and finger bones that are intermediate between fish and tetrapods. Below is Tiktaalik along with some similar creatures, most of which represent other parts of the "out of the water" evolutionary phase.

How did these traits come about? Being able to temporarily crawl up on land conferred a massive advantage to creatures like Tiktaalik because it helped them escape from predators. They used their fin-limbs to push themselves up onto land, and their lungs and ribs allowed them to breathe air. Coyne also points out that the position of their nostrils and eyes at the top of the head would have allowed them to both look and breathe just above the water's surface.

Next up is Archaeopteryx, a feathered dinosaur-like creature that is a close relative of the common ancestor of all birds. Oddly enough, creationists try to claim it's fully bird – probably because at first glance it looks like a bird (see fossil and reconstruction below). However, in fact it has far more reptilian traits (e.g. teeth, claws, 6 vertebrae, a bony tail) than avian ones (e.g. feathers, opposable big toe). On page 41 Coyne has a great illustration demonstrating Archeopteryx's similarity to both the dinosaur Compsothagnus and a modern chicken. Coyne also mentions Mei long, a dinosaur fossilized in a "roosting" position with its head under its wing-like arm, showing that birds and dinosaurs are linked in behavior as well as form.

Coyne also answers creationist questions about how wings evolved ("what good is half a wing?"). Scientists have proposed that feathers may have evolved from reptilian scales as a form of insulation. From there, the ability to glide evolved before the ability to fly. Two major models have been proposed. Under the "trees down" model, theropod dinosaurs (which likely lived partially in trees) used gliding to cushion falls, escape predators or catch prey. Under the "ground up" model, they used their wings to get off the ground for short distances or to help scale steep uphill slopes.

These two groups of examples barely scratch the surface of the fossil evidence for evolution. I'll summarize more of the evidence Coyne presents in later posts.