It is comforting to one embroiled in the tantalising, and not infrequently exasperating prolegomena to Christian philosophy, to be able to make an assertion which is unlikely to be controverted by anyone familiar with recent theological writing. The assertion is to the effect that two concepts which have been much to the fore of late are ‘communication’ and ‘relevance’. Christians are urged from all sides to find ways of communicating with present-day, secularised, ‘post-Christian’ man, in such a way that he will see the relevance of their gospel. Indeed, the challenge has been put so often that one can readily see the point of Professor J. McIntyre's suspicion that relevance seems to be replacing truth as a criterion of permissible discourse; and one can echo his sigh, ‘Sometimes I think that I would appreciate an address that claimed unashamedly to be “irrelevant”.’ What concerns us is the possibility that certain efforts in the direction of communication and relevance merit the charge of reductionism, that is, the charge that in some way the distinctives of the Christian message are being watered down or undermined. No doubt reductionism may take many forms, but it is that variety of the phenomenon which might be termed ‘logical reductionism’, which more immediately concerns us.