Your birth rank might be a clue to how close humanity is to extinction

The Doomsday Argument reasons that you're more likely to be born somewhere in the middle of the total number of humans who will ever live than extremely near the beginning. If roughly 100 billion people have been born so far, that logic suggests the total number of humans ever born probably isn't vastly larger, which would put humanity's end sooner than we might assume. Physicist Brandon Carter and philosopher John Leslie developed the argument, and it remains contested.

— John Leslie, The End of the World: A Scientific and Ethical Analysis — 1996
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