Consider again the two categories of terrain we recognize when we examine the Moon with the naked eye: the brighter forehead, cheeks and chin, and the darker eyes and mouth. Through a telescope, the bright features are revealed to be ancient cratered highlands, dating back, we now know (from the radioactive dating of samples returned by the Apollo Apollo astronauts), to almost 4.5 billion years ago. The dark features are somewhat younger flows of basaltic lava called maria (singular, mare - both from the Latin word for ocean, although the Moon, we now know, is dry as a bone). The maria welled up in the first few hundred million years of lunar history, partly induced by the high-speed impact of enormous asteroids and comets. The right eye is Mare Imbrium, the beefsteak drooping over the left eye is the combination of Mare Serenitatis and Mare Tranquilitatis (where astronauts), to almost 4.5 billion years ago. The dark features are somewhat younger flows of basaltic lava called maria (singular, mare - both from the Latin word for ocean, although the Moon, we now know, is dry as a bone). The maria welled up in the first few hundred million years of lunar history, partly induced by the high-speed impact of enormous asteroids and comets. The right eye is Mare Imbrium, the beefsteak drooping over the left eye is the combination of Mare Serenitatis and Mare Tranquilitatis (where Apollo 11 Apollo 11 landed), and the off-centre open mouth is Mare Humorum. (No craters can be made out by ordinary, unaided human vision.) landed), and the off-centre open mouth is Mare Humorum. (No craters can be made out by ordinary, unaided human vision.) The Man in the Moon is in fact a record of ancient catastrophes, most of which took place before humans, before mammals, before vertebrates, before multicelled organisms, and probably even before life arose on Earth. It is a characteristic conceit of our species to put a human face on random cosmic violence.

Humans, like other primates, are a gregarious lot. We enjoy one another's company. We're mammals and parental care of the young is essential for the continuance of the hereditary lines. The parent smiles at the child, the child smiles back, and a bond is forged or strengthened. As soon as the infant can see, it recognizes faces, and we now know that this skill is hardwired in our brains. Those infants who a million years ago were unable to recognize a face smiled back less, were less likely to win the hearts of their parents and less likely to prosper. These days, nearly every infant is quick to identify a human face and to respond with a goony grin.

As an inadvertent side effect, the pattern-recognition machinery in our brains is so efficient in extracting a face from a clutter of other detail that we sometimes see faces where there are none. We a.s.semble disconnected patches of light and dark and unconsciously try try to see a face. The Man in the Moon is one result. Michelangelo Antonioni's film to see a face. The Man in the Moon is one result. Michelangelo Antonioni's film Blowup Blowup describes another. There are many other examples. describes another. There are many other examples.

Sometimes it's a geological formation, such as the Old Man of the Mountain at Franconia Notch, New Hampshire. We recognize that, rather than some supernatural agency or an otherwise undiscovered ancient civilization in New Hampshire, this is the product of erosion and collapse of a rock face. Anyway, it doesn't look much like a face anymore. There's the Devil's Head in North Carolina, the Sphinx Rock in Wast Water, c.u.mbria, England, the Old Woman in France, the Vartan Rock in Armenia. Sometimes it's a reclining woman, as Mt Ixtaccihuatl in Mexico. Sometimes it's other body parts, as the Grand Tetons in Wyoming -approached from the West, a pair of mountain peaks named by French explorers. (Actually there are three.) Sometimes it's changing patterns in the clouds. In late medieval and renaissance Spain, visions of the Virgin Mary were 'confirmed' by people seeing saints in cloud forms. (While sailing out of Suva, Fiji, I once saw the head of a truly terrifying monster, jaws agape, set in a brooding storm cloud.) Occasionally, a vegetable or a pattern of wood grain or the hide of a cow resembles a human face. There was a celebrated eggplant that closely resembled Richard M. Nixon. What shall we deduce from this fact? Divine or extraterrestrial intervention? Republican meddling in eggplant genetics? No. We recognize that there are large numbers of eggplants in the world and that, given enough of them, sooner or later we'll come upon one that looks like a human face, even a very particular human face.

When the face is of a religious personage - as, for example, a tortilla purported to exhibit the face of Jesus - believers tend quickly to deduce the hand of G.o.d. In an age more sceptical than most, they crave rea.s.surance. Still, it seems unlikely that a miracle is being worked on so evanescent a medium. Considering how many tortillas have been pounded out since the beginning of the world, it would be surprising if a few didn't have at least vaguely familiar features.*

[* These cases are very different from that of the so-called Shroud of Turin, which shows something too close to a human form to be a misapprehended natural pattern and which is now suggested by carbon-14 dating to be not the death shroud of Jesus, but a pious hoax from the fourteenth century - a time when the manufacture of fraudulent religious relics was a thriving and profitable home handicraft industry.]

Magical properties have been ascribed to ginseng and mandrake roots, in part because of vague resemblances to the human form. Some chestnut shoots show smiling faces. Some corals look like hands. The ear fungus (also unpleasantly called 'Jew's ear') indeed looks like an ear, and something rather like enormous eyes can be seen on the wings of certain moths. Some of this may not be mere coincidence; plants and animals that suggest a face may be less likely to be gobbled up by creatures with faces - or creatures who are afraid of predators with faces. A 'walking stick' is an insect spectacularly well disguised as a twig. Naturally, it tends to live on and around trees. Its mimicry of the plant world saves it from birds and other predators, and is almost certainly the reason that its extraordinary form was slowly moulded by Darwinian natural selection. Such crossings of the boundaries between kingdoms of life are unnerving. A young child viewing a walking stick can easily imagine an army of sticks, branches and trees marching for some ominous planty purpose.

Many instances of this sort are described and ill.u.s.trated in a 1979 book called Natural Likeness Natural Likeness by John Mich.e.l.l, a British enthusiast of the occult. He takes seriously the claims of Richard Shaver, who - as described below - played a role in the origin of the UFO excitement in America. Shaver cut open rocks on his Wisconsin farm and discovered, written in a pictographic language that only he could see, much less understand, a comprehensive history of the world. Mich.e.l.l also accepts at face value the claims of the dramatist and surrealist theoretician Antonin Artaud, who, in part under the influence of peyote, saw in the patterns on the by John Mich.e.l.l, a British enthusiast of the occult. He takes seriously the claims of Richard Shaver, who - as described below - played a role in the origin of the UFO excitement in America. Shaver cut open rocks on his Wisconsin farm and discovered, written in a pictographic language that only he could see, much less understand, a comprehensive history of the world. Mich.e.l.l also accepts at face value the claims of the dramatist and surrealist theoretician Antonin Artaud, who, in part under the influence of peyote, saw in the patterns on the outsides outsides of rocks erotic images, a man being tortured, ferocious animals and the like. 'The whole landscape revealed itself,' Mich.e.l.l says, 'as the creation of a single thought.' But a key question: was that thought inside or outside Artaud's head? Artaud concluded, and Mich.e.l.l agrees, that the patterns so apparent in the rocks were manufactured by an ancient civilization, rather than by Artaud's partly hallucinogen-induced altered state of consciousness. When Artaud returned from Mexico to Europe, he was diagnosed as mad. Mich.e.l.l decries the 'materialist outlook' that greeted Artaud's patterns sceptically. of rocks erotic images, a man being tortured, ferocious animals and the like. 'The whole landscape revealed itself,' Mich.e.l.l says, 'as the creation of a single thought.' But a key question: was that thought inside or outside Artaud's head? Artaud concluded, and Mich.e.l.l agrees, that the patterns so apparent in the rocks were manufactured by an ancient civilization, rather than by Artaud's partly hallucinogen-induced altered state of consciousness. When Artaud returned from Mexico to Europe, he was diagnosed as mad. Mich.e.l.l decries the 'materialist outlook' that greeted Artaud's patterns sceptically.

Mich.e.l.l shows us a photograph of the Sun taken in X-ray light which looks vaguely like a face and informs us that 'followers of Gurdjieff see the face of their Master' in the solar corona. Innumerable faces in trees, mountains and boulders all over the world are inferred to be the product of ancient wisdom. Perhaps some are: it's a good practical joke, as well as a tempting religious symbol, to pile stones so from afar they look like a giant face.

The view that most of these forms are patterns natural to rock-forming processes and the bilateral symmetry of plants and animals, plus a little natural selection - all processed through the human-biased filter of our perception - Mich.e.l.l describes as 'materialism' and a 'nineteenth-century delusion'. 'Conditioned by rationalist beliefs, our view of the world is duller and more confined than nature intended.' By what process he has plumbed the intentions of Nature is not revealed.

Of the images he presents, Mich.e.l.l concludes that their mystery remains essentially untouched, a constant source of wonder, delight and speculation. All we know for sure is that nature created them and at the same time gave us the apparatus to perceive them and minds to appreciate their endless fascination. For the greatest profit and enjoyment they should be viewed as nature intended, with the eye of innocence, unclouded by theories and preconceptions, with the manifold vision, innate in all of us, that enriches and dignifies human life, rather than with the cultivated single vision of the dull and opinionated.

Perhaps the most famous spurious claim of a portentous pattern involves the ca.n.a.ls of Mars. First observed in 1877, they were seemingly confirmed by a succession of dedicated professional astronomers peering through large telescopes all over the world. A network of single and double straight lines was reported, crisscrossing the Martian surface and with such uncanny geometrical regularity that they could only be of intelligent origin. Evocative conclusions were drawn about a parched and dying planet populated by an older and wiser technical civilization dedicated to conservation of water resources. Hundreds of ca.n.a.ls were mapped and named. But, oddly, they avoided showing up on photographs. The human eye, it was suggested, could remember the brief instants of perfect atmospheric transparency, while the undiscriminating photographic plate averaged the few clear with the many blurry moments. Some astronomers saw the ca.n.a.ls. Many did not. Perhaps certain observers were more skilled at seeing ca.n.a.ls. Or perhaps the whole business was some kind of perceptual delusion. Much of the idea of Mars as an abode of life, as well as the prevalence of 'Martians' in popular fiction, derives from the ca.n.a.ls. I myself grew up steeped in this literature, and when I found myself an experimenter on the Manner 9 Manner 9 mission to Mars -the first s.p.a.cecraft to orbit the red planet - naturally I was interested to see what the real circ.u.mstances were. With mission to Mars -the first s.p.a.cecraft to orbit the red planet - naturally I was interested to see what the real circ.u.mstances were. With Mariner 9 Mariner 9 and with and with Viking, Viking, we were able to map the planet pole-to-pole, detecting features hundreds of times smaller than the best that could be seen from Earth. I found, not altogether to my surprise, not a trace of ca.n.a.ls. There were a few more or less linear features that had been made out through the telescope - for example, a 5,000-kilometre-long rift valley that would have been hard to miss. But the hundreds of 'cla.s.sical' ca.n.a.ls carrying water from the polar caps through the arid deserts to the parched equatorial cities simply did not exist. They were an illusion, some malfunction of the human hand-eye-brain combination at the limit of resolution when we peer through an unsteady and turbulent atmosphere. we were able to map the planet pole-to-pole, detecting features hundreds of times smaller than the best that could be seen from Earth. I found, not altogether to my surprise, not a trace of ca.n.a.ls. There were a few more or less linear features that had been made out through the telescope - for example, a 5,000-kilometre-long rift valley that would have been hard to miss. But the hundreds of 'cla.s.sical' ca.n.a.ls carrying water from the polar caps through the arid deserts to the parched equatorial cities simply did not exist. They were an illusion, some malfunction of the human hand-eye-brain combination at the limit of resolution when we peer through an unsteady and turbulent atmosphere.

Even a succession of professional scientists - including famous astronomers who had made other discoveries that are confirmed and now justly celebrated - can make serious, even profound errors in pattern recognition. Especially where the implications of what we think we are seeing seem to be profound, we may not exercise adequate self-discipline and self-criticism. The Martian ca.n.a.l myth const.i.tutes an important cautionary tale.

For the ca.n.a.ls, s.p.a.cecraft missions provided the means of correcting our misapprehensions. But it is also true that some of the most haunting claims of unexpected patterns emerge from from s.p.a.cecraft exploration. In the early 1960s, I urged that we be attentive to the possibility of finding the artefacts of ancient civilizations, either those indigenous to a given worlds or those constructed by visitors from elsewhere. I didn't imagine that this would be easy or probable, and I certainly did not suggest that, on so important a matter, anything short of iron-clad evidence would be worth considering. s.p.a.cecraft exploration. In the early 1960s, I urged that we be attentive to the possibility of finding the artefacts of ancient civilizations, either those indigenous to a given worlds or those constructed by visitors from elsewhere. I didn't imagine that this would be easy or probable, and I certainly did not suggest that, on so important a matter, anything short of iron-clad evidence would be worth considering.

Beginning with John Glenn's evocative report of 'fireflies' surrounding his s.p.a.ce capsule, every time an astronaut reported seeing something not immediately understood, there were those who deduced 'aliens'. Prosaic explanations - specks of paint flecking off the ship in the s.p.a.ce environment, say - were dismissed with contempt. The lure of the marvellous blunts our critical faculties. (As if a man become a moon is not marvel enough.) Around the time of the Apollo Apollo lunar landings, many nonexperts - owners of small telescopes, flying saucer zealots, writers for aeros.p.a.ce magazines - pored over the returned photographs seeking anomalies that NASA scientists and astronauts had overlooked. Soon there were reports of gigantic Latin letters and Arabic numerals inscribed on the lunar surface, pyramids, highways, crosses, glowing UFOs. Bridges were reported on the Moon, radio antennas, the tracks of enormous crawling vehicles, and the devastation left by machines able to slice craters in two. Every one of these claims, though, turns out to be a natural lunar geological formation misjudged by amateur a.n.a.lysts, internal reflections in the optics of the astronauts' Ha.s.selblad cameras, and the like. Some enthusiasts discerned the long shadows of ballistic missiles - Soviet missiles, it was ominously confided, aimed at America. The rockets, also described as 'spires', turn out to be low hills casting long shadows when the Sun is near the lunar horizon. A little trigonometry dispels the mirage. lunar landings, many nonexperts - owners of small telescopes, flying saucer zealots, writers for aeros.p.a.ce magazines - pored over the returned photographs seeking anomalies that NASA scientists and astronauts had overlooked. Soon there were reports of gigantic Latin letters and Arabic numerals inscribed on the lunar surface, pyramids, highways, crosses, glowing UFOs. Bridges were reported on the Moon, radio antennas, the tracks of enormous crawling vehicles, and the devastation left by machines able to slice craters in two. Every one of these claims, though, turns out to be a natural lunar geological formation misjudged by amateur a.n.a.lysts, internal reflections in the optics of the astronauts' Ha.s.selblad cameras, and the like. Some enthusiasts discerned the long shadows of ballistic missiles - Soviet missiles, it was ominously confided, aimed at America. The rockets, also described as 'spires', turn out to be low hills casting long shadows when the Sun is near the lunar horizon. A little trigonometry dispels the mirage.

These experiences also provide fair warning: for a complex terrain sculpted by unfamiliar processes, amateurs (and sometimes even professionals) examining photographs, especially near the limit of resolution, may get into trouble. Their hopes and fears, the excitement of possible discoveries of great import, may overwhelm the usual sceptical and cautious approach of science.

If we examine available surface images of Venus, occasionally a peculiar landform swims into view - as, for example, a rough portrait of Joseph Stalin discovered by American geologists a.n.a.lysing Soviet orbital radar imagery. No one maintains, I gather, that unreconstructed Stalinists had doctored the magnetic tapes, or that the former Soviets were engaged in engineering activities of unprecedented and hitherto unrevealed scale on the surface of Venus - where every s.p.a.cecraft to land has been fried in an hour or two. The odds are overwhelming that this feature, whatever it is, is due to geology. The same is true of what seems to be a portrait of the cartoon character Bugs Bunny on the Uranian moon Ariel. A Hubble s.p.a.ce telescope image of t.i.tan in the near-infrared shows clouds roughly configured to make a world-sized smiling face. Every planetary scientist has a favourite example.

The astronomy of the Milky Way also is replete with imagined likenesses - for example, the Horsehead, Eskimo, Owl, Homunculus, Tarantula and North American Nebulae, all irregular clouds of gas and dust, illuminated by bright stars and each on a scale that dwarfs our solar system. When astronomers mapped the distribution of galaxies out to a few hundred million light years, they found themselves outlining a crude human form which has been called 'the Stickman'. The configuration is understood as something like enormous adjacent soap bubbles, the galaxies formed on the surface of adjacent bubbles and almost no galaxies in the interiors. This makes it quite likely that they will mark out a pattern with bilateral symmetry something like the Stickman.

Mars is much more clement than Venus, although the Viking Viking landers provided no compelling evidence for life. Its terrain is extremely heterogeneous and diverse. With 100,000 or so close-up photographs available, it is not surprising that claims have been made over the years about something unusual on Mars. There is, for example, a cheerful 'happy face' sitting inside a Martian impact crater 8 kilometres (5 miles) across, with a set of radial splash marks outside, making it look like the conventional representation of a smiling Sun. But no one claims that this has been engineered by an advanced (and excessively genial) Martian civilization, perhaps to attract our attention. We recognize that, with objects of all sizes falling out of the sky, with the surface rebounding, slumping and reconfiguring itself after each impact, and with ancient water and mudflows and modern windborne sand sculpting the surface, a wide variety of landforms must be generated. If we scrutinize 100,000 pictures, it's not surprising that occasionally we'll come upon something like a face. With our brains programmed for this from infancy, it would be amazing if we couldn't find one here and there. landers provided no compelling evidence for life. Its terrain is extremely heterogeneous and diverse. With 100,000 or so close-up photographs available, it is not surprising that claims have been made over the years about something unusual on Mars. There is, for example, a cheerful 'happy face' sitting inside a Martian impact crater 8 kilometres (5 miles) across, with a set of radial splash marks outside, making it look like the conventional representation of a smiling Sun. But no one claims that this has been engineered by an advanced (and excessively genial) Martian civilization, perhaps to attract our attention. We recognize that, with objects of all sizes falling out of the sky, with the surface rebounding, slumping and reconfiguring itself after each impact, and with ancient water and mudflows and modern windborne sand sculpting the surface, a wide variety of landforms must be generated. If we scrutinize 100,000 pictures, it's not surprising that occasionally we'll come upon something like a face. With our brains programmed for this from infancy, it would be amazing if we couldn't find one here and there.

A few small mountains on Mars resemble pyramids. In the Elysium high plateau, there is a cl.u.s.ter of them - the biggest a few kilometres across at the base - all oriented in the same direction. There is is something a little eerie about these pyramids in the desert, so reminiscent of the Gizeh plateau in Egypt, and I would love to examine them more closely. Is it reasonable, though, to deduce Martian pharaohs? something a little eerie about these pyramids in the desert, so reminiscent of the Gizeh plateau in Egypt, and I would love to examine them more closely. Is it reasonable, though, to deduce Martian pharaohs?

Similar features are also known on Earth in miniature, especially in Antarctica. Some of them would come up to your knees. If we knew nothing else about them, would it be fair to conclude that they've been manufactured by scale-model Egyptians living in the Antarctic wasteland? (The hypothesis loosely fits the observations, but much else we know about the polar environment and the physiology of humans speaks against it.) They are, in fact, generated by wind erosion - the splatter of fine particles picked up by strong winds blowing mainly in the same direction and, over the years, sculpting what once were irregular hummocks into nicely symmetrical pyramids. They're called dreikanters, dreikanters, from a German word meaning three sides. This is order generated out of chaos by natural processes - something we see over and over again throughout the Universe (in rotating spiral galaxies, for instance). Each time it happens we're tempted to infer the direct intervention of a Maker. from a German word meaning three sides. This is order generated out of chaos by natural processes - something we see over and over again throughout the Universe (in rotating spiral galaxies, for instance). Each time it happens we're tempted to infer the direct intervention of a Maker.

On Mars, there is evidence of winds much fiercer than any ever experienced on Earth, ranging up to half the speed of sound. Planet-wide duststorms are common, carrying fine grains of sand. A steady pitter-patter of particles moving much faster than in the fiercest gales of Earth should, over ages of geological time, work profound changes in rock faces and landforms. It would not be too surprising if a few features - even very large ones - were sculpted by aeolian processes into the pyramidal forms we see.

There is a place on Mars called Cydonia, where a great stone face a kilometre across stares unblinkingly up at the sky. It is an unfriendly face, but one that seems recognizably human. In some representations, it could have been sculpted by Praxiteles. It lies in a landscape where many low hills have been moulded into odd forms, perhaps by some mixture of ancient mudflows and subsequent wind erosion. From the number of impact craters, the surrounding terrain looks to be at least hundreds of millions of years old.

Intermittently, 'The Face' has attracted attention, both in the United States and in the former Soviet Union. The headline in the 20 November 1984 Weekly World News, Weekly World News, a supermarket tabloid not celebrated for its integrity, read: a supermarket tabloid not celebrated for its integrity, read: SOVIET SCIENTIST'S AMAZING CLAIM: RUINED TEMPLES FOUND ON MARS. s.p.a.cE PROBE DISCOVERS REMAINS OF 50,000-YEAR-OLD CIVILIZATION.

The revelations are attributed to an anonymous Soviet source and breathlessly describe discoveries made by a nonexistent Soviet s.p.a.ce vehicle.

But the story of 'The Face' is almost entirely an American one. It was found by one of the Viking Viking orbiters in 1976. There was an unfortunate dismissal of the feature by a project official as a trick of light and shadow, which prompted a later accusation that NASA was covering up the discovery of the millennium. A few engineers, computer specialists and others - some of them contract employees of NASA - worked on their own time digitally to enhance the image. Perhaps they hoped for stunning revelations. That's permissible in science, even encouraged - as long as your standards of evidence are high. Some of them were fairly cautious and deserve to be commended for advancing the subject. Others were less restrained, deducing not only that the Face was a genuine, monumental sculpture of a human being, but claiming to find a city nearby with temples and fortifications.* From spurious arguments, one writer announced that the monuments had a particular astronomical orientation - not now, though, but half a million years ago - from which it followed that the Cydonian wonders were erected in that remote epoch. But then how could the builders have been human? Half a million years ago, our ancestors were busy mastering stone tools and fire. They did not have s.p.a.ceships. orbiters in 1976. There was an unfortunate dismissal of the feature by a project official as a trick of light and shadow, which prompted a later accusation that NASA was covering up the discovery of the millennium. A few engineers, computer specialists and others - some of them contract employees of NASA - worked on their own time digitally to enhance the image. Perhaps they hoped for stunning revelations. That's permissible in science, even encouraged - as long as your standards of evidence are high. Some of them were fairly cautious and deserve to be commended for advancing the subject. Others were less restrained, deducing not only that the Face was a genuine, monumental sculpture of a human being, but claiming to find a city nearby with temples and fortifications.* From spurious arguments, one writer announced that the monuments had a particular astronomical orientation - not now, though, but half a million years ago - from which it followed that the Cydonian wonders were erected in that remote epoch. But then how could the builders have been human? Half a million years ago, our ancestors were busy mastering stone tools and fire. They did not have s.p.a.ceships.

[* The general idea is quite old, going back at least a century to the Martian ca.n.a.l myth of Percival Lowell. As one of many examples, P.E. Cleator, in his 1936 book Rockets Through s.p.a.ce: The Dawn of Interplanetary Travel, Rockets Through s.p.a.ce: The Dawn of Interplanetary Travel, speculated: 'On Mars, the crumbling remains of ancient civilizations may be found, mutely testifying to the one-time glory of a dying world.'] speculated: 'On Mars, the crumbling remains of ancient civilizations may be found, mutely testifying to the one-time glory of a dying world.']

The Martian Face is compared to 'similar faces... constructed in civilizations on Earth. The faces are looking up at the sky because they're looking up to G.o.d.' Or the Face was constructed by the survivors of an interplanetary war that left the surface of Mars (and the Moon) pockmarked and ravaged. What causes all those craters anyway? Is the Face a remnant of a long-extinct human civilization? Were the builders originally from Earth or Mars? Could the Face have been sculpted by interstellar visitors stopping briefly on Mars? Was it left for us to discover? Might they also have come to Earth and initiated life here? Or at least human life? Were they, whoever they were, G.o.ds? Much fervent speculation is evoked.

More recently, claims have been made for a connection between 'monuments' on Mars and 'crop circles' on Earth; of inexhaustible supplies of energy waiting to be extracted from ancient Martian machines; and of a ma.s.sive NASA cover-up to hide the truth from the American public. Such p.r.o.nouncements go far beyond more incautious speculation about enigmatic landforms.

When, in August 1993, the Mars Observer Mars Observer s.p.a.cecraft failed within hailing distance of Mars, there were those who accused NASA of faking the mishap so it could study the Face in detail without having to release the images to the public. (If so, the charade is quite elaborate: all the experts on Martian geomorphol-ogy know nothing about it, and some of us have been working hard to design new missions to Mars less vulnerable to the malfunction that destroyed s.p.a.cecraft failed within hailing distance of Mars, there were those who accused NASA of faking the mishap so it could study the Face in detail without having to release the images to the public. (If so, the charade is quite elaborate: all the experts on Martian geomorphol-ogy know nothing about it, and some of us have been working hard to design new missions to Mars less vulnerable to the malfunction that destroyed Mars Observer.) Mars Observer.) There was even a handful of pickets outside the gates of the Jet Propulsion Laboratory, worked up over this supposed abuse of power. There was even a handful of pickets outside the gates of the Jet Propulsion Laboratory, worked up over this supposed abuse of power.

The tabloid Weekly World News Weekly World News for 14 September 1993 devoted its front page to the headline 'New NASA Photo Proves Humans Lived on Mars!' A fake face, allegedly taken by for 14 September 1993 devoted its front page to the headline 'New NASA Photo Proves Humans Lived on Mars!' A fake face, allegedly taken by Mars Observer Mars Observer in orbit about Mars (in fact, the s.p.a.cecraft seems to have failed before achieving orbit), is said by a non-existent 'leading s.p.a.ce scientist' to prove that Martians colonized Earth 200,000 years ago. The information is being suppressed, he is made to say, to prevent 'world panic'. in orbit about Mars (in fact, the s.p.a.cecraft seems to have failed before achieving orbit), is said by a non-existent 'leading s.p.a.ce scientist' to prove that Martians colonized Earth 200,000 years ago. The information is being suppressed, he is made to say, to prevent 'world panic'.

Put aside the improbability that such a revelation would actually lead to 'world panic'. For anyone who has witnessed a portentous scientific finding in the making - the July 1994 impact of Comet Shoemaker-Levy 9 with Jupiter comes to mind - it will be clear that scientists tend to be effervescent and uncontainable. They have an indomitable compulsion to share new data. Only through prior agreement, not ex post facto, ex post facto, do scientists abide military secrecy. I reject the notion that science is by its nature secretive. Its culture and ethos are, and for very good reason, collective, collaborative and communicative. do scientists abide military secrecy. I reject the notion that science is by its nature secretive. Its culture and ethos are, and for very good reason, collective, collaborative and communicative.

If we restrict ourselves to what is actually known, and ignore the tabloid industry that manufactures epochal discoveries out of thin air, where are we? When we know only a little about the Face, it raises gooseb.u.mps. When we know a little more, the mystery quickly shallows.

Mars has a surface area of almost 150 million square kilometres. Is it so astonishing that one (comparatively) postage-stamp-sized patch in 150 million should look artificial - especially given our penchant, since infancy, for finding faces? When we examine the neighbouring jumble of hillocks, mesas and other complex surface forms, we recognize that the feature is akin to many that do not at all resemble a human face. Why this resemblance? Would the ancient Martian engineers rework only this mesa (well, maybe a few others) and leave all others unimproved by monumental sculpture? Or shall we conclude that other blocky mesas are also sculpted into the form of faces, but weirder faces, unfamiliar to us on Earth?

If we study the original image more carefully, we find that a strategically placed 'nostril' - one that adds much to the impression of a face - is in fact a black dot corresponding to lost data in the radio transmission from Mars to Earth. The best picture of the Face shows one side lit by the Sun, the other in deep shadow. Using the original digital data, we can severely enhance the contrast in the shadows. When we do, we find something rather unfacelike there. The Face is at best half a face. Despite our shortness of breath and the beating of our hearts, the Martian sphinx looks natural - not artificial, not a dead ringer for a human face. It was probably sculpted by slow geological process over millions of years.

But I might be wrong. It's hard to be sure about a world we've seen so little of in extreme close-up. These features merit closer attention with higher resolution. Much more detailed photos of the Face would surely settle issues of symmetry and help resolve the debate between geology and monumental sculpture. Small impact craters found on or near the Face can settle the question of its age. In the case (most unlikely in my view) that the nearby structures were really once a city, that fact should also be obvious on closer examination. Are there broken streets? Crenellations in the 'fort'? Ziggurats, towers, columned temples, monumental statuary, immense frescoes? Or just rocks?

Even if these claims are extremely improbable - as I think they are - they are worth examining. Unlike the UFO phenomenon, we have here the opportunity for a definitive experiment. This kind of hypothesis is falsifiable, a property that brings it well into the scientific arena. I hope that forthcoming American and Russian missions to Mars, especially orbiters with high-resolution television cameras, will make a special effort - among hundreds of other scientific questions - to look much more closely at the pyramids and what some people call the Face and the city.

Even if it becomes plain to everyone that these Martian features are geological and not artificial, monumental faces in s.p.a.ce (and allied wonders) will not, I fear, go away. Already there are supermarket tabloids reporting nearly identical faces seen from Venus to Neptune (floating in the clouds?). The 'findings' are typically attributed to fict.i.tious Russian s.p.a.cecraft and imaginary s.p.a.ce scientists, which of course makes it marginally harder for a sceptic to check the story out.

One of the Mars face enthusiasts now announces: Breakthru News of the Century Censored by NASA for fear of Religious upheavals and breakdowns.

The Discovery of ancient ALIEN RUINS ON THE MOON.

A 'giant city, size of Los Angeles basin, covered by immense gla.s.s dome, abandoned millions of years ago, and shattered by meteors with gigantic tower 5 miles tall, with giant one mile square cube on top' is breathlessly 'CONFIRMED' on the well-studied Moon. The evidence? Photos taken by NASA robotic and Apollo Apollo missions whose significance was suppressed by the government and overlooked by all those lunar scientists in many countries who don't work for the 'government'. missions whose significance was suppressed by the government and overlooked by all those lunar scientists in many countries who don't work for the 'government'.

The 18 August 1992 issue of Weekly World News Weekly World News reports the discovery by 'a secret NASA satellite' of 'thousands maybe even millions of voices' emanating from the black hole at the centre of he galaxy M51, all singing ' "Glory, glory, glory to the Lord on ligh" over and over again'. In English. There is even a tabloid eport, fully although murkily ill.u.s.trated, of a s.p.a.ce probe that )hotographed G.o.d, or at least his eyes and the bridge of his nose, ip there in the Orion Nebula. reports the discovery by 'a secret NASA satellite' of 'thousands maybe even millions of voices' emanating from the black hole at the centre of he galaxy M51, all singing ' "Glory, glory, glory to the Lord on ligh" over and over again'. In English. There is even a tabloid eport, fully although murkily ill.u.s.trated, of a s.p.a.ce probe that )hotographed G.o.d, or at least his eyes and the bridge of his nose, ip there in the Orion Nebula.

The 20 July 1993 WWN WWN sports a banner headline, 'Clinton tfeets with JFK!' along with a faked photo of a plausibly aged, ;lumped-over John Kennedy, having secretly survived the a.s.sa.s.si-lation attempt, in a wheelchair at Camp David. Many pages nside the tabloid, we are informed about another item of possible nterest. In 'Doomsday Asteroids', an alleged top-secret docu-nent quotes alleged 'top' scientists about an alleged asteroid 'M-167') that will allegedly hit the Earth on 11 November 1993 md 'could mean the end of life on Earth'. President Clinton is described as being kept 'constantly informed of the asteroid's josition and speed'. Perhaps it was one of the items he discussed n his meeting with President Kennedy. Somehow, the fact that :he Earth escaped this catastrophe did not merit even a retrospec-:ive paragraph after 11 November 1993 uneventfully pa.s.sed. At east the headline writer's judgement not to burden the front page ivith the news of the end of the world was vindicated. sports a banner headline, 'Clinton tfeets with JFK!' along with a faked photo of a plausibly aged, ;lumped-over John Kennedy, having secretly survived the a.s.sa.s.si-lation attempt, in a wheelchair at Camp David. Many pages nside the tabloid, we are informed about another item of possible nterest. In 'Doomsday Asteroids', an alleged top-secret docu-nent quotes alleged 'top' scientists about an alleged asteroid 'M-167') that will allegedly hit the Earth on 11 November 1993 md 'could mean the end of life on Earth'. President Clinton is described as being kept 'constantly informed of the asteroid's josition and speed'. Perhaps it was one of the items he discussed n his meeting with President Kennedy. Somehow, the fact that :he Earth escaped this catastrophe did not merit even a retrospec-:ive paragraph after 11 November 1993 uneventfully pa.s.sed. At east the headline writer's judgement not to burden the front page ivith the news of the end of the world was vindicated.

Some see this as just a kind of fun. However, we live in a time vhen a real long-term statistical threat of an impact of an asteroid ivith the Earth has been identified. (This real science is of course ihe inspiration, if that's the word, of the WWN WWN story.) Government agencies are studying what to do about it. Stories like this suffuse the subject with apocalyptic exaggeration and whimsy, make it difficult for the public to distinguish real perils from tabloid fiction, and conceivably can impede our ability to take precautionary steps to mitigate the danger. story.) Government agencies are studying what to do about it. Stories like this suffuse the subject with apocalyptic exaggeration and whimsy, make it difficult for the public to distinguish real perils from tabloid fiction, and conceivably can impede our ability to take precautionary steps to mitigate the danger.

The tabloids are often sued - sometimes by actors and actresses who stoutly deny they have performed loathsome acts - and large sums of money occasionally change hands. The tabloids must consider such suits as just one of the costs of doing a very profitable business. In their defence they often say that they are at the mercy of their writers and have no inst.i.tutional responsibility to check out the truth of what they publish. Sal Ivone, the managing editor of Weekly World News, Weekly World News, discussing the stories he publishes, says 'For all I know, they could be the product of active imaginations. But because we're a tabloid, we don't have to question ourselves out of a story.' Scepticism doesn't sell newspapers. Writers who have defected from the tabloids describe 'creative' sessions in which writers and editors dream up stories and headlines out of whole cloth, the more outrageous the better. discussing the stories he publishes, says 'For all I know, they could be the product of active imaginations. But because we're a tabloid, we don't have to question ourselves out of a story.' Scepticism doesn't sell newspapers. Writers who have defected from the tabloids describe 'creative' sessions in which writers and editors dream up stories and headlines out of whole cloth, the more outrageous the better.

Out of their immense readership, are there not many who take the stories at face value, who believe the tabloids 'couldn't' print it if it wasn't so? Some readers I talk to insist they read them only for entertainment, just as they watch 'wrestling' on television, that they're not in the least taken in, that the tabloids are understood by publisher and reader alike to be whimsies that explore the absurd. They merely exist outside any universe burdened by rules of evidence. But my mail suggests that large numbers of Americans take the tabloids very seriously indeed.

In the 1990s the tabloid universe is expanding, voraciously gobbling up other media. Newspapers, magazines or television programmes that labour under prissy restraints imposed by what is actually known are outsold by media outlets with less scrupulous standards. We can see this in the new generation of acknowledged tabloid television, and increasingly in what pa.s.ses for news and information programmes.

Such reports persist and proliferate because they sell. And they sell, I think, because there are so many of us who want so badly to be jolted out of our humdrum lives, to rekindle that sense of wonder we remember from childhood, and also, for a few of the stories, to be able, really and truly, to believe in Someone older, smarter and wiser who is looking out for us. Faith is clearly not enough for many people. They crave hard evidence, scientific proof. They long for the scientific seal of approval, but are unwilling to put up with the rigorous standards of evidence that impart credibility to that seal. What a relief it would be: doubt reliably abolished! Then, the irksome burden of looking after ourselves would be lifted. We're worried - and for good reason -about what it means for the human future if we have only ourselves to rely upon.

These are the modern miracles, shamelessly vouched for by those who make them up from scratch, bypa.s.sing any formal sceptical scrutiny, and available at low cost in every supermarket, grocery store and convenience outlet in the land. One of the pretences of the tabloids is to make science, the very instrument of our disbelief, confirm our ancient faiths and effect a convergence of pseudoscience and pseudoreligion.

By and large, scientists' minds are open when exploring new worlds. If we knew beforehand what we'd find, it would be unnecessary to go. In future missions to Mars or to the other fascinating worlds in our neck of the cosmic woods, surprises -even some of mythic proportions - are possible, maybe even likely. But we humans have a talent for deceiving ourselves. Scepticism must be a component of the explorer's toolkit, or we will lose our way. There are wonders enough out there without our inventing any.

4.

Aliens

Truly, that which makes me believe there is no inhabitant on this sphere, is that it seems to me that no sensible being would be willing to live here.'

'Well, then!' said Micromegas, 'perhaps the beings that inhabit it do not possess good sense.'

One alien to another, on approaching the Earth, in Voltaire's Micromegas: Micromegas: A Philosophical History (1752) (1752)

It's still dark out. You're lying in bed, fully awake. You discover you're utterly paralysed. You sense someone in the room. You try to cry out. You cannot. Several small grey beings, less than four feet tall, are standing at the foot of the bed. Their heads are pear-shaped, bald, and large for their bodies. Their eyes are enormous, their faces expressionless and identical. They wear tunics and boots. You hope this is only a dream. But as nearly as you can tell it's really happening. They lift you up and, eerily, they and you slip through the wall of your bedroom. You float out into the air. You rise high toward a metallic saucer-shaped s.p.a.cecraft. Once inside, you are escorted into a medical examining room. A larger but similar being, evidently some kind of physician, takes over. What follows is even more terrifying. Your body is probed with instruments and machines, especially your s.e.xual parts. If you're a man, they may take sperm samples; if you're a woman, they may remove ova or foetuses, or implant s.e.m.e.n. They may force you to have s.e.x. Afterwards you may be ushered into a different room where hybrid babies or foetuses, partly human and partly like these creatures, stare back at you. You may be given an admonition about human misbehaviour, especially in despoiling the environment or in allowing the AIDS pandemic; tableaux of future devastation are offered. Finally, these cheerless grey emissaries escort you out of the s.p.a.cecraft and ooze you back through the walls into your bed. By the time you're able to move and talk... they're gone.

You may not remember the incident right away. Instead you might simply find some period of time unaccountably missing, and puzzle over it. Because all this seems so weird, you're a little concerned about your sanity. Naturally you're reluctant to talk about it. At the same time the experience is so disturbing that it's hard to keep it bottled up. It all pours out when you hear of similar accounts, or when you're under hypnosis with a sympathetic therapist, or even when you see a picture of an 'alien' in one of the many popular magazines, books, and TV 'specials' on UFOs. Some people say they can recall such experiences from early childhood. Their own children, they think, are now being abducted by aliens. It runs in families. It's a eugenics programme, they say, to improve the human breeding stock. Maybe aliens have always done this. Maybe, some say, that's where humans came from in the first place.

As revealed by repeated polls over the years, most Americans believe that we're being visited by extraterrestrial beings in UFOs. In a 1992 Roper opinion poll of nearly 6,000 American adults -especially commissioned by those who accept the alien abduction story at face value - 18 per cent reported sometimes waking up paralysed, aware of one or more strange beings in the room. About 13 per cent reported odd episodes of missing time, and 10 per cent claimed to have flown through the air without mechanical a.s.sistance. From nothing more than these results, the poll's sponsors conclude that two per cent of all Americans have been abducted, many repeatedly, by beings from other worlds. The question of whether respondents had been abducted by aliens was never actually put to them.

If we believed the conclusion drawn by those who bankrolled and interpreted the results of this poll, and if aliens are not partial to Americans, then the number for the whole planet would be more than a hundred million people. This means an abduction every few seconds over the past few decades. It's surprising more of the neighbours haven't noticed.

What's going on here? When you talk with self-described abductees, most seem very sincere, although caught in the grip of powerful emotions. Some psychiatrists who've examined them say they find no more evidence of psychopathology in them than in the rest of us. Why should anyone claim to have been abducted by alien creatures if it never happened? Could all these people be mistaken, or lying, or hallucinating the same (or a similar) story? Or is it arrogant and contemptuous even to question the good sense of so many?

On the other hand, could there really be a ma.s.sive alien invasion; repugnant medical procedures performed on millions of innocent men, women and children; humans apparently used as breeding stock over many decades and all this not generally known and dealt with by responsible media, physicians, scientists and the governments sworn to protect the lives and well-being of their citizens? Or, as many have suggested, is there a ma.s.sive government conspiracy to keep the citizens from the truth?

Why should beings so advanced in physics and engineering crossing vast interstellar distances, walking like ghosts through walls be so backward when it comes to biology? Why, if the aliens are trying to do their business in secret, wouldn't they perfectly expunge all memories of the abductions? Too hard for them to do? Why are the examining instruments macroscopic and so reminiscent of what can be found at the neighbourhood medical clinic? Why go to all the trouble of repeated s.e.xual encounters between aliens and humans? Why not steal a few egg and sperm cells, read the full genetic code, and then manufacture as many copies as you like with whatever genetic variations happen to suit your fancy? Even we humans, who as yet cannot quickly cross interstellar s.p.a.ce or slither through walls, are able to clone cells.

How could humans be the result of an alien breeding programme if we share 99.6 per cent of our active genes with the chimpanzees? We're more closely related to chimps than rats are to mice. The preoccupation with reproduction in these accounts raises a warning flag, especially considering the uneasy balance between s.e.xual impulse and societal repression that has always characterized the human condition, and the fact that we live in a time fraught with numerous ghastly accounts, both true and false, of childhood s.e.xual abuse.

Contrary to many media reports,* the Roper pollsters and those who wrote the 'official' report never asked whether their subjects had been abducted by aliens. They deduced deduced it: those who've ever awakened with strange presences around them, who've ever unaccountably seemed to fly through the air, and so on, have therefore been abducted. The pollsters didn't even check to see if sensing presences, flying etc. were part of the same or separate incidents. Their conclusion that millions of Americans have been so abducted is spurious, based on careless experimental design. it: those who've ever awakened with strange presences around them, who've ever unaccountably seemed to fly through the air, and so on, have therefore been abducted. The pollsters didn't even check to see if sensing presences, flying etc. were part of the same or separate incidents. Their conclusion that millions of Americans have been so abducted is spurious, based on careless experimental design.

[* For example, the 4 September 1994 Publisher's Weekly: Publisher's Weekly: 'According to a Gallup [sic] poll, more than three million Americans believe they have been abducted by aliens.'] 'According to a Gallup [sic] poll, more than three million Americans believe they have been abducted by aliens.']

Still, at least hundreds of people, perhaps thousands, claiming they have been abducted, have sought out sympathetic therapists or joined abductee support groups. Others may have similar complaints but, fearing ridicule or the stigma of mental illness, have refrained from speaking up or getting help.

Some abductees are also said to be reluctant to talk for fear of hostility and rejection by hardline sceptics (although many willingly appear on radio and TV talk shows). Their diffidence supposedly extends even to audiences that already believe in alien abductions. But maybe there's another reason: might the subjects themselves be unsure at least at first, at least before many retellings of their story whether it was an external event they are remembering or a state of mind?

'One unerring mark of the love of truth,' wrote John Locke in 1690, 'is not entertaining any proposition with greater a.s.surance than the proofs it is built upon will warrant.' On the matter of UFOs, how strong are the proofs?

The phrase 'flying saucer' was coined when I was entering high school. The newspapers were full of stories about ships from beyond in the skies of Earth. It seemed pretty believable to me. There were lots of other stars, at least some of which probably had planetary systems like ours. Many stars were as old or older than the Sun, so there was plenty of time for intelligent life to evolve. Caltech's Jet Propulsion Laboratory had just flown a two-stage rocket high above the Earth. Clearly we were on our way to the Moon and the planets. Why shouldn't other, older, wiser beings be able to travel from their star to ours? Why not?

This was only a few years after the bombing of Hiroshima and Nagasaki. Maybe the UFO occupants were worried about us, and sought to help us. Or maybe they wanted to make sure that we and our nuclear weapons didn't come and bother them. them. Many people seemed to see flying saucers - sober pillars of the community, police officers, commercial airplane pilots, military personnel. And apart from some harumphs and giggles, I couldn't find any counterarguments. How could all these eyewitnesses be mistaken? What's more, the saucers had been picked up on radar, and pictures had been taken of them. You could see the photos in newspapers and glossy magazines. There were even reports about crashed flying saucers and little alien bodies with perfect teeth stiffly languishing in Air Force freezers in the southwest. Many people seemed to see flying saucers - sober pillars of the community, police officers, commercial airplane pilots, military personnel. And apart from some harumphs and giggles, I couldn't find any counterarguments. How could all these eyewitnesses be mistaken? What's more, the saucers had been picked up on radar, and pictures had been taken of them. You could see the photos in newspapers and glossy magazines. There were even reports about crashed flying saucers and little alien bodies with perfect teeth stiffly languishing in Air Force freezers in the southwest.

The prevailing climate was summarized in Life Life magazine a few years later, in these words: 'These objects cannot be explained by present science as natural phenomena - but solely as artificial devices, created and operated by a high intelligence.' Nothing 'known or projected on Earth could account for the performance of these devices.' magazine a few years later, in these words: 'These objects cannot be explained by present science as natural phenomena - but solely as artificial devices, created and operated by a high intelligence.' Nothing 'known or projected on Earth could account for the performance of these devices.'

And yet not a single adult I knew was preoccupied with UFOs. I couldn't figure out why not. Instead they were worried about Communist China, nuclear weapons, McCarthyism and the rent. I wondered if they had their priorities straight.

In college, in the early 1950s, I began to learn a little about how science works, the secrets of its great success, how rigorous the standards of evidence must be if we are really to know something is true, how many false starts and dead ends have plagued human thinking, how our biases can colour our interpretation of the evidence, and how often belief systems widely held and supported by the political, religious and academic hierarchies turn out to be not just slightly in error, but grotesquely wrong.

I came upon a book called Extraordinary Popular Delusions and the Madness of Crowds Extraordinary Popular Delusions and the Madness of Crowds written by Charles Mackay in 1841 and still in print. In it could be found the histories of boom-and-bust economic crazes, including the Mississippi and South Sea 'Bubbles' and the extravagant run on Dutch tulips, scams that bamboozled the wealthy and t.i.tled of many nations; a legion of alchemists, including the poignant tale of Mr Kelly and Dr Dee (and Dee's 8-year-old son Arthur, impressed by his desperate father into communicating with the spirit world by peering into a crystal); dolorous accounts of unfulfilled prophecy, divination and fortune-telling; the persecution of witches; haunted houses; 'popular admiration of great thieves'; and much else. Entertainingly portrayed was the Count of St Germain, who dined out on the cheerful pretension that he was centuries old if not actually immortal. (When, at dinner, incredulity was expressed at his recounting of his conversations with Richard the Lion-Heart, he turned to his man-servant for confirmation. 'You forget, sir,' was the reply, 'I have been only five hundred years in your service.' 'Ah, true,' said St Germain, 'it was a little before your time.') written by Charles Mackay in 1841 and still in print. In it could be found the histories of boom-and-bust economic crazes, including the Mississippi and South Sea 'Bubbles' and the extravagant run on Dutch tulips, scams that bamboozled the wealthy and t.i.tled of many nations; a legion of alchemists, including the poignant tale of Mr Kelly and Dr Dee (and Dee's 8-year-old son Arthur, impressed by his desperate father into communicating with the spirit world by peering into a crystal); dolorous accounts of unfulfilled prophecy, divination and fortune-telling; the persecution of witches; haunted houses; 'popular admiration of great thieves'; and much else. Entertainingly portrayed was the Count of St Germain, who dined out on the cheerful pretension that he was centuries old if not actually immortal. (When, at dinner, incredulity was expressed at his recounting of his conversations with Richard the Lion-Heart, he turned to his man-servant for confirmation. 'You forget, sir,' was the reply, 'I have been only five hundred years in your service.' 'Ah, true,' said St Germain, 'it was a little before your time.') A riveting chapter on the Crusades began Every age has its peculiar folly; some scheme, project, or phantasy into which it plunges, spurred on either by the love of gain, the necessity of excitement, or the mere force of imitation. Failing in these, it has some madness, to which it is goaded by political or religious causes, or both combined.

The edition I first read was adorned by a quote from the financier and adviser of Presidents, Bernard M. Baruch, attesting that reading Mackay had saved him millions.

There had been a long history of spurious claims that magnetism could cure disease. Paracelsus, for example, used a magnet to suck diseases out of the human body and dispose of them into the Earth. But the key figure was Franz Mesmer. I had vaguely understood the word 'mesmerize' to mean something like hypnotize. But my first real knowledge of Mesmer came from Mackay. The Viennese physician had thought that the positions of the planets influenced human health, and was caught up in the wonders of electricity and magnetism. He catered to the declining French n.o.bility on the eve of the Revolution. They crowded into a darkened room. Dressed in a gold-flowered silk robe and waving an ivory wand, Mesmer seated his marks around a vat of dilute sulphuric acid. The Magnetizer and his young male a.s.sistants peered deeply into the eyes of their patients, and rubbed their bodies. They grasped iron bars protruding into the solution or held each other's hands. In contagious frenzy, aristocrats -especially young women - were cured left and right.

Mesmer became a sensation. He called it 'animal magnetism'. For the more conventional medical pract.i.tioner, though, this was bad for business, so French physicians pressured King Louis XVI to crack down. Mesmer, they said, was a menace to public health. A commission was appointed by the French Academy of Sciences that included the pioneering chemist Antoine Lavoisier, and the American diplomat and expert on electricity, Benjamin Franklin. They performed the obvious control experiment: when the. magnetizing effects were performed without the patient's knowledge, no cures were effected. The cures, if any, the commission concluded, were all in the mind of the beholder. Mesmer and his followers were undeterred. One of them later urged the following att.i.tude of mind for best results: Forget for a while all of your knowledge of physics... Remove from your mind all objections that may occur... Never reason for six weeks ... Be very credulous; be very persevering; reject all past experience, and do not listen to reason.

Oh, yes, a final piece of advice: 'Never magnetize before inquisitive persons.' Another eye-opener was Martin Gardner's Fads and Fallacies in the Name of Science. Fads and Fallacies in the Name of Science. Here was Wilhelm Reich uncovering the key to the structure of galaxies in the energy of the human o.r.g.a.s.m; Andrew Crosse creating microscopic insects electrically from salts; Hans Horbiger under n.a.z.i aegis announcing that the Milky Way was made not of stars, but of s...o...b..a.l.l.s; Charles Piazzi Smyth discovering in the dimensions of the Great Pyramid of Gizeh a world chronology from the Creation to the Second Coming; L. Ron Hubbard writing a ma.n.u.script able to drive its readers insane (was it ever proofed? I wondered); the Bridey Murphy case, which led millions into concluding that at last there was serious evidence of reincarnation; Joseph Rhine's 'demonstrations' of ESP; appendicitis cured by cold water enemas, bacterial diseases by bra.s.s cylinders, and gonorrhoea by green light - and amid all these accounts of self-deception and charlatanry, to my surprise a chapter on UFOs. Here was Wilhelm Reich uncovering the key to the structure of galaxies in the energy of the human o.r.g.a.s.m; Andrew Crosse creating microscopic insects electrically from salts; Hans Horbiger under n.a.z.i aegis announcing that the Milky Way was made not of stars, but of s...o...b..a.l.l.s; Charles Piazzi Smyth discovering in the dimensions of the Great Pyramid of Gizeh a world chronology from the Creation to the Second Coming; L. Ron Hubbard writing a ma.n.u.script able to drive its readers insane (was it ever proofed? I wondered); the Bridey Murphy case, which led millions into concluding that at last there was serious evidence of reincarnation; Joseph Rhine's 'demonstrations' of ESP; appendicitis cured by cold water enemas, bacterial diseases by bra.s.s cylinders, and gonorrhoea by green light - and amid all these accounts of self-deception and charlatanry, to my surprise a chapter on UFOs.

Of course, merely by writing books cataloguing spurious beliefs, Mackay and Gardner came across, at least a little, as grumpy and superior. Was there nothing they accepted? Still, it was stunning how many pa.s.sionately argued and defended claims to knowledge had amounted to nothing. It slowly dawned on me that, human fallibility being what it is, there might be other explanations for flying saucers.

I had been interested in the possibility of extraterrestrial life from childhood, from long before I ever heard of flying saucers. I've remained fascinated long after my early enthusiasm for UFOs waned - as I understood more about that remorseless taskmaster called the scientific method: everything hinges on the matter of evidence. On so important a question, the evidence must be airtight. The more we want it to be true, the more careful we have to be. No witness's say-so is good enough. People make mistakes. People play practical jokes. People stretch the truth for money or attention or fame. People occasionally misunderstand what they're seeing. People sometimes even see things that aren't there.