The Varieties of Scientific Experience: A Personal View of the Search for God

by Carl Sagan

  Von Daniken noted that in Peru, in the plains of Nazca, there are large drawings on the desert that can properly be seen only from a great altitude. And they depict nothing very extraordinary in themselves: turkeys, condors, and other natural beasts and vegetables. But von Daniken wonders why anyone would construct something that could be seen only from a great altitude, from which he deduces not only that there were beings at a great altitude to see it but that such beings directed the construction, saying, "A little to the left." Now, in American football games, it is customary for people to be outfitted each with a square of cardboard on which is the fragment of a line or a letter. And at the appropriate moment, everybody holds up their piece, and from a great distance some symbol generally having to do with the hope for success of the home team is displayed. And yet no one deduces extraterrestrial intervention in such a case.

  Or, von Daniken noted that in the Pacific, on Easter Island, there is a set of massive stone monoliths all facing to the sea, all of which are much too heavy to be lifted by one or two people and all of which, as Jacob Bronowski mentioned, look exactly like Benito Mussolini. They were quarried some substantial distance away on this very small island. And again von Daniken deduces extraterrestrial manufacture from the fact that he cannot himself figure out how people living before the industrial revolution could cut, transport, and erect these monoliths. And yet years before von Daniken wrote, Thor Heyerdahl had gone to Easter Island and with a small team using only the simplest of tools, had transported and erected one of these monoliths that had been found in a supine position. And the erection method included just shoving small bits of dirt and stone under one side of it until it got to the high, steeper angle and then finally stood up.

  So there are many other such arguments by von Daniken, most of which have lower plausibility than the arguments I've just presented to you. I've presented some of his best cases. Fundamentally what von Daniken has done is to sell our ancestors short, to assume that people who lived a few thousand years ago or even a few hundred years ago were simply too stupid to figure anything out, certainly to work together for a long period of time to construct something of monumental dimensions. And yet people of a few hundred or a few thousand years ago were no less intelligent than we are, no less able. Perhaps in some ways they were better able to work together. The argument is absurdly specious. So how do we understand that so specious an argument could have been so wildly successful (although today one does not hear much about ancient astronauts)? It's an interesting question.

  I think the answer is absolutely clear. The emotional appeal of von Daniken made perfect sense. It was the hope that extraterrestrials would come and save us from ourselves. The hope that if they had intervened many times in human history, surely in the present time, a time of great crisis recognized in the 1960s and '70s and manifestly clear today in an age of fifty-five thousand nuclear weapons, that the extraterrestrials would come and prevent us from doing the worst to ourselves. And in that sense I consider it an extremely dangerous doctrine, because the more likely we are to assume that the solution comes from the outside, the less likely we are to solve our problems ourselves.

  But ancient astronauts are only a sideshow, a minor codicil of the principal doctrine along these lines of the twentieth century, and that is flying saucers or unidentified flying objects. And here we have not just the writings of a half dozen people but some collective enterprise involving an enormous number of people all over the world, and something like 1 million separate sightings since 1947, when the term "flying saucer" was first coined.

  The standard mythos is quite straightforward. It's that a device of exotic design and manufacture is seen in the sky, at least sometimes doing things that no machine of terrestrial manufacture could do. More rarely, it discharges exotic beings, who engage in conversations with terrestrials, capturing people from the Earth, performing exotic medical examinations on them, taking them to other planets, and occasionally having sexual congress with them, resulting in offspring who are fully human-a feat somewhat less likely, if we bear in mind the clear evidence of Darwinian evolution, than the successful mating between a man and a petunia.

  Now, what would we require, if we took even a modestly skeptical approach, to be convinced? We would not require a million cases. I don't think we would require more than one, provided that one case were absolutely solid. We would require that that solid case be simultaneously very reliably reported and very exotic. It is insufficient to have several hundred people see it independently as a light in the sky. A light in the sky can be anything. It has to be much more concrete, much more specific. On the other hand, it is also insufficient to have, let us say, a twenty-meter-diameter, saucer-shaped, metallic object land in a suburban garden on Long Island, a seamless door open (there is some fascination with seamless doors in these stories), a four-meter-high robot walk out, pet the cat, pick a flower, wave to the startled householder, and then disappear back into the seamless door, which closes, and the craft takes off. If only one person saw it, the cat being unavailable for corroboratory testimony, then this likewise is not a compelling case. We would require that the examples be, simultaneously, extremely reliably reported and extremely exotic.

  I have spent, although not recently, a great deal of time on UFO cases, feeling that it was my responsibility, since I'm interested in extraterrestrial life, to see if the problem has not been finessed, if the extraterrestrials are not here, in which case, of course, my colleagues and I would be saved a great deal of effort. I spent time on a committee established by the U.S. Air Force to look into this story and have interviewed some of the participants in a few of the most famous cases. And let me give you my overall impressions.

  By no means are all UFO cases identified, established as to what they are. Some of them are too sparsely and scantily reported, and a few are sufficiently mysterious, so of course you couldn't expect that to be the case.

  But let me give you a sense of routine UFO reports that have been checked out and we do know what they are:

  The Moon. You may think that there is no way that someone could identify the Moon as an extraterrestrial spacecraft. But there are many cases where not only has that been done but the Moon has been reported as following and even harassing the observer.

  The aurora borealis; bright stars; bright planets, especially under unconventional meteorological conditions; flights of luminescent insects; a low overcast, an automobile going up a hill, the headlights moving rapidly across the overcast; weather balloons.

  There was a famous case in which a firefly was trapped between two adjacent panes of glass in an airplane cockpit window and the pilots were radioing about fantastic right-angle turns, defying the laws of inertia, estimated fantastic speeds.

  They imagined it at some huge distance away instead of right in front of their noses.

  Noctilucent and lenticular clouds, lens-shaped clouds, conventional aircraft with unconventional lighting. Unconventional aircraft.

  Then there is a vast category of hoaxes. As soon as you could get your name in the newspaper by reporting a UFO, a lot more people started seeing UFOs than had done so previously. And some of them were done in good fun, some not. A famous case was a set of plastic bags from dry cleaners that were fashioned to form a hood around candles and the whole business sent aloft to make a small hot-air balloon, which can be done. And this very primitive technology was reported by hundreds of people as UFOs and performing maneuvers that, it was claimed, could not possibly have been performed. So there's a hoax plus some misapprehensions or flawed reporting, and the net result is something extraordinarily exotic. But it was only strange moving lights. This is one of the reasons I say that merely moving lights are insufficient.

  Then there are cases of so-called high evidence. Photographs, for example. One of the earliest photographs of UFOs from the late 1940s was from a man named George Adamski, who was a space enthusiast and, in fact, identified himself in his first book as George Adamski of Mount Pal
omar. Mount Palo-mar was then the site of the largest optical telescope on the planet. And George Adamski was from Mount Palomar. He owned a hamburger stand at the base of Mount Palomar, in which he had a small telescope, and through that telescope he photographed wonders that the astronomers, consigned to the lofty recesses of the mountain, never saw.

  One of his most famous photographs shows a clearly metallic, saucer-shaped object with three large spheres at the bottom, which he identified as landing gear and which later turned out to be a chicken brooder suspended by thread. This is one of those devices that encourages the eggs to hatch, and ordinary light-bulbs are used to warm it. And indeed there developed an entire detective industry to determine what common object was being photographed close up to explain this particular unidentified flying object case.

  Now, I've probably made the point implicitly, but let me make it explicitly. I do not think there is any fundamental difference between this sort of UFO hoaxmongering and the sale of relics in the Middle Ages-pieces of the true cross and so on. The motivations are almost identical.

  There are also cases, and Adamski was one of them, where people not only photograph or see UFOs but are hailed by the occupants and taken aboard. Some of these cases are useful to examine in retrospect. For example, Adamski was taken to the planet Venus, where conditions were very much like those in Eden. The extraterrestrials spoke mellifluously, walked among rivulets and flowers, wore long white robes, and gave heartening religious homilies.

  We know now, as we did not know then, that the surface temperature of Venus is nine hundred degrees Fahrenheit. The surface pressures are ninety times what they are in this room. The atmosphere contains hydrochloric acid, hydrofluoric acid, and sulfuric acid. So at the very least, the long white robes would have been in tatters. We can in retrospect see that there must have been something wrong with the story. Maybe he just got the planet wrong. But one is left with the distinct impression that Adamski's account was contrived out of whole cloth.

  It is remarkable that in all these million cases there is not one example of physical evidence that sustains even the most casual scrutiny. No pieces of spacecraft chipped off with a penknife and put into an envelope and carried back for laboratory examination of exotic alloys. No photograph of the interior of the spacecraft or the extraterrestrials, or a page from the captain's logbook. Somehow, in all of these cases, there is not a single example of concrete physical evidence. And that again is suggestive, I maintain, that we are dealing with some combination of psychopathology and conscious fraud and the misapprehension of natural phenomena, but not what is alleged by those who see UFOs.

  I'd like to give you a specific case, because I think it's an example of how people with the best intentions in the world can nevertheless be badly fooled. Sometime in the 1950s, a highway patrolman in New Mexico is driving along a rural road that he knows extremely well, having driven along that road many many times. And, to his astonishment, he sees a large, saucer-shaped object just settling down on the ground, the sunlight glinting off it. He's astonished. He pulls off to the side of the road and examines it. He then drives some tens of meters away to an emergency telephone at the side of the road and gets patched in to some scientists he happens to know at Los Alamos National Laboratory. He tells them, "The most extraordinary thing has just happened to me. This is a once-in-a-lifetime opportunity. I have just seen a flying saucer land. It is within my sight now. I have not had anything to drink. I am fully awake. I am in full possession of my senses. And if you get out here right away with monitoring equipment, we have the find of the century."

  This scene is so compelling that the scientists are able to commandeer a helicopter and fly to the site. They land on the highway, approach the policeman-and, sure enough, in front of them is just what he described. Saucer-shaped, metallic, large, gleaming in the Sun. So, carrying their equipment, they rush toward it, and as they approach, they notice a farmer who is doing his farming things, totally oblivious to this large saucer that has just landed in front of him. They start thinking, is it possible that the saucer is invisible to the farmer but visible to them? Maybe the farmer has been hypnotized. They approach. The farmer finally sees them, if not the flying saucer, and challenges them. Why are they trespassing on his land? They say, "Because of the saucer." "Saucer? What saucer?" He turns around and looks exactly at it and apparently does not see it. Well, it turns out, after some few minutes of confused discussion, that what they were seeing was a silo for the storage of grain that the farmer was using, that he had himself made from-I've forgotten now from what, but it was indeed saucer-shaped-that he had been using for years.

  Everything the highway patrolman had seen was right, except for one small detail. He had the impression that he had just seen it land, and he had not. Everything else was exactly as told. And what this stresses is that in an argument of this sort every link in the chain of argument has to be right. It's not enough for most links in the chain to be right. If you have one weak link, the entire chain of argument can collapse.

  Now, it is sometimes said that people who take a skeptical approach to UFOs or ancient astronauts or indeed some varieties of revealed religion are engaging in prejudice. I maintain this is not prejudice. It is postjudice. That is, not a judgment made before examining the evidence but a judgment made after examining the evidence.

  It does not say that as you finish reading this you will not walk outside and come upon a metallic flying saucer sitting there, posing embarrassment to the author. I would gladly trade my embarrassment for a genuine contact with an extraterrestrial civilization. But I maintain that after we have a certain amount of experience with such cases, an overall trend becomes clear, and that is that in cases of this sort we are enormously vulnerable to misunderstanding, to misevaluating. What we are talking about is not significantly different from what is called a miracle.

  The definitive work on miracles was written by a famous Scottish philosopher, David Hume. In his book An Inquiry Concerning Human Understanding, in a famous chapter called "Of Miracles," Hume is considering a slightly but not very significantly different case.

  When anyone tells me that he saw a dead man restored to life, I immediately consider with myself whether it be more probable that this person should either deceive or be deceived or that the fact which he relates should really have happened. I weigh the one miracle against the other and according to the superiority which I discover, I pronounce my decision. Always I reject the greater miracle. If the falsehood of his testimony would be more miraculous than the event which he relates, then and not till then, can he pretend to command my belief or opinion.

  And another way in which this has been phrased is by Thomas Paine, one of the heroes of the American Revolution, who is essentially paraphrasing Hume. He says, "Is it more probable that nature should go out of her course or that a man should tell a lie?"

  What is being said here is that mere eyewitness testimony is insufficient if what is being reported is sufficiently extraordinary. Paine goes on to say,

  We have never seen, in our time, nature go out of her course. But we have good reason to believe that millions of lies have been told in the same time. It is therefore at least millions to one that the reporter of a miracle tells a lie.

  Strong stuff.

  Without a doubt it is more interesting if miracles occur than if they do not. It makes a better story. And I can recall a case that happened to me. I was at a restaurant nearby Harvard University. Suddenly the proprietor and most of the diners rushed outside, napkins still tucked under their belts. My attention was attracted. I rushed outside also and saw a very strange light in the sky. I lived not far away, walked home (without paying the bill, but I told the proprietor I would return), got a pair of binoculars, came back, and with the binoculars was able to see that the one light was actually divided into two lights, that exterior to the two lights were a red light and a green light. The red light and the green light were blinking, and it was, it later turned out, a massive
weather airplane with two powerful searchlights to determine the turbidity of the atmosphere. I told the people at the restaurant what I had seen. Everyone was uniformly disappointed. I asked why. And everyone had the same answer. It is a memorable story to go home and say, "I just saw a spaceship from another planet hovering over Harvard Square." It is a highly nonmemorable story to go home and say, "I saw an airplane with a bright light."

  But beyond that, miracles speak to us of all sorts of things religious that we have powerful wishes to believe. This is true to such an extent that people become very angry when miracles are debunked. One of the most interesting cases of this sort- and there are thousands of them-is within the Roman Catholic Church, where there is an established procedure for verifying alleged miracles. It's in fact where the phrase "devil's advocate" comes from. The devil's advocate is the person who proposes alternative explanations of the alleged miracle, to see how good the evidence is. I have in front of me a newspaper clipping from June a year ago, titled "Priests Denounced After Rejecting Miracle Claim." And let me just read a few sentences:

  Stockton, California. Angry believers denounced a panel of priests as "a bunch of devils" after the clergymen ruled that a weeping Madonna in a rural Roman Catholic church is probably a hoax, not a miracle. One woman, Lavergne Pita, burst into tears when the findings were announced Wednesday by the Diocese of Stockton. Manuel Pita protested that "these investigators are not investigators. They're a bunch of devils. How can they do this?" Reports that the sixty-pound statue sheds real tears and can move as far as thirty feet from its niche in Mater Ecclesiae Mission Church in Thornton began circulating two years ago. Church attendance has tripled since then… Last year the diocese named a commission to study the reports. In announcing the panel's finding, Bishop Roger M. Mahoney said the events connected with the statue "do not meet the criteria for an authenticated appearance of Mary, the mother of Jesus Christ." The statue may have been moved, the tears may have been applied… Actually, the tears were never reported to flow, they were just seen, and they were gluey. One of the proponents said, "When the virgin appeared to the kids in Portugal, they didn't believe them either. These things usually happen to the humble and low incomes. The poor," he added. "These things are not for everyone."