Published online by Cambridge University Press: 24 October 2008
In this century the major insight in the field of moral philosophy has been that moral arguments need not proceed by way of the deduction of moral conclusions from non-moral premises. This realisation sprang from a recognition that the purpose of moral argument was not just to get one party to a moral disagreement to assent to a proposition that at the outset of the discussion he denied. If a moral argument was to be able to be considered successful it was insufficient for someone to recognise that an action he had previously considered right was wrong; it was essential that this recognition have an influence on his subsequent conduct. The change in belief was important only in so far as it led to a change in action. And although this insight led people to over diminish the importance of belief and propose various types of non-cognitive theories of ethics, it is none the less true that the acceptance of a proposition of the form ‘action X is wrong’ must have an impact of some kind on the behaviour of those who accept it.