Broca's Brain: The Romance of Science

by Carl Sagan

  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.