The Learning Annex is a privately owned continuing-education school in New York. As a resident of New York City, I can testify to its success - its kiosks of free course catalogs are on nearly every street corner in Manhattan. It was founded in 1980 by Bill Zanker, who sold the company in 1991 and then repurchased it and resumed ownership in 2002. The 2007 Inc. 500, a list of the nation's fastest-growing private companies, ranked the Learning Annex at number 346 and said that it makes over $100 million in revenue in each year.

On my lunch break last week, I picked up a Learning Annex catalog and flipped through it. Some of its offered courses are about professional software, how to found a small business, how to interview for a job, or other serious topics. Others are about dating, diet, or other self-help topics. But a great many of them are straight-up pseudoscience. A large number of Learning Annex classes promise to teach students how to develop their psychic powers, how to get rich or find the perfect spouse using the "Law of Attraction" (the Law of Attraction is a very popular course topic), how to communicate with dead relatives, how to "reverse the aging process", how to heal using qi gong, how to improve your life with neurolinguistic programming (for the jaw-dropping price of $2500), and many more.

As a private business, the Learning Annex profits by people signing up to take its courses, so they have little reason to turn away anyone who offers to teach a class. This no doubt accounts for much of the bottom-feeding superstition in these pages. There are many self-deluded people who are eager to share their credulity with the world, and of course it's much easier to claim to be a teacher of psychic powers than to be a teacher of Photoshop. One requires actual skill and education, while the other thrives on a lack of any discernible qualifications or results. The mantle of "psychic teacher" can be worn by any charlatan; if they've published a book or run a website, so much the better.

But it goes far beyond that. The Learning Annex, far from passively putting up with these miracle-mongers, actively works to promote them and boasts about their presence. The first page of its catalogue, as well as a later full-page ad, prominently advertises a webcast by noted psychic failure and free-speech enemy Sylvia Browne. The Browne webcast is presented as a tie-in for the launch of their own new pseudoscience-themed site, SpiritNow.com, whose index page is a gleeful mishmash of astrology, angels, psychics and feng shui. The back page of the catalogue, meanwhile, advertises a course taught by TV psychic Char Margolis.

Purely on an economic level, it's hard to fault the Learning Annex. No doubt they, like much of the media, have found that peddling pseudoscience is a great way to rake in the bucks. Marketing to skeptics is an endeavor that some might say suffers from an intrinsic contradiction. But the credulous are huge in number and eager to be exploited.

But the problem with pandering to superstition is that, inevitably, it degrades one's seriousness and credibility. The more this nonsense infects its pages, the more the Learning Annex will lose what real educators it has. After all, if you're a genuine, credible expert on some important topic, why make yourself a laughingstock by sharing space with fly-by-night psychics, people who talk to angels, and hawkers of the latest get-rich-quick scams? Pseudoscience, like water, seeks its own level. Before long, if they continue at this pace, this is all the Learning Annex will have left - just one more outlet for every brand of nonsense our society has to offer.

Every educational institution has to confront the fact, at some point, that real teaching is a difficult, expensive business. It's certainly possible to succeed doing it legitimately, but the temptation will always be there to lower the standards, throw open the gates, and make the easy money from people who flock to have their superstitions catered to and their prejudices reinforced. "What's the harm?" is the usual rationalization - a rhetorical question which can be answered by noting that the harm, though subtle at first, is very real indeed. It consists in sending the message that pseudoscience is a legitimate area of study, worthy of being put on a par with genuine science. Inevitably, science suffers from that equation.

Over the past two months, I've written about the differing epistemologies of religion - where the individual's personal conviction is taken as a reliable guide to truth ("The Aura of Infallibility") - and science - where the assumption is that individuals are fallible and should work as a group to correct each other in a spirit of free inquiry ("Self-Correction").

The question I now want to turn to is this: How does a lay person tell the difference? Why should people who are not particularly educated in either religion or science - which is most people, after all - choose one over the other? More important, from our perspective, what reason do they have to make the right choice? Looking up "from the ground" at the two mountain peaks of science and religion, how can they tell them apart?

As we know well, science has far better evidence in support of its hypotheses. But to most people, examining both religion and science in the degree of detail needed to confirm that would be an enormous endeavor. And to what end? To decide an abstract philosophical point? It's no wonder that most people stay in the faith they're brought up in. Even if they wanted to find a different system of thought, just getting started might seem like an overwhelmingly difficult task.

From the outside, all belief systems seem similar. Creationists and other pseudoscientists often exploit this confusion. If they can put a man in a suit with letters after his name on stage, to argue against a different man in a suit with different letters, the audience will often assume both sides must be equally matched - even if what the creationist is saying is total nonsense to anyone who actually knows anything about the field being discussed.

So, what reason would a nonexpert have to choose science over religion as a way of understanding the world? I have three reasons to offer that even an outsider can appreciate:

• Science has a clear trend of progress. If, after several centuries or millennia, scientists were still divided into numerous squabbling camps, fruitlessly arguing over issues that had been in dispute since the beginning - then we might have reason to doubt that science produces an accurate view of the world.

But science, as any person can see, is not like this. Scientific disputes and arguments do occur, of course; but after enough time has passed and enough evidence has been gathered, they are settled, and science moves on. No camp of scientists is still arguing against quantum mechanics, or the heliocentric solar system, or continental drift. Those disputes have been settled, and science has moved on. (There is still a tiny minority of dissenters to the theory of evolution, but even here the exception proves the rule: these dissenters are motivated first and foremost by religious beliefs.) Today, scientists are arguing about the nature of dark matter, and whether Homo floresiensis is a separate species of human, and what the precise effects of global warming will be on the world's climate. If history is any guide, then doubtless in a few decades these controversies will be settled, and scientists will be considering other new problems.

This progressive process, this building upon past achievements, is the unique hallmark of science as a way of knowing. Unlike religion, science solves problems. Rather than fracturing into perpetually warring sects, science over time becomes more unified, not less, as it steadily increases the number of areas in which consensus has been achieved. This alone should give us confidence that science is actually discovering something real - the true nature of the physical world - as opposed to enshrining the varying products of human imagination.

• Science has built-in methods of self-correction. It can't be overstated that science has a way of overthrowing prevailing wisdom built right in. Everyone is free to submit their evidence and arguments to the review of their peers. There is no central authority who decides what scientists must believe, or what statements may not be questioned. This method has worked well since the scientific revolution, continually updating old and mistaken ideas with new and more accurate descriptions of the way the world works.

When religions undergo correction, by contrast, it is always imposed on them from the outside. Search history for an example of the theologians and authorities of a religious sect being persuaded through rational debate that one of their doctrines was wrong, and then agreeing to change it. I doubt you'll find one. Instead, change in religion occurs when a small group of people declares that the prevailing wisdom is wrong. Inevitably, they are met with ridicule, suppression, and often violence from the established theological authorities. (By contrast, try to find two groups of scientists who went to war over some disputed theory.) Often, this process leads to the factioning of new sects and the beginning of a new round of religious warfare. (See last point.) Sometimes, when society's consensus becomes too overwhelming to ignore, sects' official dogmas do change - although, again, it's usually the authorities who are the last to give way. This dogmatic attitude, unlike the self-correcting humility of science, is far less likely to detect whatever errors there may be in a sect's view of the world.

• Science can demonstrate accomplishment. Even to the uneducated, it should be clear that science works. Through scientific research, we have produced a steady stream of inventions and achievements which people of a few centuries ago - or even a few decades ago - would have considered near-miraculous. In just a few centuries, science has taken the human species from wooden sailing ships to transcontinental flight and space travel; from flint and tinder to nuclear fission; from the four bodily humors to transplant surgery and gene therapy.

By contrast, the accomplishments of religion are non-existent. What advances have come about in two millennia and more of prayer and theology? More potent faith healing? More effective prayers, with a markedly improved response rate? More and better prophets who can do more and better miracles? Forgiveness for sins that could not previously be forgiven? No, religion is in the same place it always was, and is still offering the same explanations for why its beliefs and practices fail to have any measurable, tangible effect on the world around us. If religion had anything like the level of accomplishment of science, people would regularly be flying to Heaven and visiting God in person by now.

Via Reuters, a story out of the U.K. that made me very happy indeed: British "psychics" are protesting a new consumer-protection law which they fear will require them to offer actual proof of their alleged powers.

The law currently in force in this area is the Fraudulent Mediums Act of 1951, which does in fact make it illegal to fraudulently claim to possess psychic or clairvoyant powers. But the key word is "fraudulently" - meaning that any enterprising prosecutor would have to prove that not only that the defendant has no psychic powers, but that they were aware of this and deliberately set out to deceive. This is a high bar to surmount, which is why the Act has hardly ever been used to prosecute psychic claimants. (Oddly enough, Northern Ireland is specifically exempted. I guess fraudulent psychics working there luck out?)

But now, as part of an effort to harmonize consumer-protection laws across the European Union, the Act may be repealed. The new regulations proposed to replace it ban "treating consumers unfairly", and psychics worry that this language could be used against them, to force them to prove their claims are genuine. Gee, you think?

Organizers [of the petition drive] say that replacing the Fraudulent Mediums Act of 1951 with new consumer protection rules will remove key legal protection for "genuine" mediums.

They think skeptics might bring malicious prosecutions to force spiritualists to prove in court that they can heal people, see into the future or talk to the dead.

Excuse me - "malicious" prosecutions? How on earth would that be malicious? If a psychic is the real thing, surely there can be no harm in asking them to prove this in clear and convincing fashion with objective evidence. If a psychic is phony, and the practitioner is duping the gullible with false claims, why would it be malicious to prosecute them for this? Any other business that uses false claims in its advertising is liable to prosecution. Why should psychics get a special exemption from that ordinary and reasonable standard?

Here's the answer that gives the game away:

"If I'm giving a healing to someone, I don't want to have to stand there and say I don't believe in what I'm doing," said Carole McEntee-Taylor, a healer who co-founded the Spiritual Workers Association.

..."By repealing the Act, the onus will go round the other way and we will have to prove we are genuine," McEntee-Taylor told Reuters. "No other religion has to do that."

No other religion has to do that. Clearly, the psychics see themselves not as businesspeople, but as religious practitioners - and as such, they believe they should be exempt from having to present proof. Because, of course, anything that is "religion" does not need to present any proof for its claims, and it is unfair to ask otherwise. This is exactly what atheists like Sam Harris are speaking of when they refer to the corrosive, dangerous effects of faith, in that it elevates ordinary claims above the necessity of testing and criticism.

But I do agree that it would be unfair to ask psychics to offer proof of their powers while exempting other religions. So, let's take this even further! Any supernatural belief system that claims to offer tangible benefits - healing, prosperity, discerning the future - should be put to the test and have to prove that it can deliver on its claims, the same way as any other business which sells a product. It's insane that anyone who makes a specific claim to be able to deliver services in exchange for money can avoid any kind of testing or scrutiny by slapping the label "religion" on his business.

As I wrote in "A Call for Truth in Advertising Laws", many religious frauds make explicit, specific claims about what they can deliver. Real businesses, as opposed to businesses selling superstition and pseudoscience, never get away with this. No legitimate pharmaceutical company can claim its drugs can cure some illness unless it goes through multiple rounds of double-blind testing to prove this. Food companies can't claim their products can prevent heart disease unless there are well-designed studies to show it.

Why should psychics and miracle-hawkers be held to a different standard? Why not make faith healers and psychic surgeons go through double-blind studies that track recovery rates? Why not put cold-readers and mediums to the test? Present them with five unknown people, whom they cannot see and who do not give feedback, and ask the psychic to perform a reading for just one - then have the five separately rate that reading's accuracy to see if it applies well to only one of them. Why not see if clairvoyants can read the symbols on Zener cards and check if they can do any better than the 20% rate chance would suggest?

The possibilities are limitless, and it's no wonder psychics are terrified. Ask them to actually prove their abilities, as opposed to exploiting the gullible and credulous under poorly controlled conditions, and their whole industry would melt away. Make no mistake, they fear a real test because they know they could not possibly pass. And that makes it all the more imperative that we skeptics push for real tests, to demonstrate that psychic powers are a sham and a delusion, and that their claimants are enriching themselves by shamelessly preying upon and exploiting people who are eager to believe.

"We need to ask ourselves this question: 'Where do we put our faith and trust? In the words of scientists who don't know everything, who were not there? Or in the Word of God — the God who does know everything — and who was there?'"

—Ken Ham, "Were You There?"

I've been reading this stomach-turning story about young-earth creationists taking groups of children on tours of real museums, using the exhibits and displays of real science in the service of lies. This isn't the first time this has happened. Enemies of science like Ken Ham have raised child-brainwashing to a fine art, drilling their young devotees in the art of mindlessly reciting creationist talking points:

Evangelist Ken Ham smiled at the 2,300 elementary students packed into pews, their faces rapt. With dinosaur puppets and silly cartoons, he was training them to reject much of geology, paleontology and evolutionary biology as a sinister tangle of lies.

"Boys and girls," Ham said. If a teacher so much as mentions evolution, or the Big Bang, or an era when dinosaurs ruled the Earth, "you put your hand up and you say, 'Excuse me, were you there?' Can you remember that?"

I have nothing but sympathy for the children whose minds are being poisoned by this evil ignorance. Sadly, many of them will grow up into adults who will carry these tactics forward to the next generation. I routinely get e-mail from creationists using the same "Were you there?" ploy, apparently thinking it's a stumper question.

The distinction which creationists seek to create between present and past events is an artificial one that does not exist in reality. Events that happened in the past and were not directly observed can be scientifically verified. We do it the same way we scientifically verify a claim about a present event: derive testable predictions and go check whether the evidence supports them.

Here's a simple example which I routinely use when creationists ask me this. A man claims he is innocent of murder. There were no witnesses to the crime. However, at the crime scene, we find fingerprints on the murder weapon which match that man's fingers, genetic traces under the victim's fingernails which match his DNA, bite marks on the body which match his teeth, and bloody bootprints which match his shoes. Is the question of this man's guilt or innocence beyond scientific verification, just because the crime was not directly observed?

The same principle applies with evolution. We do not directly witness the past, but we can reconstruct the course of events by examining the traces they leave behind. We date rock layers using radiometric dating and other methods; embedded in those layers, we find fossils which display varying characteristics. We can relate those fossils to earlier or later fossils, as well as species living today, and observe how they have changed over time. From the hypothesis of descent with modification, we derive further predictions (such as the existence of vestigial structures, or shared molecular errors forming nested hierarchies) which we can test in living things.

There is no basis for this bizarre belief that the only way to know how something happened is to directly observe it. If anything, empirical evidence of the past is more reliable than eyewitness testimony. It is amply documented that human beings routinely exaggerate, misremember, confabulate, and lie. Physical evidence of the past is not distorted by deception, by the limits of human imagination, or by the tricks that memory plays.

The creationist argument fatally undermines itself. Creationists like Ham say that, since no human was there when the Earth was created, we can't really know what happened and must rely on the words of God, who supposedly was there. But how do we know God was there? After all, we weren't there! Creationists who say the Bible is infallible weren't there to see it written, so how do they know who wrote it? How do they know it was written by someone with any knowledge of the events it relates?

What the creationist argument comes down to is that we should believe one set of claims about the past rather than another, based on nothing but their unsupported say-so. This assertion is really just the aura of infallibility in a different form.

As you can see from this picture, the building where I live has no thirteenth floor:

But of course, what this picture depicts is a mathematical impossibility. My building does have a thirteenth floor; it's just that it's mislabeled as the fourteenth floor, with all the floors above it similarly mislabeled by one.

This may be a small thing, but every time I step into the elevator, it's a jarring reminder of how superstitious beliefs still permeate our society. I can see the logic in, say, a casino mislabeling its thirteenth floor - after all, that business makes money primarily by catering to irrational people. But an apartment building, really? I live in a modern high rise in a well-to-do section of New York, and I can assure my landlords that they would not have difficulty finding people willing to live on the 13th floor.

Numerology and number phobia may be among the oldest of superstitions. Ironically, the specific numbers that are considered "unlucky" vary from culture to culture - in Western societies it's 13 (ironically, Indians consider 13 to be a lucky number), while in Eastern cultures, 4 is usually thought of as unlucky, since it is pronounced similarly to the word for "death". 11 is unlucky in Italy, for a similar reason: the Roman numeral "XVII" can be rearranged to spell "VIXI", which means "I lived". 666, a very unlucky number indeed in Christianity, is lucky in many Eastern cultures. 7 is often considered lucky in the West and 8 in the East, but both of these are unlucky to Buddhists.

The usual accompaniment of unlucky-number superstition is numerology, which can be found among groups from September 11 conspiracy theorists to Jewish devotees of the Kabbalah (who call the practice gematria). All devotees of the practice use the same technique: assigning number values to letters and words, then putting those numbers through an arbitrary series of mathematical transformations until they arrive at some number arbitrarily deemed "significant". A related method is to sort through huge numbers of numerical facts, looking for a number which several of those facts share in common, and assuming that those facts must also be connected.

Since there are literally no rules to this process, and since there are vast pools of numerical data to draw from, it's no surprise that devotees of this method can arrive at whatever numbers they deem to be significant. But the significance is not in the numbers themselves. Like seeing patterns in clouds, the significance is imposed on the numbers by the mind of the observer. This can even be done with apparent mathematical rigor, as in this column from Jane Bryant Quinn:

David Leinweber, an expert in quantitative investment, satirized the "science" of prediction by sifting through numbers to see how he could have forecast the performance of the U.S. stock market from 1981 through 1993. He combined the total volume of butter produced each year in Bangladesh with the number of sheep in the U.S. and a few other variables, to produce a formula that forecast the past with 99 percent accuracy.

If precise, quantitative formulas can be so easily exploited to find seeming significance in patternless numerical noise, it's no surprise that the far less rigorous devotees of numerology can do the same. The mathematician John Allen Paulos, in his recent book Irreligion, has an example of how easily these spurious correlations can be concocted:

Think of any four numbers associated with yourself (your height or weight, the number of children you have, your birthday or anniversary, whatever) and label them X, Y, Z and W. Now consider various products and powers of these numbers. Specifically consider the expression X^a Y^b Z^c W^d, where the exponents a, b, c and d range over the values 0, 1, 2, 3, 4, 5, 1/2, 1/3, 1/4, or the negatives of these numbers.

...Among all these values, there will likely be several that equal, to at least a couple of decimal places, universal constants such as the speed of light, the gravitational constant, Planck's constant, the fine structure constant, the boiling point of carbon, and so on. (p.23)

The astronomer Cornelis de Jager, who came up with this formula, was able to use it to prove that there is a deep connection between the laws of the cosmos and his bicycle: the square of his bike's pedal diameter, multiplied by the square root of the product of the diameters of his bell and light, was 1,836 - the same as the ratio of the mass of a proton to the mass of an electron. A shocking cosmic kismet? Proof of some grander and deeper significance to the manufacturing of Dutch bicycles? Rather, like all numerology, it is simply an example of the law of truly large numbers: although the odds of one particular coincidence are small, given enough data, the odds that some coincidence will occur are very good indeed.

Other posts in this series:

• Popular Delusions

I recently finished watching Planet Earth, the award-winning BBC nature documentary series narrated by David Attenborough. As its title implies, Planet Earth is an effort of considerable ambition: the filmmakers set out to produce a series that would provide a survey of our world's natural grandeur and biodiversity. To a remarkable extent, I think they succeeded. Of course the full richness of Earth's biosphere could not be exhaustively chronicled, but this series touches on many of the high points. It sweeps across every region of the planet, documenting our world's remaining wildernesses and some of the more important species that live in them, in the process filming things that have never been caught on camera before. In its scientific breadth and scope, in the beauty it depicts, and in the reasons it gives us both to fear, and more importantly, to hope, Planet Earth compares favorably to Carl Sagan's Cosmos.

The series consists of eleven episodes, each of which chronicles a different type of ecosystem flourishing on our planet. Over the course of the series, we're taken from icy tundra and boreal forest to tropical jungle, from the rich shallow seas to the blackness of the ocean abyss, from soaring mountains to desolate deserts to the eerie dark worlds of the cave systems beneath the planet's surface. Each episode is fifty minutes, plus a ten-minute ending segment called "Planet Earth Diaries" that shows how some of the more difficult-to-obtain shots were filmed - a nice touch that gives one appreciation for the truly heroic dedication of the photographers who traveled to some of the most remote, wild areas of the planet, braving all manner of harsh and grueling conditions, and worked in some cases for weeks on end just to catch a few moments of action on film. Three additional episodes, collectively titled Planet Earth: The Future, make the case for conservation using footage from the series and interviews with prominent advocates for the environment.

But the focus of the show, as I said, is on the breathtaking natural beauty of our planet and the wonderful, intricate tree of life that flourishes upon it. I couldn't do justice to all the high points in this one post, but here are a few that particularly stood out to me:

• a snow leopard, one of our planet's rarest and most elusive predators, hunting twisted-horned markhor antelope in the Himalayas of eastern Pakistan - the first close-up images of snow leopards in the wild ever filmed;
• the vast precipice of Venezuela's Angel Falls, the world's highest waterfall - a sheer drop of nearly a kilometer, so high that the falling water is blown into mist before it reaches the bottom;
• Nile crocodiles exploding out of the water to grab migrating wildebeest crossing their river - the terrifying tenacity of the bull crocodiles is shown when one of them, after grabbing a wildebeest's leg in its jaws, wrestles with its unlucky prey for over an hour before finally dragging the wildebeest into the water and drowning it;
• parachute divers leaping into the sunlit shaft of Mexico's Cave of Swallows, a dizzying sheer drop deeper than the Empire State Building is tall;
• a male polar bear, starving and exhausted after a long swim in the open water of the melting Arctic, desperately attacking a herd of bull walruses;
• a spectacular sequence in which an entire pride of African lions hunts and kills an elephant;
• the elaborate courtship displays of New Guinean birds of paradise;
• a band of chimpanzees waging war on a rival tribe, slipping silently into their adversaries' territory before erupting in a furious charge of intimidating shrieks and hoots; the savage hand-to-hand fighting ends with the losers being torn apart and, in some cases, devoured by the winners;
• banded sea kraits - aquatic snakes - swimming as smoothly as eels to hunt fish among the coral reefs of the Pacific;
• Borneo's Deer Cave, where a flock of three million bats has created a guano mound the size of a large building, covered with swarming, voracious cockroaches;
• in the Azores, a school of hundreds of dolphins herding scad mackerel, working in unison to encircle their prey and drive them closer to the surface, where diving cory shearwaters soar down to share in the hunt;
• the lush communities of strange life that thrive around hydrothermal vents on the ocean floor, powered by the superheated plumes of mineral-rich water erupting from fissures in the crust, like oases in the abyssal dark. When these vents stop erupting, a whole community can collapse from vibrant life into a dead, frozen forest of tube-worm skeletons - a devastation treated by the film with all the gravity of an empire's fall;
• a vast flock of migrating Baikal teal - hundreds of thousands of birds, all flying in unison - and the camera pulls back, and back, and still further back, until each individual bird is just a tiny speck, and still the whole flock cannot fit on the screen at once;
• and last but not least, time-lapse shots of the seasons changing, even time-lapse shots from space that show rivers flood, forests turn green, snow and glaciers advance - I don't know how these were taken or whether they were special effects.

The one caveat I would offer is that Planet Earth is a nature documentary, which means most of the sequences are of animals doing what animals normally do in the wild. If you're the kind of person who finds that boring, you'll probably be bored by this as well. There are plenty of hair-raising moments, but the purpose of the show is not to keep viewers constantly on the edge of their seat. Personally, I found it a spectacular glimpse of some of the Earth's last remaining places of wild beauty. If that description appeals to you, then I can safely say that you'll love Planet Earth, and I would definitely recommend it.

By now, I assume, the entire blogosphere has heard about the public-relations fiasco which the producers of the creationist film Expelled have brought upon themselves. If you haven't, here's a brief rundown: last week, everyone's favorite fire-breathing atheist blogger and biology professor, P.Z. Myers, went to see an advance screening of the film. It seems only fair that he'd get to see it - he was deceived into appearing in it by the producers, who told him it was going to be called Crossroads and would be an exploration of the relationship between science and religion, not the hardcore anti-science polemic it turned out to be. But while he was standing in line at the theater, he was met by security, who demanded he leave the premises immediately. It turned out the film's producers didn't want him to see it. But in the grandest stroke of irony ever, Myers' guest - who is also interviewed in the film, and whom the producers apparently did not recognize - was allowed in to see it. That guest? Richard Dawkins.

Mark Mathis, the producer of Expelled, has rapidly cycled through excuses in the past several days trying to explain this. First it was alleged that P.Z. Myers was being disruptive (a lie), then it was alleged that he was gate-crashing a private screening (also a lie; there was an open registration on the internet for anyone who wanted to attend). Finally, he seems to have settled on the ad hoc excuse that he simply wanted Myers to pay to see it. Apparently, Mathis is oblivious to the hypocrisy of making a film which asserts that dissenters are being unfairly shut out of scientific discourse, then banning people whom he disagrees with from seeing it and threatening them with arrest if they don't comply. (A post filed on another screening of Expelled reports that Mathis is still threatening people with expulsion for asking too many non-supportive questions. The producers have also tried to make critics sign non-disclosure agreements in an apparent bid to prevent them from writing negative reviews.)

By most accounts, Expelled is a remarkably shoddy piece of filmmaking. Its entire premise is that evolution led directly to the Holocaust, making its case by showing footage of scientists followed by footage of Nazi death camps. Of interest, it also drops the flimsy pretense of intelligent design being "science", instead claiming repeatedly and straightforwardly that ID is religious. The film's strategy of marketing directly to churches and homeschoolers ties in with that. (I really, really hope some Christian group congratulates the film's narrator, Ben Stein, on how many souls his wonderful movie is bringing to Christ. Stein is Jewish, incidentally.)

All in all, this affair has proved to be a wonderful piece of good news for friends of science. This whole affair has made the creationists look like hypocrites, and not only that, it's shone a light on the shoddy and deceptive tactics of their film and the ID movement as a whole, the very outcome they were hoping to avoid. How could this have turned out any better?

However, at least one non-creationist thinks this is somehow a disaster for us. Anyone care to guess who?

As long as Dawkins and PZ continue to be the representative voices from the pro-science side in this debate, it is really bad for those of us who care about promoting public trust in science and science education. Dawkins and PZ need to lay low as Expelled hits theaters. Let others play the role of communicator, most importantly the National Center for Science Education, AAAS, the National Academies or scientists such as Francis Ayala or Ken Miller. When called up by reporters or asked to comment, Dawkins and PZ should refer journalists to these organizations and individuals.

If Dawkins and PZ really care about countering the message of The Expelled camp, they need to play the role of Samantha Power, Geraldine Ferraro and so many other political operatives who through misstatements and polarizing rhetoric have ended up being liabilities to the causes and campaigns that they support. Lay low and let others do the talking.

The above piece of condescending concern trolling is courtesy of Matt Nisbet, the "framing" proponent who's only ever offered one piece of advice: namely, telling atheists to shut up and not voice their views or criticize religion. He's done this before, but this latest statement is by far the most arrogant and obnoxious one he's offered.

Nisbet's attitude seems to be that religious believers are overwhelmingly powerful, their opinions cannot be changed, and thus we must genuflect to them or else. His above post is of a piece with a long line of writings he's produced urging atheists to go back into the closet and hide - a ridiculous piece of advice which, I'm happy to say, has been treated with the contempt it deserves.

Nisbet's piece says bluntly, "It's Time To Let Others Be the Spokespeople for Science", with a prominent photo of P.Z Myers and Richard Dawkins. This claim displays a serious misunderstanding of what is going on here. Nisbet seems to assume that this position is some kind of mantle that can be passed from person to person. What he hasn't grasped is that, to whatever extent Myers and Dawkins are viewed as influential scientists whose opinions are worth listening to, they earned that authority by their own effort. They are doing just what they've always done - writing, speaking, publishing their opinions. Their following was not bestowed upon them from on high; they created it for themselves by presenting persuasive arguments that won people over. In other words, they're winning the battle of ideas, and Nisbet is not. His ridiculous call for them to shut up and hand that authority over to him is really just a plea for him to be handed the acclaim that he's failed to achieve by his own effort. The similarities with creationists are instructive.

Nisbet's post also displays what I call "the myth of the silenced middle": the notion that there's some reasonable, moderate center that's being drowned out by those on both extremes. The truth of the matter is that no one is being prevented from speaking their minds exactly as they wish. If Nisbet can't hear this mythical centrist majority, perhaps it's because they're not speaking out - and I agree that they're not, which is precisely why we radical, uncompromising atheists have arisen in the first place. We're tired of the fundamentalists shoving government and the media around without anyone standing up to them forcefully or effectively. We believe people's minds can be changed, and we intend to do just that. The vested interests of religion have not silenced us. I can assure Matt Nisbet that his comparatively feeble efforts are not going to succeed either.

UPDATE: Further thoughts.

Anointing the Sick

The New Testament's Book of James gives some very unusual instructions on how to treat illness:

"Is any sick among you? let him call for the elders of the church; and let them pray over him, anointing him with oil in the name of the Lord: And the prayer of faith shall save the sick, and the Lord shall raise him up; and if he have committed sins, they shall be forgiven him."

—James 5:14-15

In eras when human knowledge was far less advanced, it's not surprising that people would turn to superstitious practices such as prayer and anointing with oil in an attempt to cure illness. What's far more surprising is how many people still believe in these practices today, despite our far more advanced knowledge of scientific medicine, as well as ample evidence that faith healing does not work.

The Greek Orthodox Church, for example, makes anointing a regular practice, and claims that it offers physical healing:

At the conclusion of the service of the Sacrament, the body is anointed with oil, and the grace of God, which heals infirmities of soul and body, is called down upon each person.

...The Sacrament of the Unction of the sick is the Church's specific prayer for healing. If the faith of the believers is strong enough, and if it is the will of God, there is every reason to believe that the Lord can heal those who are diseased.

The Assemblies of God says the same thing:

In the Assemblies of God we believe neither the laying on of hands nor anointing with oil is indispensable for healing, for often in Scripture healing takes place without either. But at times the touch of a praying person and the application of oil are an encouragement to faith, and such a practice is enjoined by Scripture (James 5:14-16).

And, as Jeffrey Shallit reports, Prof. Clifford Blake of the University of Waterloo is an unabashed believer in faith healing through anointing and other, equally mystical methods:

Some people believe healing was only in the time of the Bible. But he knows it is happening now. When he began to use healing oil, he got more consistent results.

Granted, there are also Christians who believe the anointing is merely symbolic. And the reason they believe that should be obvious: because it is abundantly obvious, to those who know how to think critically, that anointing people with oil is not an effective method of curing illness. If there was any evidence that this was an efficacious treatment, we can be sure it would be universally employed in every Christian church, and would not be explained away as symbolic. But as scientific medicine has progressed and our ability to work real cures has increased, superstitious practices like this have become increasingly superfluous and have gradually faded away (although, as shown, there are still plenty of holdouts).

Certainly, the Bible's description of this does not seem like mere symbolism: it says clearly that "the prayer of faith" will save the sick, and in conjunction with the oil, "the Lord shall raise him up" (the Greek word, egeiro, means "to cause to rise", i.e., from a seat or a bed). My question to modern believers who view this passage symbolically is, if you know this doesn't work, how do you know that - and do you apply that same standard to the rest of the Bible? And to those who still use faith healing and dabs of magical oil, in an age of genetic manipulation, transplant surgery and antibiotics, my question is: Do you really believe that?

Other posts in this series:

• Do You Really Believe That?

Some news from earlier this year you might have missed: James Randi is officially ending his million-dollar challenge to those who claim they have psychic or supernatural powers. The challenge will be offered for two more years, and assuming no one succeeds and claims the money, will be terminated in March 2010.

It's not hard to see why Randi would do this. After ten years without a single successful applicant, I think he's made his point. Unsurprisingly, the best-known, most prominent psychic pretenders (Sylvia Browne, John Edward, etc.) have refused to even come near the challenge. The people who do apply are usually either recalcitrant and uncooperative or obviously mentally disturbed, in either case forcing Randi's staff to spend inordinate amounts of time and effort trying to get them to commit to a clear, testable claim. Here are some typical applications from the JREF's blog:

There are alternate versions of myself in different types of highly evolved states that work interchangeably to form the time process in its phasic reflective capacitations of experiential transience.

I want to show the matrix. To prove solutions and cures are withheld. Prove manipulations of sinister intent exist.

This money can be more effectively used to promote the causes of scientific inquiry and skepticism, rather than being held in trust while its caretakers try to sort through this river of nonsense. If there were any prospect that high-profile psychic claimants would agree to be tested, then I would encourage the challenge to continue, since debunking their claims in a major public forum could attract attention and interest that would greatly advance the skeptics' cause. But of course, these famous psychic pretenders know full well that this would be the outcome, and so they steadfastly avoid Randi's challenge. From their perspective, sad to say, it's a rational decision: why risk near-certain exposure and embarrassment by going up against a canny skeptic, when they can make comparable sums by safely exploiting the credulous and the gullible?

Interestingly, Randi's challenge is not the only one of its kind. The Skeptic's Dictionary lists numerous similar challenges offered by skeptical groups around the world. So, to handle the inevitable flood of flimflam artists who will step forward just after the challenge ends and announce that they could have won it, I advise pointing them to one of these challenges instead. A person who could win one or several of them would have an excellent claim for having their powers scientifically validated. Randi has also said, I believe, that he'd consider temporarily resurrecting the challenge if a famous psychic wanted to apply - so we can rest assured that woo-woo advocates will not be able to wriggle away from those pesky requests for proof, either now or in the years to come.

Human beings, like all other species on this planet, have a history. We came into existence through a process of slow, grinding trial-and-error, occurring over geological time via the sieve of differential survival. And like all species, our bodies and our genes reflect and bear witness to that history. Far from being perfect, one-time creations, we still bear the scars of the evolutionary process that made us.

This post will discuss some of the lines of evidence which hint at humanity's past. I won't repeat that well-known example of an evolutionary vestige, the human appendix. Instead, I'm going to focus on a few other examples that aren't as widely discussed.

• Toes. It's only because we're used to having toes that we don't usually consider how strange they are. Why do our feet have these stubby, non-functional digits on the ends? They can't grip nearly as well as fingers, and we don't need them to balance or to walk. (Why not just have a fused front of the foot?) By contrast, anyone who observes other primate species can see that they have, not two hands and two feet, but four hands, all of which are good for grasping. As human beings gained the ability to stand and walk upright, our feet lost their grasping function, but the digits themselves, though now shrunken and largely useless, remain.

• Lanugo. This little-known developmental phenomenon is an important clue to our mammalian past. Lanugo is a coat of fine, downy hair that fetuses grow while in the womb, covering the entire body except for the soles of the feet and the palms of the hands. Typically, lanugo is shed by the seventh or eighth month of pregnancy, although premature infants may retain it for several weeks after birth. The question is why we grow it at all, and the theory of evolution can easily explain this as a vestigial characteristic retained from our furry ancestors.

• Goosebumps. Fitting neatly together with lanugo is the vestigial human trait called the pilomotor reflex. When a person is cold or frightened, tiny muscles at the base of each hair contract, causing body hair to stand on end. In animals with thicker fur, this is a useful reflex: erect hairs trap air to create a layer of insulation, and they also make the animal appear larger and more intimidating. In humans, however, it is pointless. Like lanugo, goosebumps are a giveaway clue indicating that relatively hairless human beings are descended from furry progenitors.

• Hiccups. Yes, hiccups are a sign of humanity's evolutionary past. In fact, unlike goosebumps or lanugo, which merely point to our shared history with hairier mammals, hiccups point all the way back to the time when humanity's ancestors were amphibians. According to this article by Neil Shubin (HT: The Panda's Thumb), the hiccup reflex is controlled by an area of the brain that we share with tadpoles. The hiccup consists of a sharp inhalation followed by a closing of the glottis (the valve at the top of the windpipe). In tadpoles, which have this same reflex, the inhalation draws water into the mouth, where the gills can process the oxygen it contains, but closes the glottis so the water does not enter the lungs. For tadpoles, it's a vital breathing reflex; in humans, it's a hiccup. And the same measures that often arrest hiccups in human beings (inhaling carbon dioxide, stretching the chest wall by taking a deep breath) also stop the gill-breathing reflex in tadpoles.

• The true human tail. One of the most shocking - for creationists, anyway - human atavisms is the true human tail. On rare occasions, human infants are born with short, non-prehensile, but undeniably real tails, up to several inches in length and containing nerves, blood vessels, muscle fibers, and sometimes even extra vertebrae. They can move through voluntary muscle contraction.

In fact, all human embryos grow tails while in the womb, and normally they are reabsorbed before birth. The true human tail is the result when this does not happen. Usually they are surgically removed, although they are benign. For an evolutionary scientist, the reason why we grow them is obvious: we are descended from an ancestor species which had them. For creationists, who claim that human beings were created complete and separate as we currently are, it must be difficult to explain why we have so many vestigial structures that link us to other species of mammals.

• The fused chromosome 2. It's long been known that human beings have 23 pairs of chromosomes, while the other great apes such as gorillas and chimpanzees have 24. It is all but impossible that the lineage that led to humans could have completely lost all this genetic material and still produced a viable organism. Where, then, did the extra chromosomes go?

Chromosomes are tipped with distinctive segments of DNA called telomeres and have another special segment called a centromere in the middle. Lo and behold, human chromosome 2 has a telomere on one end, then an inactivated centromere, then a segment of telomeres in the middle, then another centromere, then a final telomere - the structure we would expect to find if two chromosomes had fused into one. When we compare this chromosome to the two appropriate ape chromosomes, we find a compelling match, indicating that this chromosomal fusion occurred at some point after the human lineage split from our ape relatives.

• The vitamin C pseudogene. Unlike most mammals, human beings can't synthesize their own vitamin C; we must ingest it as part of our diet, or else we get the disease of scurvy. Under the hypothesis of special creation, humans were created this way from the beginning, so we wouldn't expect evidence that we once had this ability but have since lost it. However, according to evolution, we are descended from other mammals, and since most mammals can make their own vitamin C, we'd expect that human ancestors did have this ability at some point as well. If this is so, our genes may preserve evidence of it.

Sure enough, human beings have a version of the vitamin C synthesis gene, but ours is "broken", disabled by mutations. Our primate relatives, who also lack this ability, also have broken versions of the gene. Just as evolutionary theory would predict, the same disabling mutations that exist in the human gene can be found in the genes of chimpanzees, orangutans, and macaques - compelling evidence that we are all descended from a primate common ancestor who incurred this mutation at some point in the past. (It's likely that this mutation wasn't selected against because all primate diets are rich in fruit, providing abundant vitamin C.)

Taken together, the scars of evolution provide abundant evidence of humanity's history. Like all species on this planet, we are not unique special creations. We are one end result of a long process of mutation sieved through selection, a countless series of adaptive compromises and tradeoffs. Our very bodies testify to the natural forces that have shaped us through the vast expanses of time.