The world after
Derek Parfit · Reasons and Persons · 1984
Two policies lie open to us. One spares resources; the other uses them up for immediate comfort and will leave, three centuries hence, an impoverished world. But there is a subtlety: depending on the policy chosen, daily life, jobs and migrations will differ, so that different couples will meet and different children will be born. The people who will inhabit the impoverished world thus owe it their very existence: under the other policy they would never have been born, and others would live in their place. Their lives, though harder, are worth living. Can we then say we have harmed them, since none of them is worse off than they would otherwise have been?
Our choices impoverish the future world, but also decide who will be born into it. Those people would not exist without us: are we wronging them?