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Some time ago I spoke with a young man who had personally customized his pickup truck to produce 450 horsepower and an illegal cloud of black diesel smoke each time he pressed the accelerator. He had fathered several young children, and I asked whether air pollution from belching machines like his truck threatened their health. His response: “God doesn’t intend the world to last forever.”
Walking under New Mexico big skies, I put his dismissal of human-caused damage to Earth’s life support systems together with the “Fermi Paradox.” Physicist Enrico Fermi observed the contradiction between (1) what science tells us is the high probability of life elsewhere among the Milky Way Galaxy’s 200-400 billion suns and the tendency of life to develop intelligence, and (2) the fact that we have no evidence of extraterrestrial technology. Dr Carl Sagan estimated in 1966 that there is intelligent life on as many as one million planets in the Milky Way, and the federal government and others have launched and continued an aggressive, but apparently unsuccessful, Search for Extraterrestrial Intelligence (SETI).
Why are we not hearing the equivalent of extraterrestrial radio’s Top 40 tunes? Dr. Sagan suggested that intelligent life using technology detectable from Earth might be very rare, because civilizations invariably destroy themselves within a century or so after developing radio or space flight technology.
I prefer a more optimistic hypothesis: there is lots of intelligence out there in civilizations which have survived a dangerous adolescence where run-away technology threatened the civilation’s destruction. The survivors moved on to a post-technology adulthood, to mature civilizations where intelligent life exists in harmony with the extraterrestrial planet’s natural limits.
So my answer to the young man is that our world, with mankind, is going to survive; we just need to figure out how to get beyond your poisonous truck and the technology that supports it. My secular alternative to his divine time limit is a suggestion that the universe does not permit high-technology, high-consumption civilizations to continue for long. Civilizations with unsustainable habits, such as our own, change their ways or they go away.