On person-affecting views in population ethics, the moral import of a person’s welfare depends on that person’s temporal or modal status. These views typically imply that – all else equal – we’re never required to create extra people, or to act in ways that increase the probability of extra people coming into existence. -/- In this paper, I use Parfit-style fission cases to construct a dilemma for person-affecting views: either they forfeit their seeming-advantages and face fission analogues of the problems (...) faced by their rival impersonal views, or else they turn out to be not so person-affecting after all. In light of this dilemma, the attractions of person-affecting views largely evaporate. What remains are the problems unique to them. (shrink)

It may soon be possible for neurotechnology to connect two subjects' brains such that they share a single token mental state, such as a feeling of pleasure or displeasure. How will our moral frameworks have to adapt to accommodate this prospect? And if this sort of mental-state-sharing might already obtain in some cases, how should this possibility impact our moral thinking? This question turns out to be extremely challenging, because different examples generate different intuitions: If two subjects share very few (...) mental states, then it seems that we should count the value of those states twice, but if they share very many mental states, then it seems that we should count the value of those statesonce. We suggest that these conflicting intuitions can be reconciled if the mental states that matter for welfare have a holistic character, in a way that is independently plausible. We close by drawing tentative conclusions about how we ought to think about the moral significance of shared mental states. (shrink)

According to the cohabitation account, all the persons that result from a fission event cohabit the same body prior to fission. This article concerns a problem for this account. Suppose Manuel and Jimena are suffering from an equally painful migraine. Unlike Jimena, however, Manuel will undergo fission. Assuming you have a spare painkiller, whom should you give it to? Intuitively, you have no more reason to give it to one or the other. The problem is that the cohabitation account suggests (...) otherwise. According to the account, there are two persons cohabiting Manuel’s body, in which case you should arguably give them the pill, since doing so alleviates the pain of more beings. One response argues that the two persons cohabiting Manuel’s body share one pain. Thus, giving them the pill alleviates no more pain than giving it to Jimena, and therefore you have no more reason to do one or the other. The goal of this article is to show that this response fails. (shrink)

According to the cohabitation account, all the persons that result from a fission event cohabit the same body prior to fission. This article concerns a problem for this account. Suppose Manuel and Jimena are suffering from an equally painful migraine. Unlike Jimena, however, Manuel will undergo fission. Assuming you have a spare painkiller, whom should you give it to? Intuitively, you have no more reason to give it to one or the other. The problem is that the cohabitation account suggests (...) otherwise. According to the account, there are two persons cohabiting Manuel’s body, in which case you should arguably give them the pill, since doing so alleviates the pain of more beings. One response argues that the two persons cohabiting Manuel’s body share one pain. Thus, giving them the pill alleviates no more pain than giving it to Jimena, and therefore you have no more reason to do one or the other. The goal of this article is to show that this response fails. (shrink)

Nozick’s ‘utility monster’ is often regarded as impossible, because one life cannot be better than a large number of other lives. Against that view, I propose a purely marginalist account of utility monster defining the monster by a higher sensitivity of well-being to resources (instead of a larger total well-being), and I introduce the concept of collective utility monster to account for resource predation by a group. Since longevity strengthens the sensitivity of well-being to resources, large groups of long-lived persons (...) may, if their longevity advantage is sufficiently strong, fall under the concept of collective utility monster, against moral intuition. (shrink)