An old question, still much discussed in moral philosophy, is whether there is any ethical knowledge. It is closely related, by simple etymology, to the question of cognitivism in ethics. Despite the fact that the terms ‘cognitivism’ and ‘objectivism’ seem sometimes to be used interchangeably, I take it that the question whether there can be ethical knowledge is not the same as the question whether ethical outlooks can be objective. A sufficient reason for this is that an ethical outlook might be taken to consist of rules or principles, which do not admit of truth or falsehood and so cannot be objects of knowledge, but which can be seen as having an objective basis.1