An anonymous reader writes: Oxytocin is a shy molecule – the brain must be coaxed into making it – and then it disappears rapidly, with a three-minute half-life. So, how can we measure virtues? Rather than asking people if they were moral (who would say no?), researchers tempted subjects with virtue and vice by putting a stack of money in front of them. If they trusted a stranger with their money, the money would grow, but then the stranger may or may not be trustworthy and share the largess with them.
By taking blood from participants, researchers showed that the more money people received showing trust, the more their brains produced oxytocin. And, the more oxytocin in their systems, the more money they reciprocated to the person who had initially trusted them.