One of the media’s most astute observers of bioethical trends is William Saletan, chief national correspondent of the web magazine Slate. He recently surveyed a growing belief amongst neuroscientists that the source of morality is not God or transcendent reason but the brain. We are, so to speak, hard-wired to think morally. For instance, three years ago, a paper in the journal Neuron argued that morality reflects "an underlying tension between competing subsystems in the brain".

A recent study in Nature supports this view. If your ventromedial prefrontal cortex, the site responsible for emotion, is damaged, people become abnormally utilitarian in their moral calculations. The scientists conclude that their research can test whether "different philosophies are compatible with human nature". As Saletan observes, the translation of this is that "brain science has discredited religion and philosophy".

Whether or not this is philosophically true, scientists are hard at work learning how to tweak brains so that we can be good utilitarians whose thought processes are not contaminated with messy emotions. "Right now, we’re discovering the seat of morality," warns Zack Lynch, of the Neurotechnology Industry Organization. "In 10 to 15 years, we’ll have the technologies to manipulate it."