In his book Obedience to Authority, Stanley Milgram presents the results of some psychological experiments that suggest the extent to which people from a wide range of walks of life are prepared to act in a way that is contrary to their conscience, simply because they are obeying authority. In chapter 2, he makes the following point (1974, p. 13): ‘of all moral principles, the one that comes closest to being universally accepted is this: one should not inflict suffering on a helpless person who is neither harmful nor threatening to oneself’. Yet the cases he describes are instances where many people, none of them particularly sadistic or violent by nature, are prepared to inflict pain on others.