Broca's Brain: The Romance of Science

CHAPTER 5

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.

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.”

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.

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.

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]

ONE OF THE MOST striking 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.

THESE CASES-Alexander the Oracle-Monger, Keene, astral projection, the Fox sisters, the Cardiff Giant, Clever Hans and precognitive dreams-are typical of claims made on the boundary or edge of science. An amazing assertion is made, something out of the ordinary, marvelous or awesome-or at least not tedious. It survives superficial scrutiny by lay people and, sometimes, more detailed study and more impressive endorsement by celebrities and scientists. Those who accept the validity of the assertion resist all attempts at conventional explanation. The most common correct explanations are of two sorts. One is conscious fraud, usually by those with a financial interest in the outcome, as with the Fox sisters and the Cardiff Giant. Those who accept the phenomena have been bamboozled. The other explanation often applies when the phenomena are uncommonly subtle and complex, when nature is more intricate than we have guessed, when deeper study is required for understanding; Clever Hans and many precognitive dreams fit this second explanation. Here, very often, we bamboozle ourselves.

I have chosen the foregoing cases for another reason. They are all closely involved with everyday life-human or animal behavior, evaluating the reliability of evidence, occasions for the exercise of common sense. None of these cases involve technological complexities or arcane theoretical developments. We do not need an advanced degree in physics, let us say, to have our skeptical hackles rise at the pretensions of modern spiritualists. Nevertheless, these hoaxes, impostures and misapprehensions have captivated millions. How much more dangerous and difficult to assess must be borderline claims at the edge of less familiar sciences-about cloning, say, or cosmic catastrophes or lost continents or unidentified flying objects?

I make a distinction between those who perpetrate and promote borderline belief systems and those who accept them. The latter are often taken by the novelty of the systems, and the feeling of insight and grandeur they provide. These are in fact scientific attitudes and scientific goals. It is easy to imagine extraterrestrial visitors who looked like human beings, and flew space vehicles and even airplanes like our own, and taught our ancestors civilization. This does not strain our imaginative powers overly and is sufficiently similar to familiar Western religious stories to seem comfortable. The search for Martian microbes of exotic biochemistry, or for interstellar radio messages from intelligent beings biologically very dissimilar is more difficult to grasp and not as comforting. The former view is widely purveyed and available; the latter much less so. Yet I think many of those excited by the idea of ancient astronauts are motivated by sincere scientific (and occasionally religious) feelings. There is a vast untapped popular interest in the deepest scientific questions. For many people, the shoddily thought out doctrines of borderline science are the closest approximation to comprehensible science readily available. The popularity of borderline science is a rebuke to the schools, the press and commercial television for their sparse, unimaginative and ineffective efforts at science education; and to us scientists, for doing so little to popularize our subject.

Advocates of ancient astronauts-the most notable being Erich von Däniken in his book Chariots of the Gods?-assert that there are numerous pieces of archaeological evidence that can be understood only by past contact by extraterrestrial civilizations with our ancestors. An iron pillar in India; a plaque in Palenque, Mexico; the pyramids of Egypt; the stone monoliths (all of which, according to Jacob Bronowski, resemble Benito Mussolini) on Easter Island; and the geometrical figures in Nazca, Peru, are all alleged to have been manufactured by or under the supervision of extraterrestrials. But in every case the artifacts in question have plausible and much simpler explanations. Our ancestors were no dummies. They may have lacked high technology, but they were as smart as we, and they sometimes combined dedication, intelligence and hard work to produce results that impress even us. The ancient-astronaut idea, interestingly, is popular among bureaucrats and politicians in the Soviet Union, perhaps because it preserves the old religious ideas in an acceptably modern scientific context. The most recent version of the ancient-astronaut story is the claim that the Dogon people in the Republic of Mali have an astronomical tradition concerning the star Sirius which they could only have acquired by contact with an alien civilization. This seems, in fact, to be the correct explanation, but it has nothing to do with astronauts, ancient or modern. (See Chapter 6.)

It is not surprising that pyramids have played a role in ancient-astronaut writings; ever since the Napoleonic invasions of Egypt impressed ancient Egyptian civilization on the consciousness of Europe, they have been the focus of a great deal of nonsense. Much has been written about supposed numerological information stored in the dimensions of the pyramids, especially the great pyramid of Gizeh, so that, for example, the ratio of height to width in certain units is said to be the time between Adam and Jesus in years. In one famous case a pyramidologist was observed filing a protuberance so that the observations and his speculations would be in better accord. The most recent manifestation of interest in pyramids is “pyranridology,” the contention that we and our razor blades feel better and last longer inside pyramids than we and they do inside cubes. Maybe. I find living in cubical dwellings depressing, and for most of our history human beings did not live in such quarters. But the contentions of pyramidology, under appropriately controlled conditions, have never been verified. Again, the burden of proof has not been met.

The Bermuda Triangle “mystery” has to do with unexplained disappearances of ships and airplanes in a vast region of the ocean around Bermuda. The most reasonable explanation for these disappearances (when they actually occur; many of the alleged disappearances turn out simply never to have happened) is that the vessels sank. I once objected on a television program that it seemed strange for ships and airplanes to disappear mysteriously but never trains; to which the host, Dick Cavett, replied, “I can see you’ve never waited for the Long Island Railroad.” As with the ancient-astronaut enthusiasts, the Bermuda Triangle advocates use sloppy scholarship and rhetorical questions. But they have not provided compelling evidence. They have not met the burden of proof.

Flying saucers, or UFOs, are well known to almost everyone. But seeing a strange light in the sky does not mean that we are being visited by beings from the planet Venus or a distant galaxy named Spectra. It might, for example, be an automobile headlight reflected off a high-altitude cloud, or a flight of luminescent insects, or an unconventional aircraft, or a conventional aircraft with unconventional lighting patterns, such as a high-intensity searchlight used for meteorological observations. There are also a number of cases-closer encounters with some highish index numeral-where one or two people claim to have been taken aboard an alien spaceship, prodded and probed with unconventional medical instruments, and released. But in these cases we have only the unsubstantiated testimony, no matter how heartfelt and seemingly sincere, of one or two people. To the best of my knowledge there are no instances out of the hundreds of thousands of UFO reports filed since 1947-not a single one-in which many people independently and reliably report a close encounter with what is clearly an alien spacecraft.

Not only is there an absence of good anecdotal evidence; there is no physical evidence either. Our laboratories are very sophisticated. A product of alien manufacture might readily be identified as such. Yet no one has ever turned up even a small fragment of an alien spacecraft that has passed any such physical test-much less the logbook of the starship captain. It is for these reasons that in 1977 NASA declined an invitation from the Executive Office of the President to undertake a serious investigation of UFO reports. When hoaxes and mere anecdotes are excluded, there seems to be nothing left to study.

Once I spied a bright, “hovering” UFO, and pointing it out to some friends in a restaurant, soon found myself in the midst of a throng of patrons, waitresses, cooks and proprietors milling about on the sidewalk, pointing up into the sky with fingers and forks, and making gasps of astonishment. People were somewhere between delighted and awestruck. But when I returned with a pair of binoculars which clearly showed the UFO to be an unconventional aircraft (a NASA weather airplane, as it later turned out), there was uniform disappointment. Some felt embarrassed at the public exposure of their credulity. Others were simply disappointed at the evaporation of a good story, something out of the ordinary-a visitor from another world.

In many such cases we are not unbiased observers. We have an emotional stake in the outcome-perhaps merely because the borderline belief system, if true, makes the world a more interesting place; but perhaps because there is something there that strikes more deeply into the human psyche. If astral projection actually occurs, then it is possible for some thinking and perceiving part of me to leave my body and effortlessly travel to other places-an exhilarating prospect. If spiritualism is real, then my soul will survive the death of my body-possibly a comforting thought. If there is extrasensory perception, then many of us possess latent talents that need only be tapped to make us more powerful than we are. If astrology is right, then our personalities and destinies are intimately tied to the rest of the cosmos. If elves and goblins and fairies truly exist (there is a lovely Victorian picture book showing photographs of six-inch-high undraped ladies with gossamer wings conversing with Victorian gentlemen), then the world is a more intriguing place than most adults have been led to believe. If we are now being or in historical times have been visited by representatives from advanced and benign extraterrestrial civilizations, perhaps the human predicament is not so dire as it seems; perhaps the extraterrestrials will save us from ourselves. But the fact that these propositions charm or stir us does not guarantee their truth. Their truth depends only on whether the evidence is compelling; and my own, and sometimes reluctant, judgment is that compelling evidence for these and many similar propositions simply does not (at least as yet) exist.

What is more, many of these doctrines, if false, are pernicious. In simplistic popular astrology we judge people by one of twelve character types depending on their month of birth. But if the typing is false, we do an injustice to the people we are typing. We place them in previously collected pigeonholes and do not judge them for themselves, a typing familiar in sexism and racism.

The interest in UFOs and ancient astronauts seems at least partly the result of unfulfilled religious needs. The extraterrestrials are often described as wise, powerful, benign, human in appearance, and sometimes they are attired in long white robes. They are very much like gods and angels, coming from other planets rather than from heaven, using spaceships rather than wings. There is a little pseudoscientific overlay, but the theological antecedents are clear: in many cases the supposed ancient astronauts and UFO occupants are deities, feebly disguised and modernized, but easily recognizable. Indeed, a recent British survey suggests that more people believe in extraterrestrial visitations than in God.

Classical Greece was replete with stories in which the gods came down to Earth and conversed with human beings. The Middle Ages were equally rich in apparitions of saints and Virgins. Gods, saints and Virgins were all recorded repeatedly over centuries by people of the highest apparent reliability. What has happened? Where have all the Virgins gone? What has happened to the Olympian gods? Have these beings simply abandoned us in recent and more skeptical times? Or could these early reports reflect the superstition and credulity and unreliability of witnesses? And this suggests a possible social danger from the proliferation of UFO cultism: if we believe that benign extraterrestrials will solve our problems, we may be tempted to exert less than our full measure of effort to solve them ourselves-as has occurred in millennialist religious movements many times in human history.

All the really interesting UFO cases depend on believing that one or a few witnesses were not bamboozling or bamboozled. Yet the opportunity for deception in eyewitness accounts is breathtaking: (1) When a mock robbery is staged for a law school class, few of the students can agree on the number of intruders, their clothing, weapons or comments, the sequence of events or the time the robbery took. (2) Teachers are presented with two groups of children who have, unknown to them, tested equally well on all examinations. But the teachers are informed that one group is smart and the other dumb. The subsequent grades reflect that initial and erroneous assessment, independent of the performance of the students. Predispositions bias conclusions. (3) Witnesses are shown a motion picture of an automobile accident. They are then asked a series of questions such as “Did the blue car run the stop sign?” A week later, when questioned again, a large proportion of the witnesses claim to have seen a blue car-despite the fact that no remotely blue car is in the film. There seems to be a stage, shortly after an eyewitness event, in which we verbalize what we think we have seen and then forever after lock it into our memories. We are very vulnerable in that stage, and any prevailing beliefs-in Olympian gods or Christian saints or extraterrestrial astronauts, say-can unconsciously influence our eyewitness account.

Those skeptical of many borderline belief systems are not necessarily those afraid of novelty. For example, many of my colleagues and I are deeply interested in the possibility of life, intelligent or otherwise, on other planets. But we must be careful not to foist our wishes and fears upon the cosmos. Instead, in the usual scientific tradition, our objective is to find out what the answers really are, independent of our emotional predispositions. If we are alone, that is a truth worth knowing also. No one would be more delighted than I if intelligent extraterrestrials were visiting our planet. It would make my job enormously easier. Indeed, I have spent more time than I care to think about on the UFO and ancient astronaut questions. And public interest in these matters is, I believe, at least in part, a good thing. But our openness to the dazzling possibilities presented by modern science must be tempered by some hard-nosed skepticism. Many interesting possibilities simply turn out to be wrong. An openness to new possibilities and a willingness to ask hard questions are both required to advance our knowledge. And the asking of tough questions has an ancillary benefit: political and religious life in America, especially in the last decade and a half, has been marked by an excessive public credulity, an unwillingness to ask difficult questions, which has produced a demonstrable impairment in our national health. Consumer skepticism makes quality products. This may be why governments and churches and school systems do not exhibit unseemly zeal in encouraging critical thought. They know they themselves are vulnerable.

Professional scientists generally have to make a choice in their research goals. There are some objectives that would be very important if achieved, but that promise so small a likelihood of success that no one is willing to pursue them. (For many years this was the case in the search for extraterrestrial intelligence. The situation has changed mainly because advances in radio technology now permit us to construct enormous radio telescopes with sensitive receivers to pick up any messages that might be sent our way. Never before in human history was this possible.) There are other scientific objectives that are perfectly tractable but of entirely trivial significance. Most scientists choose a middle course. As a result, very few scientists actually plunge into the murky waters of testing or challenging borderline or pseudo-scientific beliefs. The chance of finding out something really interesting-except about human nature-seems small, and the amount of time required seems large. I believe that scientists should spend more time in discussing these issues, but the fact that a given contention lacks vigorous scientific opposition in no way implies that scientists think it is reasonable.

There are many cases where the belief system is so absurd that scientists dismiss it instantly but never commit their arguments to print. I believe this is a mistake. Science, especially today, depends upon public support. Because most people have, unfortunately, a very inadequate knowledge of science and technology, intelligent decision making on scientific issues is difficult. Some pseudoscience is a profitable enterprise, and there are proponents who not only are strongly identified with the issue in question but also make large amounts of money from it. They are willing to commit major resources to defending their contentions. Some scientists seem unwilling to engage in public confrontations on borderline science issues because of the effort required and the possibility that they will be perceived to lose a public debate. But it is an excellent opportunity to show how science works at its murkier borders, and also a way to convey something of its power as well as its pleasures.

There is stodgy immobility on both sides of the borders of the scientific enterprise. Scientific aloofness and opposition to novelty are as much a problem as public gullibility. A distinguished scientist once threatened to sic then Vice President Spiro T. Agnew on me if I persisted in organizing a meeting of the American Association for the Advancement of Science in which both proponents and opponents of the extraterrestrial-spacecraft hypothesis of UFO origins would be permitted to speak. Scientists offended by the conclusions of Immanuel Velikovsky’s Worlds in Collision and irritated by Velikovsky’s total ignorance of many well-established scientific facts successfully and shamefully pressured Velikovsky’s publisher to abandon the book-which was then put out by another firm, much to its profit-and when I arranged for a second AAAS symposium to discuss Velikovsky’s ideas, I was criticized by a different leading scientist who argued that any public attention, no matter how negative, could only aid Velikovsky’s cause.

But these symposia were held, the audiences seemed to find them interesting, the proceedings were published, and now youngsters in Duluth or Fresno can find some books presenting the other side of the issue in their libraries. (See Chapter 5.) If science is presented poorly in schools and the media, perhaps some interest can be aroused by well-prepared, comprehensible public discussions at the edge of science. Astrology can be used for discussions of astronomy; alchemy for chemistry; Velikovskian catastrophism and lost continents such as Atlantis for geology; and spiritualism and Scientology for a wide range of issues in psychology and psychiatry.

There are still many people in the United States who believe that if a thing appears in print it must be true. Since so much undemonstrated speculation and rampant nonsense appears in books, a curiously distorted view of what is true emerges. I was amused to read-in the furor that followed the premature newspaper release of the contents of a book by H. R. Haldeman, a former presidential assistant and convicted felon-what the editor in chief of one of the largest publishing companies in the world had to say: “We believe a publisher has an obligation to check out the accuracy of certain controversial non-fiction works. Our procedure is to send the book out for an objective reading by an independent authority in the field.” This is by an editor whose firm has in fact published some of the most egregious pseudoscience of recent decades. But books presenting the other side of the story are now becoming available, and in the section below I have listed a few of the more prominent pseudoscientific doctrines and recent attempts at their scientific refutation. One of the contentions criticized-that plants have emotional lives and musical preferences-had a brief flurry of interest a few years ago, including weeks of conversations with vegetables in Gary Trudeau’s “Doonesbury” comic strip. As an epigraph to this chapter (on the death struggle of the snapdragon) shows, it is an old contention. Perhaps the only encouraging point is that it is being greeted more skeptically today than it was in 1926.

While many recent borderline doctrines are widely promoted, skeptical discussion and dissection of their fatal flaws are not so widely known. This table is a guide to some of these critiques.

Bermuda Triangle::The Bermuda Triangle Mystery-Solved,

Laurence Kusche, Harper & Row,1975

Spiritualism::A Magician Among the Spirits,Harry Houdini, Harper, 1924

The Psychic Mafia,M. Lamar Keene, St. Martin’s Press,

1976

Uri Geller::The Magic of Uri Geller,James Randi, Ballantine, 1975

Atlantis and other “lost continents”::Legends of the Earth: Their GeologicOrigins,Dorothy B. Vitaliano, Indiana UniversityPress, 1973 Lost Continents,L. Sprague de Camp, Ballantine,1975

UFOs::UFOs Explained,Philip Klass, Random House, 1974

UFOs: A Scientific Debate,

Carl Sagan and Thornton Page, eds.,

Norton, 1973

Ancient Astronauts::The Space Gods Revealed: A Close

Look at the Theories of Erich von Däniken,

Ronald Story, Harper & Row, 1976

The Ancient Engineers,

L. Sprague de Camp, Ballantine, 1973

Velikovsky:::Scientists Confront Velikovsky,

Worlds in Collision::Donald Goldsmith, ed., Cornell

University Press, 1977

The Emotional Lives of Plants::“Plant ‘Primary Perception,’ ”

K. A. Horowitz and others, Science,

189: 478-480 (1975)

A FEW YEARS AGO a committee of scientists, magicians and others was organized to provide some focus for skepticism on the border of science. This nonprofit organization is called “The Committee for the Scientific Investigation of Claims of the Paranormal” and is at 923 Kensington Avenue, Buffalo, N.Y. 14215. It is beginning to do some useful work, including in its publications the latest news on the confrontation between the rational and the irrational-a debate that goes back to the encounters between Alexander the Oracle-Monger and the Epicureans, who were the rationalists of his day. The committee has also made official protests to the networks and the Federal Communications Commission about television programs on pseudoscience that are particularly uncritical. An interesting debate has gone on within the committee between those who think that all doctrines that smell of pseudoscience should be combated and those who believe that each issue should be judged on its own merits, but that the burden of proof should fall squarely on those who make the proposals. I find myself very much in the latter camp. I believe that the extraordinary should certainly be pursued. But extraordinary claims require extraordinary evidence.

Scientists are, of course, human. When their passions are excited they may abandon temporarily the ideals of their discipline. But these ideals, the scientific method, have proved enormously effective. Finding out the way the world really works requires a mix of bunches, intuition and brilliant creativity; it also requires skeptical scrutiny of every step. It is the tension between creativity and skepticism that has produced the stunning and unexpected findings of science. In my opinion the claims of borderline science pall in comparison with hundreds of recent activities and discoveries in real science, including the existence of two semi-independent brains within each human skull; the reality of black holes; continental drift and collisions; chimpanzee language; massive climatic changes on Mars and Venus; the antiquity of the human species; the search for extraterrestrial life; the elegant self-copying molecular architecture that controls our heredity and evolution; and observational evidence on the origin, nature and fate of the universe as a whole.

But the success of science, both its intellectual excitement and its practical application, depend upon the self-correcting character of science. There must be a way of testing any valid idea. It must be possible to reproduce any valid experiment. The character or beliefs of the scientist are irrelevant; all that matters is whether the evidence supports his contention. Arguments from authority simply do not count; too many authorities have been mistaken too often. I would like to see these very effective scientific modes of thought communicated by the schools and the media; and it would certainly be an astonishment and delight to see them introduced into politics. Scientists have been known to change their minds completely and publicly when presented with new evidence or new arguments. I cannot recall the last time a politician displayed a similar openness and willingness to change.

Many of the belief systems at the edge or fringe of science are not subject to crisp experimentation. They are anecdotal, depending entirely on the validity of eyewitnesses who, in general, are notoriously unreliable. On the basis of past performance most such fringe systems will turn out to be invalid. But we cannot reject out of hand, any more than we can accept at face value, all such contentions. For example, the idea that large rocks can drop from the skies was considered absurd by eighteenth-century scientists; Thomas Jefferson remarked about one such account that he would rather believe that two Yankee scientists lied than that stones fell from the heavens. Nevertheless, stones do fall from the heavens. They are called meteorites, and our preconceptions have no bearing on the truth of the matter. But the truth was established only by a careful analysis of dozens of independent witnesses to a common meteorite fall, supported by a great body of physical evidence, including meteorites recovered from the eaves of houses and the furrows of plowed fields.

Prejudice means literally pre-judgment, the rejection of a contention out of hand, before examining the evidence. Prejudice is the result of powerful emotions, not of sound reasoning. If we wish to find out the truth of a matter we must approach the question with as nearly open a mind as we can, and with a deep awareness of our own limitations and predispositions. On the other hand, if after carefully and openly examining the evidence, we reject the proposition, that is not prejudice. It might be called “post-judice.” It is certainly a prerequisite for knowledge.

Critical and skeptical examination is the method used in everyday practical matters as well as in science. When buying a new or used car, we think it prudent to insist on written warranties, test drives and checks of particular parts. We are very careful about car dealers who are evasive on these points. Yet the practitioners of many borderline beliefs are offended when subjected to similarly close scrutiny. Many who claim to have extrasensory perception also claim that their abilities decline when they are carefully watched. The magician Uri Geller is happy to warp keys and cutlery in the vicinity of scientists-who, in their confrontations with nature, are used to an adversary who fights fair; but is greatly affronted at the idea of performances before an audience of skeptical magicians-who, understanding human limitations, are themselves able to perform similar effects by sleight of hand. Where skeptical observation and discussion are suppressed, the truth is hidden. The proponents of such borderline beliefs, when criticized, often point to geniuses of the past who were ridiculed. But the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown.

The best antidote for pseudoscience, I firmly believe, is science:

There is an African fresh-water fish that is blind. It generates a standing electric field, through perturbations in which it distinguishes between predators and prey and communicates in a fairly elaborate electrical language with potential mates and other fish of the same species. This involves an entire organ system and sensory capability completely unknown to pretechnological human beings.

There is a kind of arithmetic, perfectly reasonable and self-contained, in which two times one does not equal one times two.

Pigeons-one of the least prepossessing animals on Earth-are now found to have a remarkable sensitivity to magnetic-field strengths as small as one hundred thousandth that of the Earth’s magnetic dipole. Pigeons evidently use this sensory capability for navigation and sense their surroundings by their magnetic signatures: metal gutters, electrical power lines, fire escapes and the like-a sensory modality glimpsed by no human being who ever lived.

Quasars seem to be explosions of almost unimaginable violence in the hearts of galaxies which destroy millions of worlds, many of them perhaps inhabited.

In an East African volcanic ash flow 3.5 million years old there are footprints-of a being about four feet high with a purposeful stride that may be the common ancestor of apes and men. Nearby are the prints of a knuckle-walking primate corresponding to no animal yet discovered.

Each of our cells contains dozens of tiny factories called mitochondria which combine our food with molecular oxygen in order to extract energy in convenient form. Recent evidence suggests that billions of years ago the mitochondria were free organisms which have slowly evolved into a mutually dependent relation with the cell. When many-celled organisms arose, the arrangement was retained. In a very real sense, then, we are not a single organism, but an array of about ten trillion beings and not all of the same kind.

Mars has a volcano almost 80,000 feet high which was constructed about a billion years ago. An even larger volcano may exist on Venus.

Radio telescopes have detected the cosmic black-body background radiation, the distant echo of the event called the Big Bang. The fires of creation are being observed today.

I could continue such a list almost indefinitely. I believe that even a smattering of such findings in modern science and mathematics is far more compelling and exciting than most of the doctrines of pseudoscience, whose practitioners were condemned as early as the fifth century B.C. by the Ionian philosopher Heraclitus as “night-walkers, magicians, priests of Bacchus, priestesses of the wine-vat, mystery-mongers.” But science is more intricate and subtle, reveals a much richer universe, and powerfully evokes our sense of wonder. And it has the additional and important virtue-to whatever extent the word has any meaning-of being true.

CHAPTER 6

HUMANITY HAS already achieved interstellar spaceflight. With a gravitational assist from the planet Jupiter, the Pioneer 10 and 11 and the Voyager 1 and 2 spacecraft have been boosted into trajectories that will leave the solar system for the realm of the stars. They are very slow-moving spacecraft despite the fact that they are the fastest objects ever launched by our species. They will take tens of thousands of years to travel typical interstellar distances. Unless some special effort is made to redirect them, they will never enter another planetary system in all the tens of billions of years of future history of the Milky Way Galaxy. The star-to-star distances are too large. They are doomed to wander forever in the dark between the stars. But even so, these spacecraft have messages attached to them for the remote contingency that at some future time, alien beings might intercept the spacecraft and wonder about the beings who launched them on these prodigious journeys. [3]

If we are capable of such constructions at our comparatively backward technological state, might not a civilization thousands or millions of years more advanced than ours, on a planet of another star, be capable of fast and directed interstellar travel? Interstellar spaceflight is time-consuming, difficult and expensive for us, and perhaps also for other civilizations with substantially greater resources than ours. But it surely would be unwise to contend that conceptually novel approaches to the physics or engineering of interstellar spaceflight will not be discovered by us sometime in the future. It is evident that for economy, efficiency and convenience, interstellar radio transmission is much superior to interstellar spaceflight, and this is the reason that our own efforts have concentrated strongly on radio communication. But radio communication is clearly inappropriate for contact with a pretechnological society or species. No matter how clever or powerful the transmission, no such radio message would have been received or understood on Earth before the present century. And there has been life on our planet for about four billion years, human beings for several million, and civilization for perhaps ten thousand.

It is not inconceivable that there is a kind of Galactic Survey, established by cooperating civilizations on many planets throughout the Milky Way Galaxy, which keeps an eye (or some equivalent organ) on emerging planets and seeks out undiscovered worlds. But the solar system is very far from the center of the Galaxy and could well have eluded such searches. Or survey ships may come here, but only every ten million years, say-with none having arrived during historical times. However, it is also possible that a few survey teams have arrived recently enough in human history for their presence to have been noted by our ancestors, or even for human history to have been affected by the contact.

The Soviet astrophysicist I. S. Shklovskii and I discussed this possibility in our book, Intelligent Life in the Universe, in 1966. We examined a range of artifacts, legends and folklore from many cultures and concluded that not one of these cases provided even moderately convincing evidence for extraterrestrial contact. There are always more plausible alternative explanations based on known human abilities and behavior. Among the cases discussed were a number later accepted by Erich von Däniken and other uncritical writers as valid evidence for extraterrestrial contact: Sumerian legends and astronomical cylinder seals; the Biblical stories of the Slavonic Enoch and of Sodom and Gomorrah; the Tassili frescoes in North Africa; the machined metal cube allegedly found in ancient geological sediments and said to be displayed in a museum in Austria; and so on. Over the years I have continued to look as deeply as I am able into such stories and have found very few that require more than passing attention.

In the long litany of “ancient astronaut” pop archaeology, the cases of apparent interest have perfectly reasonable alternative explanations, or have been misreported, or are simple prevarications, hoaxes and distortions. This description applies to arguments about the Piri Reis map, the Easter Island monoliths, the heroic drawings on the plains of Nazca, and various artifacts from Mexico, Uzbekistan and China.

And yet, it would be so easy for an advanced extraterrestrial civilization to leave a completely unambiguous calling card of their visit. For example, many nuclear physicists believe that there is an “island of stability” of atomic nuclei, near a hypothetical superheavy atom with about 114 protons and about 184 neutrons. All chemical elements heavier than uranium (with 238 protons and neutrons in its nucleus) spontaneously decay in cosmically short periods of time. But there is reason to think that the binding between protons and neutrons is such that stable elements would be produced if nuclei having about 114 protons and 184 neutrons could be constructed. Such a construction is just beyond our present technology, and clearly beyond the technology of our ancestors. A metal artifact containing such elements would be unambiguous evidence of an advanced extraterrestrial civilization in our past. Or consider the element technetium, whose most stable form has 99 protons and neutrons. Half of it radioactively decays to other elements in about 200,000 years, half of the remainder is gone in another 200,000 years, and so on. As a result, any technetium formed by stars with the other elements billions of years ago must all be gone by now. Thus, terrestrial technetium can only be of artificial origin, as its very name indicates. A technetium artifact could have only one meaning. Similarly, there are common elements on Earth that are immiscible; for example, aluminum and lead. If you melt them together, the lead, being considerably heavier, sinks to the bottom. The aluminum floats to the top. However, in the zero g conditions of spaceflight there is no gravity in the melt to pull the heavier lead down, and exotic alloys such as AL/Pb can be produced. One of the objectives of NASA’s early Shuttle missions will be to test out such alloying techniques. Any message written on an aluminum/lead alloy and retrieved from an ancient civilization would certainly commend itself to our attention today.

It is also possible that the content rather than the material of the message would clearly point to a science or technology beyond the abilities of our ancestors: for example, a vector calculus rendition of Maxwell’s equations (with or without magnetic monopoles), or a graphical representation of the Planck black-body distribution for several different temperatures, or a derivation of the Lorentz transformation of special relativity. Even if the ancient civilization could not understand such writings, they might revere them as holy. But no cases of this sort have emerged-despite what is clearly a profitable market for tales of ancient or modern extraterrestrial astronauts. There have been debates on the purity of magnesium samples from purported crashed UFOs, but their purity was within the competence of American technology at the time of the incident. A supposed star map said to be retrieved (from memory) from the interior of a flying saucer does not, as alleged, resemble the relative positions of the nearest stars like the Sun; in fact, a close examination shows it to be not much better than the “star map” which would be produced if you took an old-fashioned quill pen and splattered a few blank pages with ink spots. With one apparent exception, there are no stories sufficiently detailed to dispose of other explanations and sufficiently accurate to portray correctly modern physics or astronomy to a prescientific or pretechnical people. The one exception is the remarkable mythology surrounding the star Sirius that is held by the Dogon people of the Republic of Mali.

There are at most a few hundred thousand Dogon alive today, and they have been studied intensively by anthropologists only since the 1930s. There are some elements of their mythology that are reminiscent of the legends of the ancient Egyptian civilization, and some anthropologists have assumed a weak Dogon cultural connection with ancient Egypt. The helical risings of Sirius were central to the Egyptian calendar and used to predict the inundations of the Nile. The most striking aspects of Dogon astronomy have been recounted by Marcel Griaule, a French anthropologist working in the 1930s and 1940s. While there is no reason to doubt Griaule’s account, it is important to note that there is no earlier Western record of these remarkable Dogon folk beliefs and that all the information has been funneled through Griaule. The story has recently been popularized by a British writer, R. K. G. Temple.

In contrast to almost all prescientific societies, the Dogon hold that the planets as well as the Earth rotate about their axes and revolve about the Sun. This is a conclusion that can, of course, be achieved without high technology, as Copernicus demonstrated, but it is a very rare insight among the peoples of the Earth. It was taught, however, in ancient Greece by Pythagoras and by Philolaus, who perhaps held, in Laplace’s words, “that the planets were inhabited and that the stars were suns, disseminated in space, being themselves centers of planetary systems.” Such teachings, among a wide variety of contradictory ideas, might be just an inspired lucky guess.

The ancient Greeks believed there were only four elements-earth, fire, water and air-from which all else was constructed. Among the pre-Socratic philosophers there were those who made special advocacy for each one of these elements. If it had later turned out that the universe was indeed made more of one of these elements than another, we should not attribute remarkable prescience to the pre-Socratic philosopher who made the proposal. One of them was bound to be right on statistical grounds alone. In the same way, if we have several hundred or several thousand cultures, each with its own cosmology, we should not be astounded if, every now and then, purely by chance, one of them proposes an idea that is not only correct but also impossible for them to have deduced.

But, according to Temple, the Dogon go further. They hold that Jupiter has four satellites and that Saturn is encircled by a ring. It is perhaps possible that individuals of extraordinary eyesight under superb seeing conditions could, in the absence of a telescope, have observed the Galilean satellites of Jupiter and the rings of Saturn. But this is at the bare edge of plausibility. Unlike every astronomer before Kepler, the Dogon are said to depict the planets moving correctly in elliptical, not circular, orbits.

More striking still is the Dogon belief about Sirius, the brightest star in the sky. They contend that it has a dark and invisible companion star which orbits Sirius (and, Temple says, in an elliptical orbit) once every fifty years. They state that the companion star is very small and very heavy, made of a special metal called “Sagala” which is not found on Earth.

The remarkable fact is that the visible star, Sirius A, does have an extraordinary dark companion, Sirius B, which orbits it in an elliptical orbit once each 50.04 ±0.09 years. Sirius B is the first example of a white dwarf star discovered by modern astrophysics. Its matter is in a state called “relativistically degenerate,” which does not exist on Earth, and since the electrons are not bound to the nuclei in such degenerate matter, it can properly be described as metallic. Since Sirius A is called the Dog Star, Sirius B has sometimes been dubbed “The Pup.”

At first glance the Sirius legend of the Dogon seems to be the best candidate evidence available today for past contact with an advanced extraterrestrial civilization. As we begin a closer look at this story, however, let us remember that the Dogon astronomical tradition is purely oral, that it dates with certainty only from the 1930s and that the diagrams are written with sticks in sand. (Incidentally, there is some evidence that the Dogon like to frame pictures with an ellipse, and that Temple may be mistaken about the claim that the planets and Sirius B move in elliptical orbits in Dogon mythology.)

When we examine the full body of Dogon mythology we find a very rich and detailed structure of legend-much richer, as many anthropologists have remarked, than those of their near geographical neighbors. Where there is a rich array of legends there is, of course, a greater chance of an accidental correspondence of one of the myths with a finding of modern science. A very spare mythology is much less likely to make such an accidental concordance. But when we examine the rest of Dogon mythology, do we find other cases hauntingly reminiscent of some unexpected findings in modern science?

The Dogon cosmogony describes how the Creator examined a plaited basket, round at the mouth and square at the bottom. Such baskets are still in use in Mali today. The Creator up-ended the basket and used it as a model for the creation of the world-the square base represents the sky and the round mouth the Sun. I must say that this account does not strike me as a remarkable anticipation of modern cosmological thinking. In the Dogon representation of the creation of the Earth, the Creator implants in an egg two pairs of twins, each pair comprised of a male and a female. The twins are intended to mature within the egg and fuse to become a single and “perfect” androgynous being. The Earth originates when one of the twins breaks from the egg before maturation, whereupon the Creator sacrifices the other twin in order to maintain a certain cosmic harmony. This is a variegated and interesting mythology, but it does not seem to be qualitatively different from many of the other mythologies and religions of humanity.

The hypothesis of a companion star to Sirius might have followed naturally from the Dogon mythology, in which twins play a central role, but there does not seem to be any explanation this simple about the period and density of the companion of Sirius. The Dogon Sirius myth is too close to modern astronomical thinking and too precise quantitatively to be attributed to chance. Yet there it sits, immersed in a body of more or less standard prescientific legend. What can the explanation be? Is there any chance that the Dogon or their cultural ancestors might actually have been able to see Sirius B and observe its period around Sirius A?

White dwarfs such as Sirius B evolve from stars called red giants, which are very luminous and, it will be no surprise to hear, red. Ancient writers of the first few centuries A.D. actually described Sirius as red-certainly not its color today. In a conversation piece by Horace called “Hoc Quoque Tiresia” (How to Get Rich Quickly) there is a quotation from an unspecified earlier work that says: “The red dog star’s heat split the speechless statues.” As a result of these less than compelling ancient sources there has been a slight temptation among astrophysicists to consider the possibility that the white dwarf Sirius B was a red giant in historical times and visible with the naked eye, completely swamping the light of Sirius A. In that case perhaps there was a slightly later time in the evolution of Sirius B when its brightness was comparable to that of Sirius A, and the relative motion of the two stars about each other could be discerned with the unaided eye. But the best recent information from the theory of stellar evolution suggests that there simply is not enough time for Sirius B to have reached its present white dwarf state if it had been a red giant a few centuries before Horace. What is more, it would seem extraordinary that no one except the Dogon noticed these two stars circling each other every fifty years, each alone being one of the brightest stars in the sky. There was an extremely competent school of observational astronomers in Mesopotamia and in Alexandria in the preceding centuries-to say nothing of the Chinese and Korean astronomical schools-and it would be astonishing if they had noticed nothing. [4] Is our only alternative, then, to believe that representatives of an extraterrestrial civilization have visited the Dogon or their ancestors?

The Dogon have knowledge impossible to acquire without the telescope. The straightforward conclusion is that they had contact with an advanced technical civilization. The only question is, which civilization-extraterrestrial or European? Far more credible than an ancient extraterrestrial educational foray among the Dogon might be a comparatively recent contact with scientifically literate Europeans who conveyed to the Dogon the remarkable European myth of Sirius and its white dwarf companion, a myth that has all the superficial earmarks of a splendidly inventive tall story. Perhaps the Western contact came from a European visitor to Africa, or from the local French schools, or perhaps from contacts in Europe by West Africans inducted to fight for the French in World War I.

The likelihood that these stories arise from contact with Europeans rather than extraterrestrials has been increased by a recent astronomical finding: a Cornell University research team led by James Elliot, employing a high-altitude airborne observatory over the Indian Ocean, discovered in 1977 that the planet Uranus is surrounded by rings-a finding never hinted at by ground-based observations. Advanced extraterrestrial beings viewing our solar system upon approach to Earth would have little difficulty discovering the rings of Uranus. But European astronomers in the nineteenth and early twentieth centuries would have had nothing to say in this regard. The fact that the Dogon do not talk of another planet beyond Saturn with rings suggests to me that their informants were European, not extraterrestrial.

In 1844 the German astronomer F. W. Bessel discovered that the long-term motion of Sirius itself (Sirius A) was not straight but, rather, wavy against the background of more distant stars. Bessel proposed that there was a dark companion to Sirius whose gravitational influence was producing the observed sinusoidal motion. Since the period of the wiggle was fifty years, Bessel deduced that the dark companion had a fifty-year period in the joint motion of Sirius A and B about their common center of mass.

Eighteen years later Alvan G. Clark, during the testing of a new 18½-inch refracting telescope, accidentally discovered the companion, Sirius B, by direct visual observation. From the relative motions, Newtonian gravitational theory permits us to estimate the masses of Sirius A and B. The companion turns out to have a mass just about the same as the Sun’s. But Sirius B is almost ten thousand times fainter than Sirius A, even though their masses are about the same and they are just the same distance from the Earth. These facts can be reconciled only if Sirius B has a much smaller radius or a much lower temperature. But in the late nineteenth century it was believed by astronomers that stars of the same mass had approximately the same temperature, and by the turn of the century it was widely held that the temperature of Sirius B was not remarkably low. Spectroscopic observations by Walter S. Adams in 1915 confirmed this contention. Hence, Sirius B must be very small. We know today that it is only as big as the Earth. Because of its size and color it is called a white dwarf. But if Sirius B is much smaller than Sirius A, its density must be very much greater. Accordingly, the concept of Sirius B as an extremely dense star was widely held in the first few decades of this century.

The peculiar nature of the companion of Sirius was extensively reported in books and in the press. For example, in Sir Arthur Stanley Eddington’s book The Nature of the Physical World, we read: “Astronomical evidence seems to leave practically no doubt that in the so-called white dwarf stars the density of matter far transcends anything of which we have terrestrial experience; in the Companion of Sirius, for example, the density is about a ton to the cubic inch. This condition is explained by the fact that the high temperature and correspondingly intense agitation of the material breaks up (ionises) the outer electron system of the atoms, so that the fragments can be packed much more closely together.” Within a year of its 1928 publication, this book saw ten reprintings in English. It was translated into many languages, including French. The idea that white dwarfs were made of electron degenerate matter had been proposed by R. H. Fowler in 1925 and quickly accepted. On the other hand, the proposal that white dwarfs were made of “relativistically degenerate” matter was first made in the period 1934 to 1937, in Great Britain, by the Indian astrophysicist S. Chandrasekhar; the idea was greeted with substantial skepticism by astronomers who had not grown up with quantum mechanics. One of the most vigorous skeptics was Eddington. The debate was covered in the scientific press and was accessible to the intelligent layman. All this was occurring just before Griaule encountered the Dogon Sirius legend.

In my mind’s eye I picture a Gallic visitor to the Dogon people, in what was then French West Africa, in the early part of this century. He may have been a diplomat, an explorer, an adventurer or an early anthropologist Such people-for example, Richard Francis Burton-were in West Africa many decades earlier. The conversation turns to astronomical lore. Sirius is the brightest star in the sky. The Dogon regale the visitor with their Sirius mythology. Then, smiling politely, expectantly, they inquire of their visitor what his Sirius myths might be. Perhaps he refers before answering to a well-worn book in his baggage. The white dwarf companion of Sirius being a current astronomical sensation, the traveler exchanges a spectacular myth for a routine one. After he leaves, his account is remembered, retold, and eventually incorporated into the corpus of Dogon mythology-or at least into a collateral branch (perhaps filed under “Sirius myths, bleached peoples’ account”). When Marcel Griaule makes mythological inquiries in the 1930s and 1940s, he has his own European Sirius myth played back to him.

THIS FULL-CYCLE RETURN of a myth to its culture of origin through an unwary anthropologist might sound unlikely if there were not so many examples of it in anthropological lore. I here recount a few cases:

In the first decade of the twentieth century a neophyte anthropologist was collecting accounts of ancient traditions from Native American populations in the Southwest. His concern was to write down the traditions, almost exclusively oral, before they vanished altogether. The young Native Americans had already lost appreciable contact with their heritage, and the anthropologist concentrated on elderly members of the tribe. One day he found himself sitting outside a hogan with an aged but lively and cooperative informant.

“Tell me about the ceremonies of your ancestors at the birth of a child.”

“Just one moment.”

The old Indian slowly shuffled into the darkened depths of the hogan. After a fifteen-minute interval he reappeared with a remarkably useful and detailed description of postpartum ceremonials, including rituals connected with breach presentation, afterbirth, umbilical cord, first breath and first cry. Encouraged and writing feverishly, the anthropologist systematically went through the full list of rites of passage, including puberty, marriage, childbearing and death. In each case the informant disappeared into the hogan only to emerge a quarter of an hour later with a rich set of answers. The anthropologist was astonished. Could, he wondered, there be a yet older informant, perhaps infirm and bedriden, within the hogan? Eventually he could resist no longer and summoned the courage to ask his informant what he did at each retreat into the hogan. The old man smiled, withdrew for the last time, and returned clutching a well-thumbed volume of the Dictionary of American Ethnography, which had been compiled by anthropologists in the previous decade. The poor white man, he must have thought, is eager, well-meaning and ignorant. He does not have a copy of this marvelous book which contains the traditions of my people. I shall tell him what it says.

My other two stories recount the adventures of an extraordinary physician, Dr. D. Carleton Gajdusek, who for many years has studied kuru, a rare viral disease, among the inhabitants of New Guinea. For this work he was the recipient of the 1976 Nobel Prize for Medicine. I am grateful to Dr. Gajdusek for taking the trouble to check my memory of his stories, which I first heard from him many years ago. New Guinea is an island on which mountainous terrain separates-in a manner similar to but more completely than the mountains of ancient Greece-one valley people from another. As a result there is a great profusion and variety of cultural traditions.

In the spring of 1957 Gajdusek and Dr. Vincent Zigas, a medical officer with the Public Health Service of what was then called the Territory of Papua and New Guinea, traveled with an Australian administrative patrol officer from the Purosa Valley through the ranges of the South Fore cultural and linguistic-group region to the village of Agakamatasa on an exploratory visit into “uncontrolled territory.” Stone implements were still in use, and there remained a tradition of cannibalism within one’s own living group. Gajdusek and his party found cases of kuru, which is spread by cannibalism (but most often not through the digestive tract), in this most remote of the South Fore villages. They decided to spend a few days, moving into one of the large and traditional wa’e, or men’s houses (the music from one of which, incidentally, was sent to the stars on the Voyager phonograph record). The windowless, low-doored, smoky thatched house was partitioned so that the visitors could neither stand erect nor stretch out. It was divided into many sleeping compartments, each with its own small fire, around which men and boys would huddle in groups to sleep and keep warm during the cold nights at an elevation of more than 6,000 feet, an altitude higher than Denver. To accommodate their visitors, the men and boys gleefully tore out the interior structure of half of the ceremonial men’s house, and during two days and nights of pouring rain Gajdusek and his companions were housebound on a high, windswept, cloud-covered ridge. The young Fore initiates wore bark strands braided into their hair, which was covered with pig grease. They wore huge nose pieces, the penises of pigs as armbands, and the genitalia of opossums and tree-climbing kangaroos as pendants around their necks.

The hosts sang their traditional songs all through the first night and on through the following rainy day. In return, “to enhance our rapport with them,” as Gajdusek says, “we began to sing songs in exchange-among them such Russian songs as ‘Otchi chornye,’ and ‘Moi kostyor v tumane svetit’…” This was received very well, and the Agakamatasa villagers requested many dozens of repetitions in the smoky South Fore longhouse to the accompaniment of the driving rainstorm.

Some years later Gajdusek was engaged in the collection of indigenous music in another part of the South Fore region and asked a group of young men to run through their repertoire of traditional songs. To Gajdusek’s amazement and amusement, they produced a somewhat altered but still clearly recognizable version of “Otchi chornye.” Many of the singers apparently thought the song traditional, and later still Gajdusek found the song imported even farther afield, with none of the singers having any idea of its source.

We can easily imagine some sort of world ethnomusicology survey coming to an exceptionally obscure part of New Guinea and discovering that the natives had a traditional song which sounded in rhythm, music and words remarkably like “Otchi chornye.” If they were to believe that no previous contact of Westerners with these people had occurred, a great mystery could be posited.

Later that same year Gajdusek was visited by several Australian physicians, eager to understand the remarkable findings about the transmission of kuru from patient to patient by cannibalism. Gajdusek described the theories of the origin of many diseases held by the Fore people, who did not believe that illnesses were caused by the spirits of the dead or that malicious deceased relatives, jealous of the living, inflicted disease on those of their surviving kinsmen who offended them, as the pioneering anthropologist Bronislaw Malinowski had recounted for the coastal peoples of Melanesia. Instead, the Fore attributed most diseases to malicious sorcery, which any offended and avenging male, young or old, could execute without the aid of specially trained sorcerers. There was a special sorcery explanation for kuru, but also for chronic lung disease, leprosy, yaws, and so on. These beliefs had been long-established and firmly held, but as the Fore people witnessed yaws yielding entirely to the penicillin injections of Gajdusek and his group, they quickly agreed that the sorcery explanation of yaws was in error and abandoned it; it has never resurfaced in subsequent years. (I wish Westerners would be as quick to abandon obsolete or erroneous social ideas as the Fore of New Guinea.) Modern treatment of leprosy caused its sorcery explanation to disappear as well, although more slowly, and the Fore people today laugh at these backward early opinions on yaws and leprosy. But the traditional views on the origin of kuru have maintained themselves, since the Westerners have been unable to cure or explain, in a manner satisfactory to them, the origin and nature of this disease. Thus, the Fore people remain intensely skeptical of Western explanations for kuru and retain firmly their view that malicious sorcery is the cause.

One of the Australian physicians, visiting an adjacent village with one of Gajdusek’s native informants as translator, spent the day examining kuru patients and independently acquiring information. He returned the same evening to inform Gajdusek that he was mistaken about people not believing in the spirits of the dead as the cause of disease, and that he was further in error in holding that they had abandoned the idea of sorcery as the cause of yaws. The people held, he continued, that a dead body could become invisible and that the unseen spirit of the dead person could enter the skin of a patient at night through an imperceptible break, and induce yaws. The Australian’s informant had even sketched with a stick in the sand the appearance of these ghostly beings. They carefully drew a circle and a few squiggly lines within. Outside the circle, they explained, it was black; inside the circle, bright-a sand portrait of malevolent and pathogenic spirits.

Upon inquiry of the young translator, Gajdusek discovered that the Australian physician had conversed with some of the older men of the village who were well known to Gajdusek and who were often his house and laboratory guests. They had attempted to explain that the shape of the “germ” producing yaws was spiral-the spirochete form they had seen many times through Gajdusek’s dark-field microscope. They had to admit it was invisible-it could be seen only through the microscope-and when pressed by the Australian physician on whether this “represented” the dead person, they had to admit that Gajdusek had stressed that it could be caught from close contact with yaws lesions, as, for example, by sleeping with a person with yaws.

I can well remember the first time I looked through a microscope. After focusing my eyes up near the ocular only to examine my eyelashes, and then peering further into the pitch-black interior of the barrel, I finally managed to look straight down the microscope tube to be dazzled by an illuminated disc of light. It takes a little while for the eye to train itself to examine what is in the disc. Gajdusek’s demonstration to the Fore people was so powerful-after all, the alternatives entirely lacked so concrete a reality-that many accepted his story, even apart from his ability to cure the disease with penicillin. Perhaps some considered the spirochetes in the microscope an amusing example of white-man myth and minor magic, and when another white man arrived querying the origin of disease, they politely returned to him the idea they believed he would be comfortable with. Had Western contact with the Fore people ceased for fifty years, it seems to me entirely possible that a future visitor would discover to his astonishment that the Fore people somehow had knowledge of medical microbiology, despite their largely pretechnological culture.

All three of these stories underline the almost inevitable problems encountered in trying to extract from a “primitive” people their ancient legends. Can you be sure that others have not come before you and destroyed the pristine state of the native myth? Can you be sure that the natives are not humoring you or pulling your leg? Bronislaw Malinowski thought he had discovered a people in the Trobriand Islands who had not worked out the connection between sexual intercourse and childbirth. When asked how children were conceived, they supplied him with an elaborate mythic structure prominently featuring celestial intervention. Amazed, Malinowski objected that was not how it was done at all, and supplied them instead with the version so popular in the West today-including a nine-month gestation period. “Impossible,” replied the Melanesians. “Do you not see that woman over there with her six-month-old child? Her husband has been on an extended voyage to another island for two years.” Is it more likely that the Melanesians were ignorant of the begetting of children or that they were gently chiding Malinowski? If some peculiar-looking stranger came into my town and asked me where babies came from, I’d certainly be tempted to tell him about storks and cabbages. Pre-scientific people are people. Individually they are as clever as we are. Field interrogation of informants from a different culture is not always easy.

I wonder if the Dogon, having heard from a Westerner an extraordinarily inventive myth about the star Sirius-a star already important in their own mythology-did not carefully play it back to the visiting French anthropologist. Is this not more likely than a visit by extraterrestrial spacefarers to ancient Egypt, with one cluster of hard scientific knowledge, in striking contradiction to common sense, preserved by oral tradition, over the millennia, and only in West Africa?

There are too many loopholes, too many alternative explanations for such a myth to provide reliable evidence of past extraterrestrial contact. If there are extraterrestrials, I think it much more likely that unmanned planetary spacecraft and large radiotelescopes will prove to be the means of their detection.

CHAPTER 7

VENUS AND DR. VELIKOVSKY

PROBLEM VIII. THE TEMPERATURE OF VENUS

ANOTHER CURIOUS circumstance concerns the surface temperature of Venus. While the high temperature of Venus is often quoted as a successful prediction and a support of Velikovsky’s hypothesis, the reasoning behind his conclusion and the consequences of his arguments do not seem to be widely known nor discussed.

Let us begin by considering Velikovsky’s views on the temperature of Mars (pages 367-368). He believes that Mars, being a relatively small planet, was more severely affected in its encounters with the more massive Venus and Earth, and therefore that Mars should have a high temperature. He proposes that the mechanism may be “a conversion of motion into heat,” which is a little vague, since heat is precisely the motion of molecules or, much more fantastic, by “interplanetary electrical discharges” which “could also initiate atomic fissions with ensuing radioactivity and emission of heat.”

In the same section, he baldly states, “Mars emits more heat than it receives from the Sun,” in apparent consistency with his collision hypothesis. This statement is, however, dead wrong. The temperature of Mars has been measured repeatedly by Soviet and American spacecraft and by ground-based observers, and the temperatures of all parts of Mars are just what is calculated from the amount of sunlight absorbed by the surface. What is more, this was well known in the 1940s, before Velikovsky’s book was published. And while he mentions four prominent scientists who were involved before 1950 in measuring the temperature of Mars, he makes no reference to their work, and explicitly and erroneously states that they concluded that Mars gave off more radiation than it received from the Sun.

It is difficult to understand this set of errors, and the most generous hypothesis I can offer is that Velikovsky confused the visible part of the electromagnetic spectrum, in which sunlight heats Mars, with the infrared part of the spectrum, in which Mars largely radiates to space. But the conclusion is clear. Mars, even more than Venus, by Velikovsky’s argument should be a “hot planet.” Had Mars proved to be unexpectedly hot, perhaps we would have heard of this as a further confirmation of Velikovsky’s views. But when Mars turns out to have exactly the temperature everyone expected it to have, we do not hear of this as a refutation of Velikovsky’s views. There is a planetary double standard at work.

When we now move on to Venus, we find rather similar arguments brought into play. I find it odd that Velikovsky does not attribute the temperature of Venus to its ejection from Jupiter (see Problem I, above), but he does not. Instead, we are told, because of its close encounter with the Earth and Mars, Venus must have been heated, but also (page 77) “the head of the comet… had passed close to the Sun and was in a state of candescence.” Then, when the comet became the planet Venus, it must still have been “very hot” and have “given off heat” (page ix). Again pre-1950 astronomical observations are referred to (page 370), which show that the dark side of Venus is approximately as hot as the bright side of Venus, to the level probed by middle-infrared radiation. Here Velikovsky accurately quotes the astronomical investigators, and from their work deduces (page 371) “the night side of Venus radiates heat because Venus is hot.” Of course!

What I think Velikovsky is trying to say here is that his Venus, like his Mars, is giving off more heat than it receives from the Sun, and that the observed temperatures on both the night and day sides are due more to the “candescence” of Venus than to the radiation it now receives from the Sun. But this is a serious error. The bolometric albedo (the fraction of sunlight reflected by an object at all wavelengths) of Venus is about 0.73, entirely consistent with the observed infrared temperature of the clouds of Venus of about 240°K; that is to say, the clouds of Venus are precisely at the temperature expected on the basis of the amount of sunlight that is absorbed there.

Velikovsky proposed that both Venus and Mars give off more heat than they receive from the Sun. He is wrong for both planets. In 1949 Kuiper (see References) suggested that Jupiter gives off more heat than it receives, and subsequent observations have proved him right. But of Kuiper’s suggestion Worlds in Collision breathes not a word.

Velikovsky proposed that Venus is hot because of its encounters with Mars and the Earth, and its close passage to the Sun. Since Mars is not anomalously hot, the high surface temperature of Venus must be attributed primarily to the passage of Venus near the Sun during its cometary incarnation. But it is easy to calculate how much energy Venus would have received during its close passage to the Sun and how long it would take for this energy to be radiated away into space. This calculation is performed in Appendix 3, where we find that all of this energy is lost in a period of months to years after the close passage to the Sun, and that there is no chance of any of that heat being retained at the present time in Velikovsky’s chronology. Velikovsky does not mention how close to the Sun Venus is supposed to have passed, but a very close passage compounds the already extremely grave collision physics difficulties outlined in Appendix 1. Incidentally, there is a slight hint in Worlds in Collision that Velikovsky believes that comets shine by emitted rather than reflected light. If so, this may be the source of some of his confusion regarding Venus.

Velikovsky nowhere states the temperature he believed Venus to be at in 1950. As mentioned above, on page 77 he says vaguely that the comet that later became Venus was in a state of “candescence,” but in the preface to the 1965 edition (page xi), he claims to have predicted “an incandescent state of Venus.” This is not at all the same thing, because of the rapid cooling after its supposed solar encounter (Appendix 3). Moreover, Velikovsky himself is proposing that Venus is cooling through time, so what precisely Velikovsky meant by saying that Venus is “hot” is to some degree obscure.

Velikovsky writes in the 1965 preface that his claim of a high surface temperature was “in total disagreement with what was known in 1946.” This turns out to be not quite the case. The dominant figure of Rupert Wildt again looms over the astronomical side of Velikovsky’s hypothesis. Wildt, who, unlike Velikovsky, understood the nature of the problem, predicted correctly that Venus and not Mars would be “hot.” In a 1940 paper in the Astrophysical Journal, Wildt argued that the surface of Venus was much hotter than conventional astronomical opinion had held, because of a carbon-dioxide greenhouse effect. Carbon dioxide had recently been discovered spectroscopically in the atmosphere of Venus, and Wildt correctly pointed out that the observed large quantity of CO₂ would trap infrared radiation given off by the surface of the planet until the surface temperature rose to a higher value, so that the incoming visible sunlight just balanced the outgoing infrared planetary emission. Wildt calculated that the temperature would be almost 400°K, or around the normal boiling point of water (373°K = 212 °F = 100°C). There is no doubt that this was the most careful treatment of the surface temperature of Venus prior to the 1950s, and it is again odd that Velikovsky, who seems to have read all papers on Venus and Mars published in the Astrophysical Journal in the 1920s, 1930s and 1940s, somehow overlooked this historically significant work.

We now know from ground-based radio observations and from the remarkably successful direct entry and landing probes of the Soviet Union that the surface temperature of Venus is within a few degrees of 750°K (Marov, 1972). The surface atmospheric pressure is about ninety times that at the surface of the Earth, and is comprised primarily of carbon dioxide. This large abundance of carbon dioxide, plus the smaller quantities of water vapor which have been detected on Venus, are adequate to heat the surface to the observed temperature via the greenhouse effect. The Venera 8 descent module, the first spacecraft to land on the illuminated hemisphere of Venus, found it illuminated at the surface, and the Soviet experimenters concluded that the amount of sunlight reaching the surface and the atmospheric constitution were together adequate to drive the required radiative-convective greenhouse (Marov, et al., 1973). These results were confirmed by the Venera 9 and 10 missions, which obtained clear photographs, in sunlight, of surface rocks. Velikovsky is thus certainly mistaken when he says (page ix) “light does not penetrate the cloud cover,” and is probably mistaken when he says (page ix) the “greenhouse effect could not explain so high a temperature.” These conclusions received important additional support late in 1978 from the U.S. Pioneer Venus mission.

A repeated claim by Velikovsky is that Venus is cooling off with time. As we have seen, he attributes its high temperature to solar heating during a close solar passage. In many publications Velikovsky compares published temperature measurements of Venus, made at different times, and tries to show the desired cooling. An unbiased presentation of the microwave brightness temperatures of Venus-the only nonspacecraft data that apply to the surface temperature of the planet-are exhibited in Figure 1. The error bars represent the uncertainties in the measurement processes as estimated by the radio observers themselves. We see that there is not the faintest hint of a decline in temperature with time (if anything, there is a suggestion of an increase with time, but the error bars are sufficiently large that such a conclusion is also unsupported by the data). Similar results apply to measurements, in the infrared part of the spectrum, of cloud temperatures: they are lower in magnitude and do not decline with time. Moreover, the simplest considerations of the solution of the one-dimensional equation of heat conduction show that in the Velikovskian scenario essentially all the cooling by radiation to space would have occurred long ago. Even if Velikovsky were right about the source of the high Venus surface temperatures, his prediction of a secular temperature decrease would be erroneous.

FIGURE 1. Microwave brightness temperatures of Venus as a function of time (after a compilation by D. Morrison). There is certainly no evidence of a declining surface temperature. The wavelength of observation is denoted by Λ.

The high surface temperature of Venus is another of the so-called proofs of the Velikovsky hypothesis. We find that (1) the temperature in question was never specified; (2) the mechanism proposed for providing this temperature is grossly inadequate; (3) the surface of the planet does not cool off with time as advertised; and (4) the idea of a high surface temperature on Venus was published in the dominant astronomical journal of its time and with an essentially correct argument ten years before the publication of Worlds in Collision.

CHAPTER 8

THROUGHOUT human history there have been attempts to contrive rational arguments to convince skeptics of the existence of a God or gods. But most theologians have held that the ultimate reality of divine beings is a matter for faith alone and is inaccessible to rational endeavor. St. Anselm argued that since we can imagine a perfect being, he must exist-because he would not be perfect without the added perfection of existence. This so-called ontological argument was more or less promptly attacked on two grounds: (1) Can we imagine a completely perfect being? (2) Is it obvious that perfection is augmented by existence? To the modern ear such pious arguments seem to be about words and definitions rather than about external reality.

More familiar is the argument from design, an approach that penetrates deeply into issues of fundamental scientific concern. This argument was admirably summarized by David Hume: “Look round the world: contemplate the whole and every part of it; you will find it to be nothing but one great machine, subdivided into an infinite number of lesser machines… All these various machines, even their most minute parts, are adjusted to each other with an accuracy which ravishes into admiration all men who have ever contemplated them. The curious adapting of means to ends, throughout all nature, resembles exactly, though it much exceeds, the production of human contrivance; of human design, thought, wisdom, and intelligence. Since therefore the effects resemble each other, we are led to infer, by all the rules of analogy, that the causes also resemble; and that the Author of Nature is somewhat similar to the mind of man; though possessed of much larger faculties proportioned to the grandure of the work which he has executed.”

Hume then goes on to subject this argument, as did Immanuel Kant after him, to a devastating and compelling attack, notwithstanding which the argument from design continued to be immensely popular-as, for example, in the works of William Paley-through the early nineteenth century. A typical passage by Paley goes: “There cannot be a design without a designer; contrivance without a contrivor; order without choice; arrangement without anything capable of arranging; subserviency and relation to a purpose, without that which could intend a purpose; means suitable to an end, and executing their office and accomplishing that end, without the end ever having been contemplated, or the means accommodated to it. Arrangement, disposition of parts, subserviency of means to an end, relation of instruments to a use, imply the presence of intelligence and mind.”

It was not until the development of modern science, but most particularly the brilliant formulation of the theory of evolution by natural selection, put forth by Charles Darwin and Alfred Russel Wallace in 1859, that these apparently plausible arguments were fatally undermined.

There can, of course, be no disproof of the existence of God-particularly a sufficiently subtle God. But it is a kindness neither to science nor religion to leave unchallenged inadequate arguments for the existence of God. Moreover, debates on such questions are good fun, and at the very least, hone the mind for useful work. Not much of this sort of disputation is in evidence today, perhaps because new arguments for the existence of God which can be understood at all are exceedingly rare. One recent and modern version of the argument from design was kindly sent to me by its author, perhaps to secure constructive criticism.

NORMAN BLOOM is a contemporary American who incidentally believes himself to be the Second Coming of Jesus Christ. Bloom observes in Scripture and everyday life numerical coincidences which anyone else would consider meaningless. But there are so many such coincidences that, Bloom believes, they can be due only to an unseen intelligence, and the fact that no one else seems to be able to find or appreciate such coincidences convinces Bloom that he has been chosen to reveal God’s presence. Bloom has been a fixture at some scientific meetings where he harangues the hurrying, preoccupied crowds moving from session to session. Typical Bloom rhetoric is “And though you reject me, and scorn me, and deny me, YET ALL WILL BE BROUGHT ONLY BY ME. My will will be, because I have formed you out of the nothingness. You are the Creation of My Hands. And I will complete My Creation and Complete My Purpose that I have Purposed from of old. I AM THAT I AM. I AM THE LORD THY GOD IN TRUTH.” He is nothing if not modest, and the capitalization conventions are entirely his.

Bloom has issued a fascinating pamphlet, which states: “The complete faculty of Princeton University (including its officers and its deans and the chairmen of the departments listed here) has agreed that it cannot refute, nor show in basic error the proof brought to it, in the book, The New World dated Sept. 1974. This faculty acknowledges as of June 1, 1975 that it accepts as a proven truth THE IRREFUTABLE PROOF THAT AN ETERNAL MIND AND HAND HAS SHAPED AND CONTROLLED THE HISTORY OF THE WORLD THROUGH THOUSANDS OF YEARS.” A closer reading shows that despite Bloom’s distributing his proofs to over a thousand faculty members of Princeton University, and despite his offer of a $1,000 prize for the first individual to refute his proof, there was no response whatever. After six months he concluded that since Princeton did not answer, Princeton believed. Considering the ways of university faculty members, an alternative explanation has occurred to me. In any case, I do not think that the absence of a reply constitutes irrefutable support for Bloom’s arguments.

Princeton has apparently not been alone in treating Bloom inhospitably: “Yes, times almost without number, I have been chased by police for bringing you the gift of my writing… Is it not so that professors at a university are supposed to have the maturity and judgment and wisdom to be able to read a writing and determine for themselves the value of its contents? Is it that they require THOUGHT CONTROL POLICE to tell them what they should or should not read or think about? But, even at the astronomy department of Harvard University, I have been chased by police for the crime of distributing that New World Lecture, an irrefutable proof that the earth-moon-sun system is shaped by a controlling mind and hand. Yes, and THREATENED WITH IMPRISONMENT, IF I DARE BESMIRCH THE HARVARD CAMPUS WITH MY PRESENCE ONCE MORE… AND THIS IS THE UNIVERSITY THAT HAS UPON ITS SHIELD THE WORD VERITAS: VERITAS: VERITAS:-Truth, Truth, Truth. Ah, what hypocrites and mockers you are!”

The supposed proofs are many and diverse, all involving numerical coincidences which Bloom believes could not be due to chance. Both in style and content, the arguments are reminiscent of Talmudic textual commentary and cabalistic lore of the Jewish Middle Ages: for example, the angular size of the Moon or the Sun as seen from the Earth is half a degree. This is just 1/720 of the circle (360°) of the sky. But 720 = 6! = 6 × 5 × 4 × 3 × 2 × 1. Therefore, God exists. It is an improvement on Euler’s proof to Diderot, but the approach is familiar and infiltrates the entire history of religion. In 1658 Gaspar Schott, a Jesuit priest, announced in his Magia Universalis Naturae et Artis that the number of degrees of grace of the Virgin Mary is 2²⁵⁶ = 2²⁸ 1.2 × 10⁷⁷ (which, by and by, is very roughly the number of elementary particles in the universe).

Another Bloomian argument is described as “irrefutable proof that the God of Scripture is he who has shaped and controlled the history of the world through thousands of years.” The argument is this: according to Chapters 5 and 11 of Genesis, Abraham was born 1,948 years after Adam, at a time when Abraham’s father, Terah, was seventy years old. But the Second Temple was destroyed by the Romans in A.D. 70, and the State of Israel was created in A.D. 1948 Q.E.D. It is hard to escape the impression that there may be a flaw in the argument somewhere. “Irrefutable” is, after all, a fairly strong word. But the argument is a refreshing diversion from St. Anselm.

Bloom’s central argument, however, and the one that much of the rest is based upon, is the claimed astronomical coincidence that 235 new moons is, with spectacular accuracy, just as long as nineteen years. Whence: “Look, mankind, I say to you all, in essence you are living in a clock. The clock keeps perfect time, to an accuracy of one second/day!… How could such a clock in the heavens come to be without there being some being, who with perception and understanding, who, with a plan and with the power, could form that clock?”

A fair question. To pursue it we must realize that there are several different kinds of years and several different kinds of months in use in astronomy. The sidereal year is the period that the Earth takes to go once around the Sun with respect to the distant stars. It equals 365.2564 days. (The days we will use, as Norman Bloom does, are what astronomers call “mean solar days.”) Then there is the tropical year. It is the period for the Earth to make one circuit about the Sun with respect to the seasons, and equals 365.242199 days. The tropical year is different from the sidereal year because of the precession of the equinoxes, the slow toplike movement of the Earth produced by the gravitational forces of the Sun and the Moon on its oblate shape. Finally, there is the so-called anomalistic year of 365.2596 days. It is the interval between two successive closest approaches of the Earth to the Sun, and is different from the sidereal year because of the slow movement of the Earth’s elliptical orbit in its own plane, produced by gravitational tugs by the nearby planets.

Likewise, there are several different kinds of months. The word “month,” of course, comes from “moon.” The sidereal month is the time for the Moon to go once around the earth with respect to the distant stars and equals 27.32166 days. The synodic month, also called a lunation, is the time from new moon to new moon or full moon to full moon. It is 29.530588 days. The synodic month is different from the sidereal month because, in the course of one sidereal revolution of the Moon about the Earth, the Earth-Moon system has together revolved a little bit (about one-thirteenth) of the way around the Sun. Therefore the angle by which the Sun illuminates the Moon has changed from our terrestrial vantage point. Now, the plane of the Moon’s orbit around the Earth intersects the plane of the Earth’s orbit around the Sun at two places-opposite to each other-called the nodes of the Moon’s orbit. A nodical or draconic month is the time for the Moon to move from one node back around again to the same node and equals 27.21220 days. These nodes move, completing one apparent circuit, in 18.6 years because of gravitational tugs, chiefly by the Sun. Finally, there is the anomalistic month of 27.55455 days, which is the time for the Moon to complete one circuit of the Earth with respect to the nearest point in its orbit. A little table on these various definitions of the year and the month is shown below.

KINDS OF YEARS AND MONTHS, EARTH-MOON SYSTEM

Now, Bloom’s main proof of the existence of God depends upon choosing one of the sorts of years, multiplying it by 19 and then dividing by one of the sorts of months. Since the sidereal, tropical and anomalistic years are so close together in length, we get sensibly the same answer whichever one we choose. But the same is not true for the months. There are four different kinds of months, and each gives a different answer. If we ask how many synodic months there are in nineteen sidereal years, we find the answer to be 253.00621, as advertised; and it is the closeness of this result to a whole number that is the fundamental coincidence of Bloom’s thesis. Bloom, of course, believes it to be no coincidence.

But if we were to ask instead how many sidereal months there are in nineteen sidereal years we would find the answer to be 254.00622; for nodical months, 255.02795; and for anomalistic months, 251.85937. It is certainly true that the synodic month is the one most strikingly apparent to a naked-eye observer, but I nevertheless have the impression that one could construct equally elaborate theological speculations on 252, 254, or 255 as on 235.

We must now ask where the number 19 comes from in this argument. Its only justification is David’s lovely Nineteenth Psalm, which begins: “The heavens declare the glory of God, and the firmament sheweth his handiwork. Day unto day uttereth speech, and night unto night sheweth knowledge.” This seems quite an appropriate quotation from which to find a hint of an astronomical proof for the existence of God. But the argument assumes what it intends to prove. The argument is also not unique. Consider, for example, the Eleventh Psalm, also written by David. In it we find the following words, which may equally well bear on this question: “The Lord is in his holy temple, the Lord’s throne is in heaven: his eyes behold, his eyelids try, the children of men,” which is followed in the following Psalm with “the children of men… speak vanity.” Now, if we ask how many synodic months there are in eleven sidereal years (or 4017.8204 mean solar days), we find the answer to be 136.05623. Thus, just as there seems to be a connection between nineteen years and 235 new moons, there is a connection between eleven years and 136 new moons. Moreover, the famous British astronomer Sir Arthur Stanley Eddington believed that all of physics could be derived from the number 136. (I once suggested to Bloom that with the foregoing information and just a little intellectual fortitude it should be possible as well to reconstruct all of Bosnian history.)

One numerical coincidence of this sort, which is of deep significance, was well known to the Babylonians, contemporaries of the ancient Hebrews. It is called the Saros. It is the period between two successive similar cycles of eclipses. In a solar eclipse the Moon, which appears from the Earth just as large (1/2°) as the Sun, must pass in front of it. For a lunar eclipse, the Earth’s shadow in space must intercept the Moon. For either kind of eclipse to occur, the Moon must, first of all, be either new or full-so that the Earth, the Moon and the Sun are in a straight line. Therefore the synodic month is obviously involved in the periodicity of eclipses. But for an eclipse to occur, the Moon must also be near one of the nodes of its orbit. Therefore the nodical month is involved. It turns out that 233 synodic months is equal to 241.9989 (or very close to 242) nodical months. This is the equivalent of a little over eighteen years and ten or eleven days (depending on the number of intervening leap days), and comprises the Saros. Coincidence?

Similar numerical coincidences are in fact common throughout the solar system. The ratio of spin period to orbital period on Mercury is 3 to 2. Venus manages to turn the same face to the Earth at its closest approach on each of its revolutions around the Sun. A particle in the gap between the two principal rings of Saturn, called the Cassini Division, would orbit Saturn in a period just half that of Mimas, its second satellite. Likewise, in the asteroid belt there are empty regions, known as the Kirkwood Gaps, which correspond to nonexistent asteroids with periods half that of Jupiter, one-third, two-fifths, three-fifths, and so on.

None of these numerical coincidences proves the existence of God-or if it does, the argument is subtle, because these effects are due to resonances. For example, an asteroid that strays into one of the Kirkwood Gaps experiences a periodic gravitational pumping by Jupiter. Every two times around the Sun for the asteroid, Jupiter makes exactly one circuit. There it is, tugging away at the same point in the asteroid’s orbit every revolution. Soon the asteroid is persuaded to vacate the gap. Such incommensurable ratios of whole numbers are a general consequence of gravitational resonance in the solar system. It is a kind of perturbational natural selection. Given enough time-and time is what the solar system has a great deal of-such resonances will arise inevitably.

That the general result of planetary perturbations is stable resonances and not catastrophic collisions was first shown from Newtonian gravitational theory by Pierre Simon, Marquis de Laplace, who described the solar system as “a great pendulum of eternity, which beats ages as a pendulum beats seconds.” Now, the elegance and simplicity of Newtonian gravitation might be used as an argument for the existence of God. We could imagine universes with other gravitational laws and much more chaotic planetary interactions. But in many of those universes we would not have evolved-precisely because of the chaos. Such gravitational resonances do not prove the existence of God, but if he does exist, they show, in the words of Einstein, that, while he may be subtle, he is not malicious.

BLOOM CONTINUES his work. He has, for example, demonstrated the preordination of the United States of America by the prominence of the number 13 in major league baseball scores on July 4, 1976. He has accepted my challenge and made an interesting attempt to derive some of Bosnian history from numerology-at least the assassination of Archduke Ferdinand at Sarajevo, the event that precipitated World War I. One of his arguments involves the date on which Sir Arthur Stanley Eddington presented a talk on his mystical number 136 at Cornell University, where I teach. And he has even performed some numerical manipulations using my birth date to demonstrate that I also am part of the cosmic plan. These and similar cases convince me that Bloom can prove anything.

Norman Bloom is, in fact, a kind of genius. If enough independent phenomena are studied and correlations sought, some will of course be found. If we know only the coincidences and not the enormous effort and many unsuccessful trials that preceded their discovery, we might believe that an important finding has been made. Actually, it is only what statisticians call “the fallacy of the enumeration of favorable circumstances.” But to find as many coincidences as Norman Bloom has requires great skill and dedication. It is in a way a forlorn and perhaps even hopeless objective-to demonstrate the existence of God by numerical coincidences to an uninterested, to say nothing of a mathematically unenlightened public. It is easy to imagine the contributions Bloom’s talents might have made in another field. But there is something a little glorious, I find, in his fierce dedication and very considerable arithmetic intuition. It is a combination of talents which is, one might almost say, God-given.

CHAPTER 9

BY THE TIME I was ten I had decided-in almost total ignorance of the difficulty of the problem-that the universe was full up. There were too many places for this to be the only inhabited planet. And judging from the variety of life on Earth (trees looked pretty different from most of my friends), I figured life elsewhere would look very strange. I tried hard to imagine what that life would be like, but despite my best efforts I always produced a kind of terrestrial chimaera, a blend of existing plants and animals.

About this time a friend introduced me to the Mars novels of Edgar Rice Burroughs. I had not thought much about Mars before, but here, presented before me in the adventures of John Carter, was an inhabited extraterrestrial world breathtakingly fleshed out: ancient sea bottoms, great canal-pumping stations and a variety of beings, some of them exotic. There were, for example, the eight-legged beasts of burden, the thoats.

These novels were exhilarating to read. At first. Then slowly doubts began to gnaw. The plot surprise in the first John Carter novel I read hinged on him forgetting that the year is longer on Mars than on Earth. But it seemed to me that if you go to another planet, one of the first things you check into is the length of the day and the year. (Incidentally, I can recall no mention by Carter of the remarkable fact that the Martian day is almost as long as the terrestrial day. It was as if he expected the familiar features of his home planet somewhere else.) Then there were incidental remarks made which were at first stunning but on sober reflection disappointing. For example, Burroughs casually comments that on Mars there are two more primary colors than on Earth. I spent many long minutes with my eyes tightly closed, fiercely concentrating on a new primary color. But it would always be a murky brown or a plum. How could there be another primary color on Mars, much less two? What was a primary color? Was it something to do with physics or something to do with physiology? I decided that Burroughs might not have known what he was talking about, but he certainly made his readers think. And in those many chapters where there was not much to think about, there were satisfyingly malignant enemies and rousing swordsmanship-more than enough to maintain the interest of a citybound ten-year-old in a Brooklyn summer.

A year later, by sheerest accident, I stumbled across a magazine called Astounding Science Fiction in the neighborhood candy store. A glance at the cover and a quick riffle through the interior showed me it was what I had been looking for. With some effort I managed to scrape together the purchase price, opened it at random, sat down on a bench not twenty feet from the candy store and read my first modern science-fiction short story, “Pete Can Fix It,” by Raymond F. Jones, a gentle time-travel story of post-nuclear-war holocaust. I knew about the atom bomb-I remember an excited friend explaining to me that it was made of atoms-but this was the first I had seen about the social implications of the development of nuclear weapons. It got you thinking. The little device, though, that Pete the garage mechanic put on automobiles so passers-by might make brief cautionary trips into the wasteland of the future-what was that little device? How was it made? How could you get into the future and then come back? If Raymond F. Jones knew, he wasn’t telling.

I found I was hooked. Each month I eagerly awaited the arrival of Astounding. I read Jules Verne and H. G. Wells, read from cover to cover the first two science-fiction anthologies that I was able to find, made scorecards, similar to those I was fond of making for baseball, on the quality of the stories I read. Many of the stories ranked high in asking interesting questions but low in answering them.

There is still a part of me that is ten years old. But by and large I’m older. My critical faculties and perhaps even my literary tastes have improved. In rereading L. Ron Hubbard’s The End Is Not Yet, which I had first read at age fourteen, I was so amazed at how much worse it was than I had remembered that I seriously considered the possibility that there were two novels of the same name and by the same author but of vastly differing quality. I can no longer manage credulous acceptance as well as I used to. In Larry Niven’s Neutron Star the plot hinges on the astonishing tidal forces exerted by a strong gravitational field. But we are asked to believe that hundreds or thousands of years from now, at a time of casual interstellar spaceflight, such tidal forces have been forgotten. We are asked to believe that the first probe of a neutron star is done by a manned rather than by an unmanned spacecraft. We are asked too much. In a novel of ideas, the ideas have to work.

I had the same kind of disquieting feelings many years earlier on reading Verne’s description that weightlessness on a lunar voyage occurred only at the point in space where the Earth’s and the Moon’s gravitational pulls canceled, and in Wells’s invention of the antigravity mineral cavorite: Why should a vein of cavorite still be on Earth? Shouldn’t it have flung itself into space long ago? In Douglas Trumbull’s technically proficient science-fiction film Silent Running, the trees in vast closed spaceborne ecological systems are dying. After weeks of painstaking study and agonizing searches through botany texts, the solution is found: plants, it turns out, need sunlight. Trumbull’s characters are able to build interplanetary cities but have forgotten the inverse square law. I was willing to overlook the portrayal of the rings of Saturn as pastel-colored gases, but not this.

I have the same trouble with Star Trek, which I know has a wide following and which some thoughtful friends tell me I should view allegorically and not literally. But when astronauts from Earth set down on some fardistant planet and find the human beings there in the midst of a conflict between two nuclear superpowers-which call themselves the Yangs and the Coms, or their phonetic equivalents-the suspension of disbelief crumbles. In a global terrestrial society centuries in the future, the ship’s officers are embarrassingly Anglo-American. Only two of twelve or fifteen interstellar vessels are given non-English names, Kongo and Potemkin. (Potemkin and not Aurora?) And the idea of a successful cross between a “Vulcan” and a terrestrial simply ignores what we know of molecular biology. (As I have remarked elsewhere, such a cross is about as likely as the successful mating of a man and a petunia.) According to Harlan Ellison, even such sedate biological novelties as Mr. Spock’s pointy ears and permanently querulous eyebrows were considered by network executives far too daring; such enormous differences between Vulcans and humans would only confuse the audience, they thought, and a move was made to have all physiologically distinguishing Vulcanian features effaced. I have similar problems with films in which familiar creatures, slightly changed-spiders thirty feet tall-are menacing the cities of the Earth: since insects and arachnids breathe by diffusion, such marauders would asphyxiate before they could savage their first city.

I believe that the same thirst for wonder is inside me that was there when I was ten. But I have learned since then a little bit about how the world is really put together. I find that science fiction has led me to science. I find science more subtle, more intricate and more awesome than much of science fiction. Think of some of the scientific findings of the last few decades: that Mars is covered with ancient dry rivers; that apes can learn languages of many hundreds of words, understand abstract concepts and construct new grammatical usages; that there are particles that pass effortlessly through the entire Earth so that we see as many of them coming up through our feet as down from the sky; that in the constellation Cygnus there is a double star, one of whose components has such a high gravitational acceleration that light cannot escape from it: it may be blazing with radiation on the inside but it is invisible from the outside. In the face of all this, many of the standard ideas of science fiction seem to me to pale by comparison. I see the relative absence of these things and the distortions of scientific thinking often encountered in science fiction as terrible wasted opportunities. Real science is as amenable to exciting and engrossing fiction as fake science, and I think it is important to exploit every opportunity to convey scientific ideas in a civilization which is both based upon science and does almost nothing to ensure that science is understood.

But the best of science fiction remains very good indeed. There are stories so tautly constructed, so rich in accommodating details of an unfamiliar society that they sweep me along before I even have a chance to be critical. Such stories include Robert Heinlein’s The Door into Summer, Alfred Bester’s The Stars My Destination and The Demolished Man, Jack Finney’s Time and Again, Frank Herbert’s Dune and Walter M. Miller’s A Canticle for Leibowitz. You can ruminate over the ideas in these books. Heinlein’s asides on the feasibility and social utility of household robots wear exceedingly well over the years. The insights into terrestrial ecology provided by hypothetical extraterrestrial ecologies as in Dune perform, I think, an important social service. He Who Shrank, by Harry Hasse, presents an entrancing cosmological speculation which is being seriously revived today, the idea of an infinite regress of universes-in which each of our elementary particles is a universe one level down, and in which we are an elementary particle in the next universe up.

A rare few science-fiction novels combine extraordinarily well a deep human sensitivity with a standard science-fiction theme. I am thinking, for example, of Algis Budrys’ Rogue Moon, and of many of the works of Ray Bradbury and Theodore Sturgeon-for example, the latter’s To Here and the Easel, a stunning portrayal of schizophrenia as perceived from the inside, as well as a provocative introduction to Ariosto’s Orlando Furioso.

There was once a subtle science-fiction story by the astronomer Robert S. Richardson on the continuous-creation origin of cosmic rays. Isaac Asimov’s story Breathes There a Man provided a poignant insight into the emotional stress and sense of isolation of some of the best theoretical scientists. Arthur C. Clarke’s The Nine Billion Names of God introduced many Western readers to an intriguing speculation in Oriental religions.

One of the great benefits of science fiction is that it can convey bits and pieces, hints and phrases, of knowledge unknown or inaccessible to the reader. Heinlein’s And He Built a Crooked House was for many readers probably the first introduction they had ever encountered to four-dimensional geometry that held any promise of being comprehensible. One science-fiction work actually presents the mathematics of Einstein’s last attempt at a unified field theory; another presents an important equation in population genetics. Asimov’s robots were “positronic,” because the positron had recently been discovered. Asimov never provided any explanation of how positrons run robots, but his readers had now heard of positrons. Jack Williamson’s rhodomagnetic robots were run off ruthenium, rhodium and palladium, the next Group VIII metals after iron, nickel and cobalt in the periodic table. An analogue with ferromagnetism was suggested. I suppose that there are science-fiction robots today that are quark-ish or charming and will provide some brief verbal entrée into the excitement of contemporary elementary particle physics. L. Sprague de Camp’s Lest Darkness Fall is an excellent introduction to Rome at the time of the Gothic invasion, and Asimov’s Foundation series, although this is not explained in the books, offers a very useful summary of some of the dynamics of the far-flung imperial Roman Empire. Time-travel stories-for example, the three remarkable efforts by Heinlein, All You Zombies, By His Bootstraps and The Door into Summer-force the reader into contemplations of the nature of causality and the arrow of time. They are books you ponder over as the water is running out of the bathtub or as you walk through the woods in an early winter snowfall.

Another great value of modern science fiction is some of the art forms it elicits. A fuzzy imagining in the mind’s eye of what the surface of another planet might look like is one thing, but examining a meticulous painting of the same scene by Chesley Bonestell in his prime is quite another. The sense of astronomical wonder is splendidly conveyed by the best of such contemporary artists-Don Davis, Jon Lomberg, Rick Sternbach, Robert McCall. And in the verse of Diane Ackerman can be glimpsed the prospect of a mature astronomical poetry, fully conversant with standard science-fiction themes.

Science-fiction ideas are widespread today in somewhat different guises. We have science-fiction writers such as Isaac Asimov and Arthur C. Clarke providing cogent and brilliant summaries in nonfictional form of many aspects of science and society. Some contemporary scientists are introduced to a vaster public by science fiction. For example, in the thoughtful novel The Listeners, by James Gunn, we find the following comment made fifty years from now about my colleague, the astronomer Frank Drake: “Drake! What did he know?” A great deal, it turns out. We also find straight science fiction disguised as fact in a vast proliferation of pseudoscientific writings, belief systems and organizations.

One science-fiction writer, L. Ron Hubbard, has founded a successful cult called Scientology-invented, according to one account, overnight on a bet that he could do as well as Freud, invent a religion and make money from it. Classic science-fiction ideas are now institutionalized in unidentified flying objects and ancient-astronaut belief systems-although I have difficulty not concluding that Stanley Weinbaum (in The Valley of Dreams) did it better, as well as earlier, than Erich von Däniken. R. De Witt Miller in Within the Pyramid manages to anticipate both von Däniken and Velikovsky, and to provide a more coherent hypothesis on the supposed extraterrestrial origin of pyramids than can be found in all the writings on ancient astronauts and pyramidology. In Wine of the Dreamers, by John D. MacDonald (a science-fiction author now transmogrified into one of the most interesting contemporary writers of detective fiction), we find the sentence “and there are traces, in Earth mythology… of great ships and chariots that crossed the sky.” The story Farewell to the Master, by Harry Bates, was converted into a motion picture, The Day the Earth Stood Still (which abandoned the essential plot element, that on the extraterrestrial spacecraft it was the robot and not the human who was in command). The movie, with its depiction of a flying saucer buzzing Washington, is thought by some sober investigators to have played a role in the 1952 Washington, D.C., UFO “flap” which followed closely the release of the motion picture. Many popular novels today of the espionage variety, in the shallowness of their characterizations and the gimmickry of their plots, are virtually indistinguishable from pulp science fiction of the ’30s and ’40s.

THE INTERWEAVING of science and science fiction sometimes produces curious results. It is not always clear whether life imitates art or vice versa. For example, Kurt Vonnegut, Jr., has written a superb epistemological novel, The Sirens of Titan, in which a not altogether inclement environment is postulated on Saturn’s largest moon. When in the last few years some planetary scientists, myself among them, presented evidence that Titan has a dense atmosphere and perhaps higher temperatures than expected, many people commented to me on the prescience of Kurt Vonnegut. But Vonnegut was a physics major at Cornell University and naturally knowledgeable about the latest findings in astronomy. (Many of the best science-fiction writers have science or engineering backgrounds; for example, Poul Anderson, Isaac Asimov, Arthur C. Clarke, Hal Clement and Robert Heinlein.) In 1944, an atmosphere of methane was discovered on Titan, the first satellite in the solar system known to have an atmosphere. In this, as in many similar cases, art imitates life.

The trouble has been that our understanding of the other planets has been changing faster than the science-fiction representations of them. A clement twilight zone on a synchronously rotating Mercury, a swamp-and-jungle Venus and a canal-infested Mars, while all classic science-fiction devices, are all based upon earlier misapprehensions by planetary astronomers. The erroneous ideas were faithfully transcribed into science-fiction stories, which were then read by many of the youngsters who were to become the next generation of planetary astronomers-thereby simultaneously capturing the interest of the youngsters and making it more difficult to correct the misapprehensions of the oldsters. But as our knowledge of the planets has changed, the environments in the corresponding science-fiction stories have also changed. It is quite rare to find a science-fiction story written today that involves algae farms on the surface of Venus. (Incidentally, the UFO-contact mythologizers are slower to change, and we can still find accounts of flying saucers from a Venus populated by beautiful human beings in long white robes inhabiting a kind of Cytherean Garden of Eden. The 900° Fahrenheit temperatures of Venus give us one way of checking such stories.) Likewise, the idea of a “space warp” is a hoary science-fiction standby but it did not arise in science fiction. It arose from Einstein’s General Theory of Relativity.

The connection between science-fiction depictions of Mars and the actual exploration of Mars is so close that, subsequent to the Mariner 9 mission to Mars, we were able to name a few Martian craters after deceased science-fiction personalities. (See Chapter 11.) Thus there are on Mars craters named after H. G. Wells, Edgar Rice Burroughs, Stanley Weinbaum and John W. Campbell, Jr. These names have been officially approved by the International Astronomical Union. No doubt other science-fiction personalities will be added soon after they die.

THE GREAT INTEREST of youngsters in science fiction is reflected in films, television programs, comic books and a demand for science-fiction courses in high schools and colleges. My experience is that such courses can be fine educational experiences or disasters, depending on how they are done. Courses in which the readings are selected by the students provide no opportunity for the students to read what they have not already read. Courses in which there is no attempt to extend the science-fiction plot line to encompass the appropriate science miss a great educational opportunity. But properly planned science-fiction courses, in which science or politics is an integral component, would seem to me to have a long and useful life in school curricula.

The greatest human significance of science fiction may be as experiments on the future, as explorations of alternative destinies, as attempts to minimize future shock. This is part of the reason that science fiction has so wide an appeal among young people: it is they who will live in the future. It is my firm view that no society on Earth today is well adapted to the Earth of one or two hundred years from now (if we are wise enough or lucky enough to survive that long). We desperately need an exploration of alternative futures, both experimental and conceptual. The novels and stories of Eric Frank Russell were very much to this point. In them, we were able to see conceivable alternative economic systems or the great efficiency of a unified passive resistance to an occupying power. In modern science fiction, useful suggestions can also be found for making a revolution in a computerized technological society, as in Heinlein’s The Moon Is a Harsh Mistress.

Such ideas, when encountered young, can influence adult behavior. Many scientists deeply involved in the exploration of the solar system (myself among them) were first turned in that direction by science fiction. And the fact that some of that science fiction was not of the highest quality is irrelevant. Ten-year-olds do not read the scientific literature.

I do not know if time travel into the past is possible. The causality problems it would imply make me very skeptical. But there are those who are thinking about it. What are called closed time-like lines-routes in space-time permitting unrestricted time travel-appear in some solutions to the general relativistic field equations. A recent claim, perhaps mistaken, is that closed timelike lines appear in the vicinity of a large, rapidly rotating cylinder. I wonder to what extent general-relativists working on such problems have been influenced by science fiction. Likewise, science-fiction encounters with alternative cultural features may play an important role in actualizing fundamental social change.

In all the history of the world there has never before been a time in which so many significant changes have occurred. Accommodation to change, the thoughtful pursuit of alternative futures are keys to the survival of civilization and perhaps of the human species. Ours is the first generation that has grown up with science-fiction ideas. I know many young people who will of course be interested but in no way astounded if we receive a message from an extraterrestrial civilization. They have already accommodated to that future. I think it is no exaggeration to say that if we survive, science fiction will have made a vital contribution to the continuation and evolution of our civilization.