It wasn't immediately obvious to Walter Semkiw that he was the reincarnation of John Adams. Adams was a lawyer and rabble-rouser who helped overthrow a government; Semkiw is a doctor who has never so much as challenged a parking ticket. The second president was balding and wore a powdered wig; Semkiw has a full head of hair. But in 1984, a psychic told the then medical resident and psychiatrist-in-training that he is the reincarnation of a major figure of the Revolution, possibly Adams. Once Semkiw got over his skepticism—as a student of the human mind, he was of course familiar with "how people get misled and believe something that might not be true," he recalls—he wasn't going to let superficial dissimilarities dissuade him so easily. As he researched Adams's life, Semkiw began finding many tantalizing details. For instance, Adams described his handwriting as "tight-fisted and concise"—"just like mine," Semkiw realized. He also saw an echo of himself in Adams's dedication to the cause of independence from England. "I can be very passionate," Semkiw says. The details accumulated and, after much deliberation, Semkiw went with his scientific side, dismissing the reincarnation idea.
But one day in 1995, when Semkiw was the medical director for Unocal 76, the oil company, he heard a voice in his head intoning, "Study the life of Adams!" Now he found details much more telling than those silly coincidences he had learned a dozen years earlier. He looked quite a bit like the second president, Semkiw realized. Adams's description of parishioners in church pews as resembling rows of cabbages was "something I would have said," Semkiw realized. "We are both very visual." And surely it was telling that Unocal's slogan was "the spirit of '76." It was all so persuasive, thought Semkiw, who is now a doctor at the Kaiser Permanente Medical Group in California, that as a man of science and reason whose work requires him to critically evaluate empirical evidence, he had to accept that he was Adams reincarnated.
Perhaps you don't believe that Semkiw is the reincarnation of John Adams. Or that playwright August Wilson is the reincarnation of Shakespeare, or George W. Bush the reincarnation of Daniel Morgan, a colonel in the American Revolution who was known for his "awkward speech" and "coarse manners," as Semkiw chronicles on his Web site johnadams.net. But if you don't believe in reincarnation, then the odds are that you have at least felt a ghostly presence behind you in an "empty" house. Or that you have heard loved ones speak to you after they passed away. Or that you have a lucky shirt. Or that you can tell when a certain person is about to text you, or when someone unseen is looking at you. For if you have never had a paranormal experience such as these, and believe in none of the things that science says do not exist except as tricks played on the gullible or—as neuroscientists are now beginning to see—by the normal workings of the mind carried to an extreme, well, then you are in a lonely minority. According to periodic surveys by Gallup and other pollsters, fully 90 percent of Americans say they have experienced such things or believe they exist.
If you take the word "normal" as characteristic of the norm or majority, then it is the superstitious and those who believe in ESP, ghosts and psychic phenomena who are normal. Most scientists and skeptics roll their eyes at such sleight of word, asserting that belief in anything for which there is no empirical evidence is a sign of mental pathology and not normalcy. But a growing number of researchers, in fields such as evolutionary psychology and neurobiology, are taking such beliefs seriously in one important sense: as a window into the workings of the human mind. The studies are an outgrowth of research on religious faith, a (nearly) human universal, and are turning out to be useful for explaining fringe beliefs, too. The emerging consensus is that belief in the supernatural seems to arise from the same mental processes that underlie everyday reasoning and perception. But while the belief in ghosts, past lives, the ability of the mind to move matter and the like originate in normal mental processes, those processes become hijacked and exaggerated, so that the result is, well, Walter Semkiw.
Raised as a Roman Catholic, Semkiw is driven by a what-if optimism. If only people could accept reincarnation, he believes, Iraq's Sunnis and Shiites might stop fighting (since they might be killing someone who was once one of them). He is dismissive of the idea that reincarnation has not been empirically proved. That was the status of everything science has since proved, be it the ability of atoms to vibrate in synchrony (the basis of the laser) or of mold to cure once-lethal infections (penicillin). Dedicated to the empirical method, Semkiw believes the world is on the brink of "a science of spirituality," he says. "I don't know how you can't believe in reincarnation. All it takes is an open mind."
On that, he is in agreement with researchers who study the processes of mind and brain that underlie belief. As scientists began studying belief in the paranormal, it quickly became clear that belief requires an open mind—one not bound by the evidence of the senses, but in which emotions such as hope and despair can trump that evidence. Consider the Tichborne affair. In 1854, Sir Roger Tichborne, age 25, was reported lost at sea off the coast of Brazil. His inconsolable mother refused to accept that her son was dead. Twelve years later a man from Wagga Wagga, in New South Wales, Australia, got in touch with her. He claimed to be Sir Roger, so Lady Tichborne immediately sent him money to sail to England. When the claimant arrived, he turned out to be grossly obese, E.J. Wagner recounts in her 2006 book "The Science of Sherlock Holmes." Sir Roger had been very thin. Sir Roger had had tattoos on his arm. The claimant had none. He did, however, have a birthmark on his torso; Sir Roger had not. Although Sir Roger's eyes had been blue, the claimant's were brown. Lady Tichborne nevertheless joyfully proclaimed the claimant her son and granted him £1,000 per annum. Lawsuits eventually established that the claimant was an impostor.
Letting hope run roughshod over the evidence of your eyes, as Lady Tichborne did, is surprisingly easy to do: the idea that the brain constructs reality from the bottom up, starting with perceptions, is woefully wrong, new research shows. The reason the grieving mother did not "see" the claimant as others did is that the brain's sensory regions, including vision, are at the mercy of higher-order systems, such as those that run attention and emotions. If attention is not engaged, images that land on the retina and zip back to the visual cortex never make it to the next stop in the brain, where they would be processed and identified and examined critically. If Lady Tichborne chose not to focus too much on the claimant's appearance, she effectively blinded herself. Also, there is a constant back-and-forth between cognitive and emotion regions of the brain, neuroimaging studies have shown. That can heighten perception, as when fear sharpens hearing. But it can also override the senses. No wonder the poor woman didn't notice those missing tattoos on the man from Wagga Wagga.
The pervasiveness of belief in the supernatural and paranormal may seem odd in an age of science. But ours is also an age of anxiety, a time of economic distress and social anomie, as denizens of a mobile society are repeatedly uprooted from family and friends. Historically, such times have been marked by a surge in belief in astrology, ESP and other paranormal phenomena, spurred in part by a desperate yearning to feel a sense of control in a world spinning out of control. A study reported a few weeks ago in the journal Science found that people asked to recall a time when they felt a loss of control saw more patterns in random noise, perceived more conspiracies in stories they read and imagined illusory correlations in financial markets than people who were not reminded that events are sometimes beyond their control. "In the absence of perceived control, people become susceptible to detecting patterns in an effort to regain some sense of organization," says psychology researcher Bruce Hood of the University of Bristol, whose upcoming book "Supersense: Why We Believe in the Unbelievable" explores the mental processes behind belief in the paranormal. "No wonder those stock market traders are clutching their rabbit's feet"—or that psychics and the paranormal seem to be rivaling reality stars for TV hegemony ("Medium," "Psychic Kids," "Lost" and the new "Fringe" and "Eleventh Hour"). Just as great religious awakenings have coincided with tumultuous eras, so belief in the paranormal also becomes much more prevalent during social and political turmoil. Such events "lead the mind to look for explanations," says Michael Shermer, president of the Skeptics Society and author of the 1997 book "Why People Believe Weird Things." "The mind often takes a turn toward the supernatural and paranormal," which offer the comfort that benign beings are watching over you (angels), or that you will always be connected to a larger reality beyond the woes of this world (ghosts).
As science replaces the supernatural with the natural, explaining everything from thunder and lightning to the formation of planets, many people seek another source of mystery and wonder in the world. People can get that from belief in several paranormal phenomena, but none more so than thinking they were abducted by aliens. When Susan Clancy was a graduate student in psychology at Harvard University, she was struck by how ordinary the "abductees" she was studying seemed. They were respectable, job-holding, functioning members of society, normal except for their belief that short beings with big eyes once scooped them up and took them to a spaceship. They are men like Will, a massage therapist, who was abducted repeatedly by aliens, he told Clancy, and became so close to one that their union produced twin boys whom, sadly, he never sees. Numerous studies have found that abductees are not suffering from any known mental illness. They are unusually prone to false memories, and tend to be creative, fantasy-prone and imaginative. But so are lots of people who have never met a little green man.
Some 40 percent of Americans believe it's possible that aliens have grabbed some of us, polls show, compared with 25 percent in the 1980s. What makes abductees stand out is something so common, it's a wonder there aren't more of them: an inability to think scientifically. Clancy asked abductees if they understand that sleep paralysis, in which waking up during a dream causes the dream to leak into consciousness even while you remain immobilized, can produce the weird visions and helplessness that abductees describe. Of course, they say, but that doesn't apply to them. And do they understand that the most likely explanation of bad dreams, impotence, nosebleeds, loneliness, bruises or just waking up to find their pajamas on the floor does not involve aliens? Yes, they told her, but abduction feels like the best explanation. Larry, for instance, woke from a dream, saw shadowy figures around his bed and felt a stabbing pain in his groin. He ran through the possibilities—a biotech firm's stealing his sperm, angels, repressed memory of childhood sexual abuse—and only then settled on alien abduction as the most plausible. The scientific principle that the simplest explanation is most likely to be right is, well, alien to abductees. But again, an inability to think scientifically is exceedingly common. We are more irrational than we are rational; emotions drive voting behavior more strongly than analysis of candidates' records and positions does. The universal human need to find meaning and purpose in life is stronger and more basic than any attachment to empiricism, logic or objective reality.
Something as common as loneliness can draw us to the paranormal. In a study published in February, scientists induced feelings of loneliness in people by telling them that a personality questionnaire they filled out revealed that, by middle age, they would have few friends and be socially isolated. After this ruse, participants were more likely to say they believed in ghosts, angels, the Devil, miracles, curses and God than were participants who were told their future held many friendships, found Nicholas Epley, of the University of Chicago, and colleagues.
That we are suckers for weird beliefs reflects the fact that the brain systems that allow and even encourage them "evolved for other things," says James Griffith, a psychiatrist and neurologist at George Washington University. A bundle of neurons in the superior parietal lobe, a region toward the top and rear of the brain, for instance, distinguishes where your body ends and the material world begins. Without it, you couldn't navigate through a door frame. But other areas of the brain, including the thinking regions in the frontal lobes, sometimes send "turn off!" signals to this structure, such as when we are falling asleep or when we feel physical communion with another person (that's a euphemism for sex). During intense prayer or meditation, brain-imaging studies show, the structure is also especially quiet. Unable to find the dividing line between self and world, the brain adapts by experiencing a sense of holism and connectedness. You feel a part of something larger than yourself. This ability to shut off the sense of where you end and the world begins, then, may promote other beliefs that bring a sense of connection, even if they involve alien kidnappers.
Other normal brain functions can be hijacked for spooky purposes, too. Neither the eyes nor the ears can take in every aspect of an object. The brain, therefore, fills in the blanks. Consider the optical illusion known as the Kanizsa triangle, in which three black Pac-Man shapes sit at what could be the corners of a triangle, their open mouths pointed inward. Almost everyone "sees" three white lines forming that triangle, but there are in fact no lines. What does the "seeing" is not the eyes but the brain, which habitually takes messy, incomplete input and turns it into a meaningful, complete picture. This drive to see even what is not objectively there is easily hijacked. "Perceptually, the world is chronically ambiguous and requires an interpretation," says Stewart Guthrie, professor emeritus of anthropology at Fordham University and author of "Faces in the Clouds." And suddenly you see Satan in the smoke from the World Trade Center. "We see the Virgin Mary in a potato chip or Jesus on an underpass wall because we're using our existing cognitive structures to make sense of an ambiguous or amorphous stimuli," says psychologist Mark Reinecke, professor of psychiatry and behavioral sciences at Northwestern University.
Scientists mean "see" literally. Brain imaging shows that the regions that become active when people imagine seeing or hearing something are identical to those that become active when they really do see or hear something in the outside world. This holds true for schizophrenics (their visual cortex becomes active when they hallucinate people, and their auditory cortex when they hear voices, in ways that are indistinguishable from when they perceive real people and voices) and for healthy people engaging in mental imagery (think of a pink elephant). It is not too far a step for mentally healthy people to see or hear what they are thinking intensely about. Christina Puchalski, director of the George Washington Institute for Spirituality and Health, felt her dead mother's presence "with me in a very deep and profound way, emanating from a certain direction," she says. "Maybe if you're thinking very strongly about that person, your mind is creating the sense that he is there."
A more common experience is to see patterns in coincidences, something that also represents a hijacking of normal and useful brain function. You think about the girl at the party last Saturday and—bam!—she calls you. You think about the girl who chatted you up in class—and never hear from her. Guess which experience you remember? Thanks to the psychological glitch called confirmatory bias, the mind better recalls events and experiences that validate what we believe than those that refute those beliefs.
But why? Why do we remember the times we thought of someone just before she texted us and forget all the times we had no such premonition? When the mind was evolving, failing to make an association (snakes with rattles are to be avoided) could get you killed, while making a false association (dancing will make it rain) mostly just wasted time, Michael Shermer points out. "We are left with a legacy of false positives," he says. "Hallucinations become ghosts or aliens; knocking noises in an empty house indicate spirits and poltergeists; shadows and lights in a tree become the Virgin Mary."
The brain also evolved to recoil from danger, and the most frequent sources of danger back in the Stone Age were not guns and cars but saber-toothed tigers and other living things. As a result, we are programmed to impute vitality to even inanimate threats, as Bristol's Hood has demonstrated. When he gives a speech about irrational beliefs, he holds up an old cardigan and asks who would be willing to wear it in exchange for about $40. Usually, every hand in the audience shoots up. But when Hood adds that the sweater was once worn by a notorious murderer, almost every hand disappears. "People view evil as something physical, even tangible, and able to infect the sweater" as easily as lice, Hood says. "The idea of spirits and souls appearing in this world becomes more plausible if we believe in general that the nonphysical can transfer over to the physical world. From there it's only a small step to believing that a thunk in an empty house is a footstep."
There is a clear survival advantage to imputing aliveness and asking questions later. That's why, during human evolution, our ancestors developed what is called a hypersensitive agency-detection device, says Benson Saler, professor emeritus of anthropology at Brandeis University. This is an acute sensitivity to the presence of living beings, something we default to when what we perceive could be alive or inanimate. "Whether it's a rock formation or a hungry bear, it's better to assume it's a hungry bear," says Saler. "If you suppose it's a rock formation, and it turns out to be a hungry bear, you're not in business much longer." Defaulting to the "it's alive!" assumption was "of such considerable value that evolution provided us with greater sensitivity to the presence of living agents than we needed," says Saler. "We respond to the slightest hint or indication of agency by assuming there are living things present. Developing ideas about ghosts and spirits is simply a derivative of this hypersensitivity to the possibility" that a living being is present, and too bad if it also produces the occasional (or even frequent) false positives.
The belief that minds are not bound to bodies, and therefore that ghosts and other spirits exist here in the physical world, reflects a deep dualism in the human psyche. No matter how many times neuroscientists assert that the mind has no existence independent of the brain, "we still think of our essence as mental, and of our mind as being independent of body," says Fordham's Guthrie. "Once you've signed on to that, existence after death is really quite natural." This dualism shows up in children as young as 2, says psychologist Paul Bloom of Yale University: kids readily believe that people can exchange bodies, for instance, and since ghosts lack material bodies but have minds and memories, belief in dualism makes them perfectly plausible. At the even more basic level of perception, the brain is wired for faces, says Northwestern's Reinecke. "Even in the first weeks of life, infants tend to perceive angles, contours and shapes that are consistent with faces," he says. There's Mary on the potato chip again.
All of which raises a question. If the brain is wired so as to make belief in the paranormal seemingly inevitable, why are there any skeptics? And not just "any," but more assertive, activist ones. Groups such as the Committee for Skeptical Inquiry, the Skeptics Society and the James Randi Educational Foundation all work to debunk claims of the paranormal. A growing number of scientists and others now proudly wear the badge of "skeptic," just as more scholars are coming out as atheists, like Richard Dawkins did in his 2006 book "The God Delusion" and as Christopher Hitchens did in his 2007 tome "God Is Not Great." The growing numbers and assertiveness of skeptics (and public atheists) reflects the fact that they "have long felt like we belong to a beleaguered minority," says Shermer, who was once a born-again Christian. Their more aggressive attitude provides a sense of mission and community that skeptics, no less than believers, crave. It takes effort to resist the allure of belief, with its promise of fellowship, community and comfort in the face of mortality and a pointless, uncaring universe. There must be compensating rewards.
One such compensation, it is fair to say, is a feeling of intellectual superiority. It is rewarding to look at the vast hordes of believers, conclude that they are idiots and delight in the fact that you aren't. Another is that skeptics believe, or at least hope, that they can achieve at least one thing that believers seek, but without abandoning their principles. Skeptics, no less than believers, think it would be wonderful if we could speak to dead loved ones, or if we ourselves never died. But skeptics instead "seek immortality through our … lasting achievements," Shermer explains. "We, too, hope that our wishes for eternity might be fulfilled." Too bad that as they fight the good fight for rationality, their most powerful opponent is nothing less than the human brain.