Many of us think human extinction would be a very bad thing, and that we have moral reasons to prevent it. But there is disagreement over what would make extinction so bad, and thus over what grounds these moral reasons. Recently, several theorists have argued that our reasons to prevent extinction stem not just from the value of the welfare of future lives, but also from certain additional values relating to the existence of humanity itself (for example, humanity's “final” value, or the value of humanity in itself). In this paper, I argue against these “additional value” views. Despite their initial appeal, these views will inevitably face conflicts between the additional values to which they appeal, and the value of the welfare of future lives. And, I argue, the views cannot plausibly resolve these conflicts. In contrast, these conflicts do not arise for a rival view, on which our reasons to prevent extinction stem just from the value of the welfare of future lives. I conclude that this gives us reason to prefer the latter view, despite the greater initial plausibility of additional value views.

中文翻译：

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为什么要阻止人类灭绝？

我们许多人认为人类灭绝是一件非常糟糕的事情，我们有道德理由阻止它。但对于什么会使灭绝变得如此严重，以及这些道德理由的依据，存在分歧。最近，一些理论家认为，我们防止灭绝的原因不仅源于未来生命的福利价值，还源于某些附加值与人类本身的存在有关（例如，人类的“最终”价值，或人类本身的价值）。在本文中，我反对这些“附加价值”观点。尽管它们最初很有吸引力，但这些观点将不可避免地面临它们所诉诸的附加价值与未来生活福利价值之间的冲突。而且，我认为这些观点无法合理地解决这些冲突。相比之下，这些冲突并不是因为对立的观点而产生的，在这种观点上，我们防止灭绝的理由仅仅源于来世福利的价值。我的结论是，这使我们有理由选择后一种观点，尽管附加价值观点最初似乎更合理。