Broca's Brain: The Romance of Science

by Carl Sagan

  IN GREECE of the second century A.D., during the reign of the Roman Emperor Marcus Aurelius, there lived a master con man named Alexander of Abonutichus. Handsome, clever and totally unscrupulous, in the words of one of his contemporaries, he “went about living on occult pretensions.” In his most famous imposture, “he rushed into the marketplace, naked except for a gold-spangled loincloth; with nothing but this and his scimitar, and shaking his long, loose hair, like fanatics who collect money in the name of Cybele, he climbed onto a lofty altar and delivered a harangue” predicting the advent of a new and oracular god. Alexander then raced to the construction site of a temple, the crowd streaming after him, and discovered-where he had previously buried it-a goose egg in which he had sealed up a baby snake. Opening the egg, he announced the snakelet as the prophesied god. Alexander retired to his house for a few days, and then admitted the breathless crowds, who observed his body now entwined with a large serpent: the snake had grown impressively in the interim.

  The serpent was, in fact, of a large and conveniently docile variety, procured for this purpose earlier in Macedonia, and outfitted with a linen head of somewhat human countenance. The room was dimly lit. Because of the press of the crowd, no visitor could stay for very long or inspect the serpent very carefully. The opinion of the multitude was that the seer had indeed delivered a god.

  Alexander then pronounced the god ready to answer written questions delivered in sealed envelopes. When alone, he would lift off or duplicate the seal, read the message, remake the envelope and attach a response. People flocked from all over the Empire to witness this marvel, an oracular serpent with the head of a man. In those cases where the oracle later proved not just ambiguous but grossly wrong, Alexander had a simple solution: he altered his record of the response he had given. And if the question of a rich man or woman revealed some weakness or guilty secret, Alexander did not scruple at extortion. The result of all this imposture was an income equivalent today to several hundred thousand dollars per year and fame rivaled by few men of his time.

  We may smile at Alexander the Oracle-Monger. Of course we all would like to foretell the future and make contact with the gods. But we would not nowadays be taken in by such a fraud. Or would we? M. Lamar Keene spent thirteen years as a spiritualist medium. He was pastor of the New Age Assembly Church in Tampa, a trustee of the Universal Spiritualist Association, and for many years a leading figure in the mainstream of the American spiritualist movement. He is also a self-confessed fraud who believes, from first-hand knowledge, that virtually all spirit readings, séances and mediumistic messages from the dead are conscious deceptions, contrived to exploit the grief and longing we feel for deceased friends and relatives. Keene, like Alexander, would answer questions given to him in sealed envelopes-in this case not in private, but on the pulpit. He viewed the contents with a concealed bright lamp or by smearing lighter fluid, either of which can render the envelope momentarily transparent. He would find lost objects, present people with astounding revelations about their private lives which “no one could know,” commune with the spirits and materialize ectoplasm in the darkness of the séance-all based on the simplest tricks, an unswerving self-confidence, and most of all, on the monumental credulity, the utter lack of skepticism he found in his parishioners and clients. Keene believes, as did Harry Houdini, that not only is such fraud rampant among the spiritualists, but also that they are highly organized to exchange data on potential clients, in order to make the revelations of the séance more astonishing. Like the viewing of Alexander’s serpent, the séances all take place in darkened rooms-because the deception would be too easily penetrated in the light. In his peak-earning years, Keene earned about as much, in equivalent purchasing power, as Alexander of Abonutichus.

  From Alexander’s time to our own-indeed, probably for as long as human beings have inhabited this planet-people have discovered they could make money by pretending to arcane or occult knowledge. A charming and enlightening account of some of these bamboozles can be found in a remarkable book published in 1852 in London, Extraordinary Popular Delusions and the Madness of Crowds, by Charles Mackay. Bernard Baruch claimed that the book saved him millions of dollars-presumably by alerting him to which idiot schemes he should not invest his money in. Mackay’s treatment ranges from alchemy, prophecy and faith healing, to haunted houses, the Crusades, and the “influence of politics and religion on the hair and beard.” The value of the book, like the account of Alexander the Oracle-Monger, lies in the remoteness of the frauds and delusions described. Many of the impostures do not have a contemporary ring and only weakly engage our passions: it becomes clear how people in other times were deceived. But after reading many such cases, we begin to wonder what the comparable contemporary versions are. People’s feelings are as strong as they always were, and skepticism is probably as unfashionable today as in any other age. Accordingly, there ought to be bamboozles galore in contemporary society. And there are.

  In Alexander’s time, as in Mackay’s, religion was the source of most accepted insights and prevailing world views. Those intent on duping the public often did so in religious language. This is, of course, still being done, as the testimony of penitent spiritualists and other late-breaking news amply attest. But in the past hundred years-whether for good or for ill-science has emerged in the popular mind as the primary means of penetrating the secrets of the universe, so we should expect many contemporary bamboozles to have a scientific ring. And they do.

  Within the last century or so, many claims have been made at the edge or border of science-assertions that excite popular interest and, in many cases, that would be of profound scientific importance if only they were true. We will shortly examine a representative sampling of them. These claims are out of the ordinary, a break from the humdrum world, and often imply something hopeful: for example, that we have vast, untapped powers, or that unseen forces are about to save us from ourselves, or that there is a still unacknowledged pattern and harmony to the universe. Well, science does sometimes make such claims-as, for example, the realization that the hereditary information we pass from generation to generation is encoded in a single long molecule called DNA, in the discovery of universal gravitation or continental drift, in the tapping of nuclear energy, in research on the origin of life or on the early history of the universe. So if some additional claim is made-for example, that it is possible to float in the air unaided, by a special effort of will-what is so different about that? Nothing. Except for the matter of proof. Those who claim that levitation occurs have an obligation to demonstrate their contention before skeptics, under controlled conditions. The burden of proof is on them, not on those who might be dubious. Such claims are too important to think about carelessly. Many assertions about levitation have been made in the last hundred years, but motion pictures of well-illuminated people rising unassisted fifteen feet into the air have never been taken under conditions which exclude fraud. If levitation were possible, its scientific and, more generally, its human implications would be enormous. Those who make uncritical observations or fraudulent claims lead us into error and deflect us from the major human goal of understanding how the word works. It is for this reason playing fast and loose with the truth is a very serious matter.

  ASTRAL PROJECTION

  CONSIDER WHAT is sometimes called astral projection. Under conditions of religious ecstasy or hypnagogic sleep, or sometimes under the influence of a hallucinogen, people report the distinct sensation of stepping outside the body, leaving it, floating effortlessly to some other place in the room (often near the ceiling), and only at the end of the experience remerging with the body. If such a thing can actually happen, it is certainly of great importance; it implies something about the nature of human personality and even about the possibility of “life after death.” Indeed, some people who have had near-death experiences, or who have been declared clinically dead and then revived, report similar sensations. But the fact that a sensation is reported does not mean that it
occurred as claimed. There might, for example, be a common experience or wiring defect in human neuroanatomy that under certain circumstances always leads to the same illusion of astral projection. (See Chapter 25.)

  There is a simple way to test astral projection. In your absence, have a friend place a book face up on a high and inaccessible shelf in the library. Then, if you ever have an astral projection experience, float to the book and read the title. When your body reawakens and you correctly announce what you have read, you will have provided some evidence for the physical reality of astral projection. But, of course, there must be no other way for you to know the title of the book, such as sneaking a peek when no one else is around, or being told by your friend or by someone your friend tells. To avoid the latter possibility, the experiment should be done “double blind”; that is, someone quite unknown to you who is entirely unaware of your existence must select and place the book and judge whether your answer is correct. To the best of my knowledge no demonstration of astral projection has ever been reported under such controlled circumstances with skeptics in attendance. I conclude that while astral projection is not excluded, there is little reason to believe in it. On the other hand, there is some evidence accumulated by Ian Stevenson, a University of Virginia psychiatrist, that young children in India and the Near East report in great detail a previous life in a moderately distant locale which they have never visited, while further inquiry demonstrates that a recently deceased person fits the child’s description very well. But this is not an experiment performed under controlled conditions, and it is at least possible that the child has overheard or been given information about which the investigator is unaware. Stevenson’s work is probably the most interesting of all contemporary research on “extrasensory perception.”

  SPIRIT RAPPING

  IN UPSTATE NEW YORK in 1848 there lived two little girls, Margaret and Kate Fox, about whom marvelous stories were told. In their presence could be heard mysterious rapping noises, later understood to be coded messages from the spirit world: Ask the spirits anything-one rap signifies no, three raps signify yes. The Fox sisters became a sensation, embarked on nationwide tours organized by their elder sister, and became the focus of rapt attention from European intellectuals and literati such as Elizabeth Barrett Browning. The “manifestations” brought about by the Fox sisters are the origins of modern spiritualism, the belief that by some special effort of will a few gifted people are able to communicate with the spirits of the dead. Keene’s associates owe a substantial debt to the Fox sisters.

  Forty years after the first “manifestations,” provoked by an uneasy conscience, Margaret Fox produced a signed confession. The raps were made-in a standing position with no apparent effort or movement-by cracking the toe and ankle joints, very much like cracking knuckles. “And that is the way we began. First, as a mere trick to frighten mother, and then, when so many people came to see us children, we were ourselves frightened, and for self-preservation forced to keep it up. No one suspected us of any trick because we were such young children. We were led on by my sister purposely and by mother unintentionally.” The eldest sister, who organized their tours, seems to have been fully conscious of the fraud. Her motive was money.

  The most instructive aspect of the Fox case is not that so many people were bamboozled; but rather that after the hoax was confessed, after Margaret Fox made a public demonstration, on the stage of a New York theater, of her “preternatural big toe,” many who had been taken in still refused to acknowledge the fraud. They pretended that Margaret had been coerced into the confession by some rationalist Inquisition. People are rarely grateful for a demonstration of their credulity.

  THE CARDIFF GIANT

  IN 1869 THE FIGURE of a larger-than-life stone man was unearthed by a farmer “while digging a well” near the village of Cardiff in western New York. Clergymen and scientists alike asserted that it was a fossilized human being from ages past, perhaps a confirmation of the Biblical account: “There were giants in those days.” Many commented on the detail of the figure, seemingly far finer than a mere artisan could have carved from stone. Why, there were even networks of tiny blue veins. But others were less impressed, including Andrew Dickson White, the first president of Cornell University, who declared it to be a pious fraud, and execrable sculpture to boot. A meticulous examination then revealed it to be of very recent origin, whereupon it emerged that the Cardiff Giant was merely a statue, a hoax engineered by George Hull of Binghamton, who described himself as “tobacconist, inventor, alchemist, atheist,” a busy man. The “blue veins” were a natural pattern in the sculpted rock. The object of the deception was to fleece tourists.

  But this uncomfortable revelation did not faze the American entrepreneur P. T. Barnum, who offered $60,000 for a three-month lease on the Cardiff Giant. When Barnum failed to secure it for traveling exhibition (the owners were making too much money to give it up), he simply had a copy made and exhibited it, to the awe of his customers and the enrichment of his pocketbook. The Cardiff Giant that most Americans have seen is this copy. Barnum exhibited a fake fake. The original is today languishing at the Farmer’s Museum in Cooperstown, New York. Both Barnum and H. L. Mencken are said to have made the depressing observation that no one ever lost money by underestimating the intelligence of the American public. The remark has worldwide application. But the lack is not in intelligence, which is in plentiful supply; rather, the scarce commodity is systematic training in critical thinking.

  CLEVER HANS, THE MATHEMATICAL HORSE

  IN THE EARLY YEARS of the twentieth century there was a horse in Germany who could read, do mathematics and exhibit a deep knowledge of world political affairs. Or so it seemed. The horse was called Clever Hans. He was owned by Wilhelm von Osten, an elderly Berliner whose character was such, everyone said, that fraud was out of the question. Delegations of distinguished scientists viewed the equine marvel and pronounced it genuine. Hans would reply to mathematical problems put to him with coded taps of his foreleg, and would answer nonmathematical questions by nodding his head up and down or shaking it side to side in the conventional Western way. For example, someone would say, “Hans, how much is twice the square root of nine, less one?” After a moment’s pause Hans would dutifully raise his right foreleg and tap five times. Was Moscow the capital of Russia? Head shake. How about St. Petersburg? Nod.

  The Prussian Academy of Sciences sent a commission, headed by Oskar Pfungst, to take a closer look; Osten, who believed fervently in Hans’s powers, welcomed the inquiry. Pfungst noticed a number of interesting regularities. Sometimes, the more difficult the question, the longer it took Hans to answer; or when Osten did not know the answer, Hans exhibited a comparable ignorance; or when Osten was out of the room, or when the horse was blindfolded, no correct answers were forthcoming. But other times Hans would get the right answer in a strange place, surrounded by skeptics, with Osten not only out of the room, but out of town. The solution eventually became clear. When a mathematical question was put to Hans, Osten would become slightly tense, for fear Hans would make too few taps. When Hans, however, reached the correct number of taps, Osten unconsciously and imperceptibly nodded or relaxed-imperceptibly to virtually all human observers, but not to Hans, who was rewarded with a sugar cube for correct answers. Even teams of skeptics would watch Hans’s foot as soon as the question was put and make gestural or postural responses when the horse reached the right answer. Hans was totally ignorant of mathematics, but very sensitive to unconscious nonverbal cues. Similar signs were unknowingly transmitted to the horse when verbal questions were posed. Clever Hans was aptly named; he was a horse who had conditioned one human being and discovered that other human beings he had never before met would provide him the needed cues. But despite the unambiguous nature of Pfungst’s evidence, similar stories of counting, reading and politically sage horses, pigs and geese have continued to plague the gullible of many nations. [2]

  PRECOGNITIVE DREAMS

  ONE OF THE MOST s
triking apparent instances of extrasensory perception is the precognitive experience, when a person has a compelling perception of an imminent disaster, the death of a loved one, or a communication from a long-lost friend, and the predicted event then transpires. Many who have had such experiences report that the emotional intensity of the precognition and its subsequent verification provide an overpowering sense of contact with another realm of reality. I have had such an experience myself. Many years ago I awoke in the dead of night in a cold sweat, with the certain knowledge that a close relative had suddenly died. I was so gripped with the haunting intensity of the experience that I was afraid to place a long-distance phone call, for fear that the relative would trip over the telephone cord (or something) and make the experience a self-fulfilling prophecy. In fact, the relative is alive and well, and whatever psychological roots the experience may have, it was not a reflection of an imminent event in the real world.

  However, suppose the relative had in fact died that night. You would have had a difficult time convincing me that it was merely coincidence. But it is easy to calculate that if each American has such a premonitory experience a few times in his lifetime, the actuarial statistics alone will produce a few apparent precognitive events somewhere in America each year. We can calculate that this must occur fairly frequently, but to the rare person who dreams of disaster, followed rapidly by its realization, it is uncanny and awesome. Such a coincidence must happen to someone every few months. But those who experience a correct precognition understandably resist its explanation by coincidence.

  After my experience I did not write a letter to an institute of parapsychology relating a compelling predictive dream which was not borne out by reality. That is not a memorable letter. But had the death I dreamt actually occurred, such a letter would have been marked down as evidence for precognition. The hits are recorded, the misses are not. Thus human nature unconsciously conspires to produce a biased reporting of the frequency of such events.