• General
• enhancement
• moral enhancement
• behaviour

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 (and desired) qualities and capacities, but by making them somehow more moral, more decent, altogether better people, has attracted attention from both advocates1 2 and sceptics3 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 al4 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 (though not moral behaviour per se) and because it appears to demonstrate that, at least on some accounts of moral behaviour, serotonin may in fact be a …