(for 3 Quarks Daily)
I’m not sold on longtermism myself, but its proponents sure have my sympathy for the eagerness with which its opponents mine their arguments for repugnant conclusions. The basic idea, that we ought to do more for the benefit of future lives than we are doing now, is often seen as either ridiculous or dangerous.
Usually, this takes the form of thought-experiments in which longtermists are supposed to accept major harm to humanity now in the hope of some huge potential benefit later. Physicist and YouTuber Sabine Hossenfelder, after boasting that she couldn’t be bothered to read William MacAskill’s book What We Owe the Future (“because if the future thinks I owe it, I’ll wait until it sends an invoice”), goes on to interpret a paper by MacAskill and his colleague Hilary Greaves in this way: “a few million deaths are acceptable, so long as we don’t go extinct.” Phil Torres takes aim at an updated version of the same paper, in which Greaves and MacAskill argue that possible futures with huge numbers of people, even if they are unlikely, represent an expected value that outweighs that of the near future. He reads it as implying that MacAskill and Greaves might well press a button that lets 1 million people die now, to increase the chance that 100 trillion people will be born later.
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