Broca's Brain by Carl Sagan

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 astronomicaltradition 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