I would like to try and clarify the relation between language, philosophy and science. This is a matter, over which there has been a great deal of confusion even among scientists and philosophers. Since the subject is vast, I propose to treat it in very general terms, pointing out some places of special difficulty, and indicating, in broad terms, where I believe the source of the difficulties lie. This will lead to a general statement of attitude to these matters that it is hoped will be capable of reapplication to all other aspects of the relationship. I am in a sense resorting to a process of 'showing', since this is a field where proof, in the ordinary sense, has little obvious place. Let us first remind ourselves that there are often many ways of answering the same question. When asked why the lights went out, we can reply in terms of the throwing of a switch, or we can explain in greater detail how the switch breaks a continuous electrical circuit, or we can go further, and discuss the nature of electricity and Quantum theory. All of these alternatives constitute a sensible answer to the question, but they differ greatly in their degree of complexity. Similarly they may differ in their choice of technical terms, thus I may draw my terminology from either engineering or biology, even though I am explaining the same phenomenon. Perhaps the most common sort of distinction between explanations is that which explains on one hand by reference to private experience, and that which explains by reference to public experience. It is this sort of difference, ff real in some sense, that I wish to discuss as part of my problem, although there must be an immediate doubt as to whether