According to the popular series Ancient Aliens, on H2 (a spinoff of the History channel), extraterrestrial intelligences visited Earth in the distant past, as evidenced by numerous archaeological artifacts whose scientific explanations prove unsatisfactory for alien enthusiasts. The series is the latest in a genre launched in 1968 by Erich von Däniken, whose book Chariots of the Gods? became an international best seller. It spawned several sequels, including Gods from Outer Space, The Gods Were Astronauts and, just in time for the December 21, 2012, doomsday palooza, Twilight of the Gods: The Mayan Calendar and the Return of the Extraterrestrials (the ones who failed to materialize).
Ancient aliens theory is grounded in a logical fallacy called argumentum ad ignorantiam, or “argument from ignorance.” The illogical reasoning goes like this: if there is no satisfactory terrestrial explanation for, say, the Nazca lines of Peru, the Easter Island statues or the Egyptian pyramids, then the theory that they were built by aliens from outer space must be true.
Whereas the talking heads of Ancient Aliens conjecture that ETs used “acoustic stone levitation” to build the pyramids, for example, archaeologists have discovered images demonstrating how tens of thousands of Egyptian workers employed wood sleds to move the stones along roads from the quarry to the site and then hauled them up gently sloping dirt ramps of an ever growing pyramid. Copper drills, chisels, saws and awls have been found in the rubble around the Great Pyramid of Giza, and the quarries are filled with half-finished blocks and broken tools that show how the Egyptians worked the stone. Conspicuously absent from the archaeological record are any artifacts more advanced than those known to be used in the third millennium B.C.
Written By: Michael Shermercontinue to source article at scientificamerican.com