There is a branch of philosophy that does precisely this. It thinks about how to value those kinds of lives, population ethics. This can sound very abstract, but of course there are examples all around us. Any time a family is considering whether to have a child, that act will create another person. Should the government pay for fertility treatment a couple might require? That turns that rather intimate question into a question of public policy.
Cows are venerated in India, but precisely how intensely often depends on politics. And being venerated does not necessarily yield a pleasant life for the creatures. Economists rarely consider how policies will affect birth rates and the yet-to-be-born; we examine the thorny topic of “population ethics”. And foreign-language phrasebooks may be in decline but they maintain huge historical value.
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