henry plotkin evolution in mind

Australian Aborigines recognise some 643 living species. They classify them into distinct categories, beginning with a basic division between animals and plants. Animals are then divided into land, sea and winged creatures. Sea creatures are categorised as fish, shellfish and marine turtles, and so on. It is a taxonomy that seems to bear a strong resemblance to the Linnaean classification system that lies at the heart of modern Western biology.

What does this tell us about the structure of human thought, and about the relationship between 'primitive' and scientific thought? These two questions lie at the heart of Peter Worsley's book. Knowledges is a huge, sprawling work which is as fascinating as it is infuriating. Worsley roves the world discussing everything from Aboriginal classification to Antonio Gramsci, from Melanesian navigation to Scottish nationalism, from herbalism to Disneyworld. But he eschews the tradition linear exposition of themes; instead the book reads more like a novel, multilayered, with themes often introduced with their relevance only apparent much later. It is a method that allows the reader to think 'laterally', but it can be mightily frustrating trying to follow an argument through to its conclusion.

What Worsley wants to know is why cultures are simultaneously similar and different. His answer is that knowledge is the product of human activity, but because human activity is varied, so knowledge is plural. As hunter-gatherers Aborigines were driven to establishing a sophisticated biological taxonomy. Western biology, on the other hand, grew out of attempts to systematise knowledge that would be of economic value in the growing commercialised world of nascent capitalism. Very different activities required similar knowledge about the world and hence produced similar forms of classification.

In other areas, however, Aborigines can seem to be backward compared to Westerners. The Aboriginal number system is very limited, while spatial concepts are poorly elaborated - Aborigines, for instance, lack words for 'line' and 'point'. It is not that Aborigines are incapable of such mathematical or spatial concepts, simply that they do not require it within their traditional forms of life. Aboriginal modes of thought, Worsley argues, are not irrational, simply rational within the context of their own social organisation. The rationality of traditional Aboriginal thinking about nature, he points out, is similar to our own 'common sense' way of thinking about nature. Knowledge is plural because we are able to use different conceptual frames for different purposes.

For Worsley, then, the structure of human thought is given in large part by the nature of human activity. For Henry Plotkin, however, it is shaped by our evolutionary heritage. Evolution in Mind is a highly readable and very engaging account of the attempts to use evolutionary theory to understand human thinking. Plotkin provides a swashbuckling tour of the increasingly influential ideas of evolutionary psychology and is never afraid of tackling the more difficult conceptual problems thrown up on the way.

Plotkin puts forward two key arguments. First, he suggests that the mind is not a single general-purpose processor, which uses the same mechanism to complete every cognitive task, but a complex of different 'modules' each specially designed for a particular task - such as acquiring language or coordinating visuo-spatial abilities. Second, he argues that these different modules must all be adaptations, selected for during our evolutionary history.

One such module is believed to be an 'intuitive biology' - an innate, evolved capacity to understand and order the natural world. For evolutionary psychologists, Aborigines have such superb taxonomic skills because these skills are innate and evolved. Indeed, for Plotkin, culture itself is an evolved trait. Culture is such a complex phenomenon, he suggests, that it could not have arisen by accident, only through natural selection.

While evolutionary psychology has made impressive advances in recent years, such an account of human knowledge remains problematic. For instance, while it is true that in other animals complexity is usually a sign of an evolved trait, this is not necessarily so in humans. Some of our most complex cognitive skills - reading and writing, for instance, or mathematical skills - are known to be cultural creations, not evolved traits.

And while there is growing (albeit circumstantial) evidence for the idea of an innate 'language module', the claims for an 'intuitive biology' remain speculative. If knowledge of nature was the product of evolutionary heritage, we would expect it, like language, to be universal: all peoples, not simply hunter-gatherers, should exhibit tracking, classifying and survival skills to the same degree. But place the average European on a desert island and you would quickly find that their skills were less than intuitive. At the very least, this suggests is that such skills are heavily mediated through culture.

Indeed Plotkin concedes that there must be a 'partial decoupling' between biological and cultural evolution. He also acknowledges that cultural change can shape biological evolution. Nevertheless, he insists that cultural evolution is of the same form as biological evolution, except that cultural transmission is non-genetic. But, as Worsley points out, culture does not happen in a blind fashion; people consciously make culture. What is critical for Worsley is the idea of agency: the ability of human beings to make their social and cultural world, not simply have it given to them. It is human agency that distinguishes biological evolution and cultural change.

If Plotkin's vision of knowledge perceives cultural evolution as independent of human agency, the danger with Worsley's pluralist view is that cultural progress disappears altogether. In his haste to dismiss racist views about Aboriginal culture, Worsley seems to suggest that Aboriginal knowledge is not inferior to modern science, simply different. Both, he suggests are forms of 'ethno-science', the attempt to classify and understand the world derived from a particular cultural context.

But such relativism is as blind to human agency as is Plotkin's naturalism. For to deny cultural advance is to deny the progressive impact of human activity over history. It is not racist to suggest that modern science is an advance over Aboriginal ideas of nature (just as it is an advance over Western 'folk' concepts about the natural world). What is demeaning to Aborigines is the idea that science is somehow the property of one cultural group - the peoples of Europe and America. Enthralling as these two books are, they suggest that a more profound understanding of human knowledge requires us see beyond the confines of both naturalism and relativism.