498 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS problems, do no come carefully labelled 'attention Physics Department' or whatever. The environmental influences are those of the society in which we live. And these find expression through a multitude of channels. Consumerism is not just something which Ralph Nader and 'Which' do outside our lives, we are all consumers and while moodily grumbling about the need to put on the shampoo label the number of cc (or is it ml?), nevertheless we would be the first to complain if the whisky or tomato juice were short measure. In a democratic society, these pressures should be translated into the law of the land--which ultimately rests on consent. And the law, national or supranational, provides another enviromental influence. The corporate company environment in which the evaluation scientist operates is of the utmost importance. The far-reaching consequences of his efforts may be fully understood, vaguely appreciated or even opposed. He may be seen as a philosophic leader or an exploited technician, but in either case he will probably be hard-worked. So one would expect Evaluation Science to have made dramatic ad- vances since the S.C.C. was founded in 1948. And it has. The first general use of the term seems to be around the mid-1950s. But in any case it is a newcomer compared to the disciplines encompassed by the previous Medal Lectures: Biochemistry, Organic Chemistry, Physics, Dermatology and Medicine. Needless to say that this recognition delights me. What is this thing we call Evaluation Science ? Essentially it is a measure- ment science, but within boundaries very different from those of metrology. It subsumes not only measurement of physical parameters and chemical analysis but also physiological and even psychological quantification it makes great call on statistics not just as a science but as a philosophy. It operates in a dual atmosphere of science and marketing, needing a degree of understanding of that complex animal, the consumer, which far out- reaches that of many other scientific research workers--and probably that of many marketing managers. It needs an understanding, always inadequate, of the emotional content of product judgments. Not in order that this con- tent can be disregarded, but so that it can be given proper weight when this is due. Indeed the judgment of the user is the alpha and the omega of research in our field. At the beginning of the research cycle it indicates the needs and desires of the user. At the end of the cycle it shows how far the techno- logical development has satisfied these needs and desires and provides the basis for so informing the user through advertising.

THE PROMISE AND THE PRODUCT 499 So much is this so, that it is not too big a stretch to regard a toiletries R & D laboratot•v as being composed of a central evaluation group to which are attached subsidiary basic science and product development services. Such an attitude would rarely be reflected in the organization structure of a laboratory, but nevertheless may permeate its philosophy and be made visible in its publications, both internal to the business and external to the world outside. Indeed in the enlightened climate of to-day, it is necessary and right that the external face of our science show itself in this way. 'Science is good, more science is better' has been succeeded already by 'science is good, so what?' and we want now to make it clear that 'science is good because .... ' This is the philosophy we hope to achieve in Unilever, but we are only mortal and I shall now try and expose our frailty and some of our strengths. THE PRACTICE OF EVALUATION Physical evaluation of functional performance Let us accept that products which claim or imply a specific functional performance must perform. And that for such products, this performance is the prime criterion by which they will be judged. A hair colourant must colour hair--or else what is it? In rather closer definition, it is necessary to evaluate in the terms of physical science, the degree of performance of a product which claims or implies a performance measurable in terms of physical science. By the ethical standards of to-day--and perhaps society has improved in some respects, if not all--we believe a product should meet its claims and that these claims should relate to the user's needs. The well-informed, critical society in which we operate will help to keep our ethics bright and shining, but we too must be on our guard against worship of false technical gods, since psychological and emotional satisfactions are also real and some- times sadly underestimated. The requisites for a satisfactory physical evaluation technique are numerous and, ideally, stringent: The effect/phenomenon measured must be in 1: 1 correspondence with that understood by the user to be claimed. The technique be must reproducible,