Even if we think the prior existence view is more plausible than the total view, we should recognize that we could be mistaken about this and therefore give some value to the life of a possible future—let’s say, for example, 10 per cent of the value we give to the similar life of a presently existing being. The number of human beings who will come into existence only if we can avoid extinction is so huge that even with that relatively low value, reducing the risk of human extinction will often be a highly cost-effective strategy for maximizing utility, as long as we have some understanding of what will reduce that risk.

Katarzyna de Lazari-Radek & Peter Singer, The Point of View of the Universe: Sidgwick and Contemporary Ethics, Oxford, 2014, pp. 376-377