“Assuming that the observable universe is void of extraterrestrial civilizations, then what hangs in the balance is at least 1e22 [10 with 21 zeros] human lives (though the true number is probably larger). If we represent all the happiness experienced during one entire such life with a single teardrop of joy, then the happiness of these souls could fill and refill the Earth’s oceans every second, and keep doing so for a hundred billion billion millennia. It is really important that we make sure these truly are tears of joy.”

— Nick Bostrom

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