Moral enhancement is a topic that has sparked much current interest in the world of bioethics. The possibility of making people ‘better,’ not just in the conventional enhancement sense of improving health and other desirable qualities and capacities, but by making them somehow more moral, more decent, altogether better people, has attracted attention from both advocates 1 2 and sceptics 3 alike. The concept of moral enhancement, however, is fraught with difficult questions, theoretical and practical. What does it actually mean (...) to be ‘more moral’? How would moral enhancement be defined and would it necessarily, as some have claimed, make the world a better or safer place? How would or could such enhancement be achieved safely and without undue constraint on personal liberty and autonomy? On this subject, a recent paper by Crockett et al 4 investigating the effects of the neurotransmitter serotonin on moral decision-making provides an intriguing scientific basis for examining what might or might not constitute moral enhancement. The study involved treatment with citalopram, a drug that increases the action of serotonin in the brain, and subsequent analysis of participants' decision-making behaviour in two different situations involving moral dilemmas: the well-known ‘Trolley Problem’ 5 and the ‘Ultimatum Game’. 6 The researchers found that citalopram promoted what they call ‘prosocial behaviour’, increasing the participants' aversion to causing direct harm to others: in the first scenario, they were less likely to select the option that required killing one in order to save five, and in the second, less likely to reject unfair offers at the expense of others. The Crockett study is fascinating both for its insight into human behaviour and because it appears to demonstrate that, at least on some accounts of moral behaviour, serotonin may in fact be a …. (shrink)

The punishment of criminals is a topic of long-standing philosophical interest since the ancient Greeks. This interest has focused on several considerations, including the justification of punishment, who should be permitted to punish, and how we might best set punishments for crimes. This entry focuses on the most important contributions in this field. The focus will be on specific theoretical approaches to punishment including both traditional theories of punishment (retributivism, deterrence, rehabilitation) and more contemporary alternatives (expressivism, restorative justice, hybrid theories, (...) unified theories) with an additional section on capital punishment, perhaps the particular form of punishment that has received the most sustained philosophical attention. These theories of punishment address two important questions: first, who should be permitted to punish and, secondly, who should be permitted to be punished. These questions then concern the justification of punishment and its distribution. While the majority today often identifies their theories as retributivist, there is a great diversity of theories defended. This entry will highlight the leading work for each view. (shrink)