Some things, people say, are “gone forever.” But what exactly does that mean? At a minimum, it suggests that certain losses are final in the sense that they are irreversible. Such losses are irreparable in the sense that nothing can be done to restore the status quo ante—or if something can be done, it is not enough (or perhaps outsiders can never know if it is). The experience of grief is usually produced by a sense not only that the loss is large, but also that it cannot be reversed. Consider some examples. If children are killed, they cannot be brought back to life. If a soldier loses the use of his leg, he cannot grow it back. If a species is lost, it is probably lost forever; the same might well be true of pristine areas. Some people fear that genetically modified organisms might lead to irreversible ecological harm; transgenic crops can impose irreversible losses by increasing pest resistance. In recent decades, the problem of climate change has raised serious concerns about irreversibility. Some greenhouse gases stay in the atmosphere for centuries, and for that reason climate change threatens to be irreversible, at least for all practical purposes. And, of course, genocide may be the most extreme case of irreversible harm.

中文翻译：

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作为不可逆性的不可修复性

人们说，有些事情“一去不复返了”。但这究竟是什么意思？至少，它表明某些损失是最终的，因为它们是不可逆转的。从某种意义上说，这种损失是无法弥补的，因为无法采取任何措施来恢复原状——或者如果能做一些事情，这还不够（或者外人永远无法知道是否足够）。悲伤的体验通常是由一种感觉产生，不仅损失很大，而且无法逆转。考虑一些例子。如果儿童被杀害，他们将无法复活。如果一个士兵失去了他的腿的使用，他就不能再长出来。如果一个物种消失了，它很可能永远消失了；原始地区很可能也是如此。有些人担心转基因生物可能会导致不可逆转的生态危害；转基因作物可以通过增加害虫抗性来造成不可逆转的损失。近几十年来，气候变化问题引起了人们对不可逆转性的严重关切。一些温室气体在大气中停留了几个世纪，因此气候变化有不可逆转的威胁，至少对于所有实际目的而言是这样。而且，当然，种族灭绝可能是不可逆转伤害的最极端案例。