Why People Believe Weird Things: Pseudoscience, Superstition, and Other Confudions of Our Time.

Michael Shermer was once a born-again Christian and, during his days as a long-distance bicyclist, a patron of a bevy of quackish diets and therapies. Now he sees himself as a knight of reason squaring off against the tireless forces of superstition and unsupported belief. As such, he founded and edits The Skeptic, a quarterly magazine dedicated to casting a critical eye on the world of strange and bizarre beliefs.

Shermer is a relative newcomer to the field of debunking zany beliefs, dominated over the past decades by such figures as former Scientific American columnist Martin Gardner and stage magician James "the Amazing" Randi. Shermer's goal throughout this set of separately written essays, mostly reprinted from The Skeptic, is to question a grab bag of more-or-less widespread beliefs that go beyond, or against, accepted scientific evidence or thinking.

His subject matter is more important than mere entertainment, though the book does provide that - giggling over other people's bizarre thought processes can be great fun. As beings of emotion as well as reason, humans are prone to fall into mental traps, many of which Shermer addresses. Even the most far-out of true believers wants to understand the world as it really is. The world Shermer presents is full of pitfalls on that path to understanding reality, and he is a solid guide through a morass of confusion. He leaves us with, if not certainty - he admits he can't quite explain all near-death experiences - at least a better grip on what constitutes justified belief.

Shermer's episodic book covers a wide range of subjects, in a wide range of manners. He takes ritual jabs at such old debunker punching bags as ESP and UFOs (through UFOlogy's newest twist, alien abduction of humans). You'll also find cogent debunkings of strange phenomena such as fire walking and psychics who can discover "unknowable" facts about strangers. The longest sections of the book take on the more-substantive issues of creationism and Holocaust revisionism.

Shermer gives point-by-point arguments against creationist and revisionist claims, using logic and evidence, not just ridicule, as weapons. He recounts debates with creationist Duane Gish before college audiences and with Holocaust revisionists Bradley Smith and David Cole on the Donahue show.

Shermer emphasizes such believers' main strategy: Never offer positive defenses of your own views - just poke holes in the "standard" stories of evolution and the Holocaust. Since science and history aren't as cut-and-dried as some laymen might think, it's easy for heretics to capitalize on science's strengths - open and hearty debate over unsettled issues - to make it seem as if biologists or historians don't know what they are talking about and are scrambling to prop up shaky stories. For example, Shermer has to admit on Donahue that the famous Holocaust story of Jews being turned into soap by Nazis is now understood not to be true. Holocaust revisionists use this sort of evolving understanding to imply that the whole Holocaust story is bunk.

While his topics vary, Shermer sets up a couple of overriding schemas through which to approach strange claims - one complicated and one brief. The complicated one is a list of "25 fallacies that lead us to believe weird things," with explanations of what's wrong with each. Shermer discusses classic logical fallacies such as the ad hominem and tu quoquo, and offers caveats such as "heresy does not equal correctness," "rumors do not equal reality," and "the unexplained is not inexplicable." The list has much wisdom for the wary thinker.

Also in Shermer's intellectual armory is a simple Humean maxim, which in paraphrase says: It's more likely that someone would lie than that miracles occur. If a story sounds too absurd or unlikely to be true like that ESP works or alien craft fly among us - never abandon lying as a probable explanation. (I enjoyed applying this maxim to an anecdote of Shermer's, in which he claims that delirious weariness during a long bicycling trip induced a fantasized alien abduction experience: Is it more believable that a debunker would have an experience providing him with a perfect debunking of a popular weird belief, or that the debunker would twist the story to suit his purposes?)

Although the book certainly offers valuable insights and pleasure, sometimes it falls short of Shermer's own standards. For instance, in a chapter on Satanic cult panics, he merely presents the believers' case and declares it obviously absurd. Well, sure, but we expect a better argument than that for our $22.95. And the book doesn't entirely live up to its title: Shermer doesn't spend much time really addressing the question of why people believe the strange things they believe.

But that choice actually makes this a better book. While the psychology of believers is an interesting topic in its own right, it is not the most important element in the skeptical debunker's strategy. To debunk, the most important thing is not to explain people's possibly twisted reasons for believing what they believe, but to challenge those beliefs with logic and evidence. After all, if logic and evidence aren't sufficient, then casting aspersions on motives isn't going to get the debunker anywhere either, except with people who believe (wrongly) that bad motives equal bad arguments.

Shermer himself seems to believe this at times, weakening his arguments. For example, his chapter on belief in racial differences in intelligence presents a reasonable critique of Robert Herrnstein and Charles Murray's The Bell Curve, based on the slippery definition of the concept of "race." But before he gets into that, he spends a few pages indulging in ad hominem assaults on the racist motives of Wycliffe Draper, the deceased founder of the Pioneer Fund, which funded some of the research the authors relied on.

Indeed, when Shermer does try to answer the "why?" question, he inadvertently provides further evidence of how difficult, and perhaps irrelevant to the debunker, the question is. He offers as the chief reason for why people believe weird things the truism that "hope springs eternal." To support this, he spends a chapter on the outre speculations of physicist Frank Tipler of Tulane University, who uses sophisticated physics to argue that in the distant future a supercomputer could essentially resurrect the dead - a hopeful thought, to say the least.

But how could Shermer miss that most of his book's weirdnesses have nothing to do with hope? The theories that Shermer explores thrust their believers into a frightening world indeed, one in which humans are snatched and experimented on by inscrutable aliens, omnipresent Satanic covens abuse and murder children, and an inferior and malevolent race has such total control over all information sources that blatant lies about recent history are accepted as gospel truth.

Clinicians have terms - delusion and paranoia among them - for what motivates those sorts of beliefs. But merely throwing around therapeutic scare words isn't enough to debunk. Again we see that answering the "why?" question can't do the skeptic's work. To thoroughly support accusations of delusion and paranoia, one must marshal evidence that what the believer asserts isn't true.

As a Humean, Shermer often likes to emphasize the inherent uncertainty in the search for knowledge. He often grapples with biblical fundamentalist thinking, countering it with an emphasis on the open-ended nature of science. In a chapter attacking the cult of personality that arose around Ayn Rand, he pinpoints the main flaw in Objectivism as the belief in reason's ability to discern absolute truths about reality and morality, which makes "the final results of inquiry become more important than the process of inquiry." His critique of Rand conflates the always small cult of personality around her with her larger audience, and thus declares a premature obituary on her philosophy: "Its absolutism was the biggest flaw in Ayn Rand's Objectivism, the unlikeliest cult in history," he writes. "The historical development and ultimate destruction of her group and philosophy is the empirical evidence that documents this assertion." (He doesn't attack every aspect of Rand's conclusions, merely her way of reaching them.)

But Shermer doesn't always follow the dictates of liberal epistemological skepticism implied in his attack on Rand. The professional debunker tends to be cocksure, often shutting off "process[es] of inquiry" because he thinks results are certain. For example, Shermer writes, "Shouldn't we know by now that the laws of science prove that ghosts cannot exist?" Maybe Shermer wouldn't have written that if he'd thought about it twice. In a similar slip, he quotes approvingly a weird paragraph from anthropologist Marvin Harris regarding witch hunts in olden times, which embodies reflexive anti-clericism more than rationality: "Did your roof leak, your cow abort, your oats wither, your wine go sour, your head ache, your baby die? It was the work of the witches. Preoccupied with the fantastic activities of these demons, the distraught, alienated, pauperized masses blamed the rampant Devil instead of the corrupt clergy and the rapacious nobility." So it was priests and princes who were making your head ache, your oats wither, and your cow abort?

Shermer exhibits the typical debunker's bland certainty that belies their stance as constant skeptics, and so maddens both opponents and some sympathizers. He lets slip lines like "Science became my belief system, and evolution my doctrine" (that's just how creationists accuse evolutionists of thinking) and "It is our job...to investigate and refute bogus claims." Not, "investigate claims to discover if they are bogus," but investigate and refute bogus claims. This may seem like a minor linguistic quibble, but it exactly describes the typical debunker's approach. They always know their conclusion going in - the phenomenon in question is a fraud - and are merely looking for supporting evidence.

Shermer's visit to an ESP testing lab exhibits this sometimes unpleasant attitude. It's the typical ESP routine, where people try to guess which of five simple shapes on a card is being displayed somewhere they can't see. By pure chance, one would expect five correct responses out of 25. Of course, sometimes people do better or worse than five correct. Shermer tries, of course, to dissuade his fellow test takers from believing that any results above chance indicate ESP by explaining bell-curve probability distributions.

One woman, weakening in her support for ESP, proffers the phenomenon of a friend calling just as she thought of calling the friend. How would Shermer explain that, she challenges. Shermer makes her realize that, as many times as that might happen, there were plenty of other times when she thought of her friend and her friend didn't call, or her friend called without being thought of.

Ah, maybe it was just selective perception, not ESP, the woman begins to think. Shermer is elated. A new convert to pure materialism! But the woman confounds poor Shermer by making the perfectly reasonable - given just the evidence at hand - deduction that sometimes ESP works, and sometimes it doesn't, for reasons we don't yet know enough to understand. Shermer, dedicated to a larger principle that ESP can't exist (based on plenty of evidence, to be sure, that's not on the table in that discussion), considers the woman's conclusion dimwitted.

That kind of uncharitable reaction, while understandable in the face of rampant, virulent credulousness, does no credit to the cause of skepticism, which should rely as rigorously as possible on evidence and reason, not holding stubbornly on to preconceptions. Still, despite his occasional flaws, Shermer makes clear that virulent credulousness is more on the march in our world than virulent skepticism, and shows that his chosen profession is a valuable one.

Brian Doherty ([e-mail]) is assistant editor of REASON.