What We Owe the Future, by William MacAskill

What We Owe the Future: A Million-Year View (2022)

MacAskill argues that future people count morally, that there will be vastly more of them than there are of us, and that the long-run consequences of present action should therefore dominate the calculation. It originates the logic of longtermism and the thinking of civilizational existential risk. It is also the moral arithmetic that turns optimization into a duty, which is exactly the move my book is written against — not because the concern for the future is wrong, but because of who ends up holding the microphone.

Read it asking: if trillions of unborn people have a claim on today's decisions, who holds their proxy, and who selected them? Berlin's warning about positive liberty was that someone else gets to define your real interests. Longtermism performs that operation on people who cannot yet object.