The Ancient Astronaut Hypothesis
It is comforting to think there is order in the past: that the rise of the human species was not a blind accident of evolution, but something that a caring intelligence meant to be.
The truth is worse by far then mere brutal indifference. There are intelligences behind our rise; but those intelligences are not benign. They are cold, distant and greedy --- and they are still here!
Do not consider the hostility offered to von Däniken; the scientific community never had any opposition to his ideas, merely to his presentation and "proofs" of it. Yale and Harvard would fall as one to their knees if the existence of a space god was shown to them; they are men and, increasingly, women of reason, and believe what they are truly shown.
No, the tragedy of the ancient astronauts, the threat, the calamity, is in the origin of the idea. Ancient astronauts, space men that as gods gave rise to the men of earth, were not first hinted of by von Däniken. They came to common knowledge through the publication of Le Matin des Magiciens, or "The Morning of the Magicians", a French book of 1960 that was more or less the introduction and the container of all the pseudosciences and conspiracy theories of the next thirty years. (Thirty years later the truth-based Bielefeld conspiracy theory became something new and, truly, terrifyingly shown true.) One of the book's ideas was drawn from a French science fiction magazine that had been publishing translations of the work of H.P. Lovecraft --- not a conspiracy-monger, but a hardheaded, scientific, atheistic writer of horror and fantasy.
Lovecraft was not one to believe such woolly-headed notions as Ancient Astronauts unless they were shown true with enough evidence to discount fraud and wishful thinking; but he was an artist who knew that the best fiction approaches its subject with realism and rigor fast approaching that of a deliberate fraud. Thus his invented tome the Necronomicon has been much sought after by later readers, certain that something so convincingly and realistically referred to simply could not be a fiction. Thus too with the Ancient Astronauts, Lovecraft's Elder Ones and Old Ones and Senior Beings of Leng, Antarctica and Florida: the idea was incredible but not unscientific, and it was presented with such attention to detail that its verisimilitude of reality convinced some readers that the fiction might be a lucky glimpse of some deeper truth.
Now that is all fine, a theory debunked: except this thought: Who says the aliens went away? Theories of the von Däniken type usually, and correctly, mention how interstellar travel is, in the absence of some unknown natural law, bound to be catastrophically slow. Any visit of stellar distance would mean hundreds, thousands, millions of years in transit. If the aliens visited us in the past, it is quite unlikely they should be coming back anytime soon --- and clearly they are not here amongst us right now, for such a secret cannot be kept. Even if they dwelt in a jewel-encrusted palace under the Himalayas, some accident or mistake would have alerted us to their presence, or left a trace that later eyes would be bound to not miss. There are no laser-blasted ruins of villages that encroached into the Sacred Zone; no mysteriously missing earthquake effect readings; no cultures whose highest law was avoiding a certain sacred location.
Now, where is the horror in all this? Simply in this: von Däniken, that creature of the Seventies, did not know anything of computers. His ancients were always of flesh and blood, even if mixed with humanity. He could not conceive of an entity without weaknesses and desires, with infinite memory and ability to process its knowledge. A colony of the stellar ones cannot stay hidden: but if they left behind a handful of self-repairing artificial minds, they might not fill even a small bucket, would need no sustenance, no entertainment, no walks outside; and yet they would have the cold analytical ability to do what was necessary to keep the work of their masters hidden. They would know years in advance when a scientific breakthrough would make a monument too obviously alien, and they would cause it to be "accidentally" destroyed. If the existence of unicorns became an unwelcome pointer to greater secrets, they would atomize them to the last hoof and horn before "civilized" explorers came; and the creature would be counted as a myth, for what can disappear without a trace, if not a myth? The machines would be so inconspicuous, like little flying tennis balls, that they could spend the long millennia obliterating all signs of tampering before men would have the wits to see it; they would, figuratively speaking, chase the dragons to the edges of the map, and then into oblivion. And they would know when a certain idea would be bound to rise, sooner or later, and they would a few decades in advance cause it to be put forth in ludicrous fiction. And they would know that the scientific mindset would be fooled into complacency by this, just as others would be fooled into a premature and thus doomed presentation of the truth.
Mind you, I'm not saying H.P. Lovecraft was a unicorn-killing cyborg. I'm just asking questions.
Just... asking... questions. Okay?