Derek Parfit famously opined that causing a person to exist with a life barely worth living can be wrong, although it is not wrong for that person. This conundrum is known as the nonidentity problem. Parfit also held that persons can, in a morally relevant sense, be caused to exist in the distant future by actions that make the agent a necessary condition for a person’s existence. When these views are combined, which he did, and applied explicitly to persons with a life not worth living, which he did not, an interesting conditional conclusion can be drawn. If every family line eventually produces a person with a life not worth living, and if causing that person to exist cannot be justified by the benefits befalling others in the family line, it is always wrong to have children. Parfit did not draw this antinatalist conclusion, but an analysis of his introduction of the nonidentity problem shows that he could have. Since Parfit’s other views on population ethics continue to be discussed with relative respect, it stands to reason that the antinatalist position should be no exception. Right or wrong, it has its legitimate place in considerations concerning the future of reproduction.

This paper explores what could be wrong with the fact of human extinction. I first present four reasons why we might consider human extinction to be wrong: (1) it would prevent millions of people from being born; (2) it would mean the loss of rational life and civilization; (3) it would cause existing people to suffer pain or death; (4) it would involve various psychological traumas. I argue that looking at the question from a contractualist perspective, only reasons (3) and (4) are admissible. I then consider what implications this limitation on reasons has for the wrongfulness of various forms of human extinction.

In the Anthropocene, human beings are capable of bringing about globally catastrophic outcomes that could damage conditions for present and future human life on Earth in unprecedented ways. This paper argues that the scale and severity of these dangers justifies a new international criminal offence of ‘postericide’ that would protect present and future people against wrongfully created dangers of near extinction. Postericide is committed by intentional or reckless systematic conduct that is fit to bring about near human extinction. The paper argues that a proper understanding of the moral imperatives embodied in international criminal law shows that it ought to be expanded to incorporate a new law of postericide.

Thomas Nagel in ‘The Absurd’ (Nagel 1971) mentions the future expunction of the human species as a ‘metaphor’ for our ability to see our lives from the outside, which he claims is one source of our sense of life's absurdity. I argue that the future expunction (not to be confused with extinction) of everything human – indeed of everything biological in a terran sense – is not a mere metaphor but a physical certainty under the laws of nature. The causal processes by which human expunction will take place are presented in some empirical detail, so that philosophers cannot dismiss it as merely speculative. I also argue that appeals to anthropic principles or to forms of mystical cosmology are of no plausible avail in the face of human expunction under the laws of physics.