Hello!
This is from the article about the Titan Prometheus @ the Wikipedia:
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Before his theft of fire, Prometheus played a decisive role in the Titanomachy, securing victory for Zeus and the other Olympians. Zeus's torture of Prometheus thus becomes a particularly harsh betrayal. The scope and character of Prometheus' transgressions against Zeus are also widened. In addition to giving humankind fire, Prometheus claims to have taught them the arts of civilization, such as writing, mathematics, agriculture, medicine, and science. The Titan's greatest benefaction for humankind seems to have been saving them from complete destruction. In an apparent twist on the myth of the so-called Five Ages of Man found in Hesiod's Works and Days (wherein Cronus and, later, Zeus created and destroyed five successive races of mortal men), Prometheus asserts that Zeus had wanted to obliterate the human race, but that he somehow stopped him.
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Maybe ...:
David=Prometheus (after all, he is Inmortal as only a robot can be, just like the Titans were)
Space Jockey´s race=Gods (they created worlds through terraforming, and biological beings/human races through biotech)
Present Humans in the movie=Humankind V6.0 (V1.0 through V5.0 already obsolete)
Space Jockey´s ampule biotech goo=Fire
Maybe Ridley read this same article @Wikipedia when completing the script.