Ethics of procreation: Consider a scientist that could grow humans knowing that two thirds of them would die after suffering short lives of terror and extreme deprivation, but one third of the lives he could produce in this manner would survive to a productive adult life. We would think that if he were to create extremely bad lives rather than good lives, he would be committing Mengalian atrocities, or at least, that is what I think the general intuition would be. But there are conditions in which people procreate knowing that their children will suffer short and extremely bad lives, in subsistence conditions, where two thirds of the children they produce will suffer in this way. To ensure the two cases are analogous, suppose that the scientist creates these lives only to ensure his genetic continuation, his security in old age, or out of economic necessity, and will stop producing lives only when he has two viable children to support him and work in his lab. Can one context of procreation be plausibly justified without this justification extending to the case of the scientist, which I assume nobody believes may be justified? If so, how? Is there anything about the natural context of sexual procreation that serves to justify what would ordinarily be beyond excuse?

Based on your description of the scenarios you're envisioning, I'm not seeing any inherent moral difference between the scientist and those who procreate children in the 'ordinary' or 'natural' way. Whatever moral reasons seem to weigh either for or against procreating children knowing that there is a high probability they will have "short and extremely bad lives" apply equally to the scientist as to anyone else who procreates under the same conditions. Perhaps you're seeking to highlight that the scientist 'grows' humans outside of a "natural context" as a morally significant factor that makes his procreative acts morally worse. There I'd have to say that while his creating the offspring in some sort of artificial or 'unnatural' way adds to the 'ick' factor, but it's hard to see how there's any moral difference there.

No doubt many people attach some moral significance to 'naturalness' when it comes to procreation. They might argue that somehow natural procreation isn't subject to the same moral standards that other procreative acts are. But again, I don't see any rational basis for that view. Put differently: It's difficult to see how procreating naturally rather than artificially can make otherwise morally objectionable procreative acts morally unobjectionable.

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