If we compress the history of the universe into a single year, Earth and our solar system formed around Labor Day, and the development of science occupies no more than the past few seconds. It is extremely unlikely that no other beings would have developed science in the entire “year” before Homo sapiens showed up.
So where are these other civilizations? This question is an expression of what is called the Fermi paradox (named after Enrico Fermi (1901 to 1954), one of the leading physicists of the 20th century).
Given the tendency of natural selection to produce aggressive species—species like Homo sapiens—it is possible that the entire history of the universe has been taken up by the process of evolution producing intelligent life forms on one Goldilocks planet after another, only for those life forms to wipe themselves out once they discover science. In other words, there may have been vast numbers of civilizations that reached our level out there, but they all destroyed themselves before they could colonize their nearby stars. This doomsday scenario is a common explanation for the Fermi paradox.
It’s a chilling thought.
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