The issue of Geoffrey Lloyd's book in paperback is an opportunity to note a precisely argued and extremely rich, stimulating and helpful book. Its topic is fundamental to the history and epistemology of scientific knowledge, most obviously with regard to the human subject but also in relation to the physical world. Is there a common human mentality – single basic forms to such activities as spatial cognition, the expression of the emotions and reasoning itself – which leads to a shared understanding of the world? Or is human variation in mental activity so great that there are radically different forms of understanding? Developmental and comparative psychologists, ethnographers, linguists, historians and others have done a great deal of research, much of it very recently, and this work displays a confusing mix of empirical argument and axiomatic presumption. Lloyd's project is to take the cross-disciplinary stance necessary to bring the relevant different areas of work into constructive relation, while rejecting global judgement about which side is right and which wrong. ‘I shall argue that the weight to be given to different factors varies across these issues and accordingly that what we conclude on the controversy between unity and diversity, or between the universalists and the cultural relativists more generally, should vary too’ (p. 3). The outcome is a brilliantly clear and succinct guide for the perplexed and a pointer to further inquiry – ‘a clarification of what exactly is at stake in each of the complex issues in question’ (p. 3). The book's forte is to capture briefly the richness of the particular, whether in scientific claims, cultural belief or historical knowledge, and to put conceptual analysis to work in discussing the particular rather than turning it into abstract argument in its own right.

The complexity of what is at stake is crucial. It is simply impossible for one discipline to provide all the necessary evidence, and it is extremely difficult (perhaps impossible) to devise methodologies with which to investigate what is universal and what is not without building in one presumption or another. The most obvious difficulty concerns language, since it is precisely the relativist position to deny the possibility of ultimate adjudication in one language. ‘What vocabulary, other than one that already presupposes our own assumptions, is available to arrive at some comprehension of the variety of ideas that we encounter?’ (p. 108). Lloyd has at least three very important things to say about complexity. The first, and most obvious, is firmly to require cross-disciplinary work. Moreover, in this book he demonstrates, as very few people are in a position to do, what that actually involves. Not only is Lloyd reading the biological, psychological and ethnographic literatures, he is in the remarkable position of being able to draw in, as he does in the latter part of each of his chapters, comparative knowledge of ancient Greek and Chinese cultures. Secondly, Lloyd stresses what he calls the ‘multidimensionality’ of phenomena (like perception, or schemes of biological classification and notions of the self): we are dealing with topics about which it is objectively necessary to tell complex stories – there is ‘a multidimensionality in what it is to be a jaguar’ (p. 147). If we ask whether there is a basic common perception of colour (as claimed in a very influential study by B. Berlin and P. Kay in 1969), it is first necessary to recognize that ‘colour’ has modes of hue, luminosity and saturation and that naming colour may depend on any or all of these. Before asserting that there are basic emotions (which, and how many?), we need to ask whether emotions are distinct or grade into each other, how applicable the English language is for the study of emotions, whether ‘emotion’ is even a useful category for psychology, and so on. Thirdly, he stresses that even supposed single cultures tell complex stories – that achievements in understanding the world vary with time and place even within what we may think of as relatively confined social dimensions. Biology, language and culture do not determine, though of course they shape, forms of understanding: human thought shows remarkable ‘plasticity’.

There are six chapters which in turn consider whether there are universal forms of colour perception, spatial cognition, animal and plant taxonomy and the emotions, and universal notions of health and well-being, and of the self, agency and causation. There has, of course, in recent decades been quite a swing, underwritten by evolutionary biology, towards belief in shared human structures in these areas. Lloyd is not at all disposed to question the objective stance of biology, but he nevertheless finds a number of reasons, in particular domains, to question unqualified universal claims. Two slightly different chapters then follow. The first raises the large matter as to whether the notions of ‘nature’ and ‘culture’ are themselves universal, and he interestingly concludes that the latter may be but the former certainly is not:

In this area in particular, however, it is necessary, as Lloyd stresses, to distinguish between words and concepts. Lastly, he tackles reason itself. ‘What sense, if any, does it make to say that different human beings reason differently?’ (p. 7). Here, the multidimensionality of the question is most obvious, though belief that there is or could be a single form of right reasoning, or for that matter a single thing called intelligence, shows remarkable persistence.