Imagining a future world in which people no longer die provides a helpful tool for understanding our present ethical views. It becomes evident that the cardinal virtues of prudence, temperance, and courage are options for reasonable people rather than rational requirements. On the assumption that the medical means to immortality are not universally available, even justice becomes detached from theories that tie the supposed virtue to the protection of human rights. Several stratagems are available for defending a categorical right to life under these circumstances, but none is compelling. Justice and human rights should therefore be understood as social conventions whose stability depends upon rejecting a tyranny of the immortals in favour of cultural traditions that connect rights and liberties with the means for their enjoyment.

Epistemic duties would be duties to believe, disbelieve, or withhold judgement from propositions, and they would be grounded in purely evidential considerations. I offer a new argument for the claim that there are no epistemic duties. Though people may have duties to believe, disbelieve, or withhold judgement from propositions, those duties are never grounded in purely epistemic considerations. Rather, allegedly epistemic duties are a species of moral duty.

A popular response to proponents of embryonic stem cell research and advocates of abortion rights alike—summarized by claims such as “you came from an embryo!” or “you were a fetus once!”—enjoys a rich philosophical pedigree in the arguments of Hare, Marquis, and others. According to such arguments from potentiality, the prenatal human organism is morally valuable because every person's biological history depends on having completed embryonic and fetal stages. In this article I set out the steps of the underlying argument in light of how it has been cast in the philosophical literature and uncover an intriguingly illicit inference.