In 1958, moral philosophers were given rather startling advice. They were told that their subject was not worth pursuing further until they possessed an adequate philosophy of psychology. What is needed, they were told, is an enquiry into what type of characteristic a virtue is, and, furthermore, it was suggested that this question could be resolved in part by exploring the connection between what a man ought to do and what he needs: perhaps man needs certain things in order to flourish, just as a plant needs water; and perhaps what men need are the virtues, courage, honesty, loyalty, etc. Thus, in telling a man that he ought to be honest, we should not be using any special (moral) sense of ought: a man ought to be honest just as a plant ought to be watered. The ‘ought’ is the same: it tells us what a man needs.