Reflections on the Brain, the Mind and the Soul N o Ghost in the Machine (1989). By RODNEY COTTERILL. Heinemann: London. Pp. 256, 214.95. By Thomas Baldwin Every culture manifests a general view about the relationship between human beings and the rest of nature, since the practices of humans towards each other, other animals, and the rest of nature are informed by views concerning this relationship. At its most abstract level, the question of this relationship has been traditionally regarded as philosophical; it concerns the place of humanity in “the great chain of being” and typically focuses on the issue as to whether human beings are different in kind from all other natural objects, or only different in degree. This question forms the topic of Rodney Cotterill’s new book, but before discussing his thesis I need to say a little about the standard positions on this issue. In the West since antiquity, there have been, broadly, three positions. Some have held that objects of all kinds, including human beings, are solely material, and can be understood in terms of their material structure and relationships. This materialist position was advanced by the Greek Atomists and their Epicurean successors; although the influence of Christianity was then inimical to it, it was revived by Hobbes in the seventeenth century, and was thereafter readily available for his successors. Locke famously entertained this position as a hypothesis in his Essay without either endorsing it or rejecting it. The position which obviously contrasts with this materialist position is that which denies that all objects are material and holds that human beings include an immaterial soul which has an active role in the determination of behaviour. This dualist position was advanced by Plato who argued that only an immaterial soul could gain knowledge of the immaterial essences, or abstract forms, of things. For reasons which I shall come to in a moment, this position was also not favoured by Christianity, and fell largely out of favour until, at much the time that Hobbes revived the materialist position, the dualist position was revived by Descartes, though for a very different reason from that which had inspired Plato. For Descartes, the dialectical role of the concept of an immaterial soul, distinct from the body, was that it seemed to mark out a subjective domain of certainty that provided the foundation for all other claims to objective knowledge.

Descartes’ formulation of the dualist position was enormously influential, though it is rubbish to say, as Cotterill does, that his position “remains virtually unopposed”: in Descartes’ own lifetime it was rejected by, among many others, Hobbes, Spinoza, and Leibniz, and practically no philosopher today subscribes to it. What matters much more than this error, however, is Cotterill’s presumption that the only positions worth considering are the materialist one which he endorses and the dualist one which he rejects. For this misses out

the third option - that of Aristotle, who explicitly rejects both the materialism of the atomists and Plato’s dualism. Aristotle held that objects of all kinds are what they are in virtue of their essential nature, their form, which is not (as Plato held) an abstract object that can exist by itself, but a power or capacity that only exists in the things which it “informs”. Aristotle held that this is as true of human beings as of anything else, and he argued that the way to think of the human mind is to think of it as the form, the distinctive essential nature, of human beings. Because of his view that a form cannot exist by itself, this is not a dualist view; for although form and matter combine in a human being, as in everything else, this is not the dualist association of two independent things. Equally, Aristotle’s position is not a materialist one, for he denies that we can gain a proper understanding of human behaviour simply through a grasp of the material structure of human beings; instead, we need to take account of the mind, our mental powers and susceptibilities, which are not, for Aristotle, explicable in terms of their material basis.

My reason for stressing Aristotle’s naturalist position is not just historical - though since Cotterill represents himself as telling a historical story, it matters quite a bit that he omits altogether the position which was dominant from antiquity to the seventeenth century and which became orthodoxy within Western Christianity (hence, for example, the insistence that the immortality of the soul requires the resurrection of the body: for within an Aristotelian scheme the human soul cannot exist except as the soul, or mind, of a human body). The really important point is that one can reject dualism without falling back on Cotterill’s materialism: tertium datur. For one can reject a “bottom-up” materialist reduction by maintaining that organic systems, or certain species of them -such as human beings - possess properties that are both not explicable in terms of their material basis and are important for an understanding of their behaviour. The case of artefacts provides an easy analogy here: why do chairs have the shape they have? Not because of the material out of which they are constructed - but because of the human use for which they have been constructed.

Of course, to identify this third naturalist position as an alternative to those which Cotterill identifies is not to show that it is preferable to his materialist position. But it does suffice to show that Cotterill does not establish his position; to do so he would have had to vindicate a

’ reductive materialist account of our mental life as against a non-reductive naturalist account. A key issue in such a debate would be the account offered by materialists of the content of thoughts and thus of human rationality. It is held by some influential philosophers, especially Donald Davidson, both that the explanation of intentional action makes essential reference to the desires and beliefs which render action rational, and that desires and beliefs satisfy a condition of general coherence which is incompatible with a materialist explanation of their content. Thus for

Davidson our “common sense” psychology is not reducible to a materialist scheme of explanation: so his account exemplifies the general form of the Aristotelian position, and it is certainly not a dualist position. So much the worse, some (e.g. Paul Churchland) then say, for common sense psychology: a properly scientific understanding of the mind should lead us to reject it and replace it by concepts which do admit of a materialist explication. Yet this seems dubiously coherent - for how could it be rational to repudiate the category of rational thought?

Of course, there are many who dispute Davidson’s anti-materialist arguments, and the issue is one of the most contested ones in contemporary philosophy. But my reason for labouring this criticism of Cotterill is that, having set himself to write a book about man’s place in nature, he did not then bother to acquaint himself properly either with the bare outlines of historical debates on this topic or, more importantly, with the current state of the debate. Instead, he chose to provide a survey of important developments in the understand- ing of the human brain, spiced up from time to time by polemical diatribes against the dualist position and rather silly remarks about free will and religion. Had Cotterill in fact just chosen to write a book about the historical growth in our understanding of the brain I am sure he would have written a much better book. But I should add that the present book is rather over- burdened with technical vocabulary and under- equipped with informative diagrams. My experience, as the type of general reader whom Cotterill should be aiming at, was that where I was already familiar with the vocabulary and some of the details under discussion, I was able to follow his discussion. But where I was not already familiar with some of the material (e.g., on neural networks) I found the discussion hard going. I also noticed some errors - e.g., Cotterill confuses schizophrenia with the condition of someone who is schizoid, and he quite wrongly attributes to Freud an attempt to account for schizophrenia.

In the bulk of this review, I have been very critical of Cotterill. But perhaps my complaint should be directed not so much to him as to the community of natural scientists to which he belongs. For it seems to me scandalous that such an ill-informed work should be published as if it were a serious contribution to the general understanding of human nature; if I were to take sides in a similarly ill-informed way in a debate within psychology, or some other natural science, I am sure I would never find a publisher. It ought not to be any more acceptable to sound off about philosophical issues without studying them carefully than it is to sound off about scientific issues without studying them carefully.

Thomas Baldwin, Faculty of Philosophy, University of Cambridge, Sidgwick Avenue, Cambridge CB3 9DA, UK.

Developmental Biology at Ciba: Sequel to the 1975 Meeting Cellular Basis of Morphogenesis, Ciba Symposium I44 (1989). Edited by DAVID EVERED AND JOAN MARSH. John Wiley and Sons, Chichester. Pp. 307, f32.50. By Jeremy Green Fifteen years ago, a group of developmental biologists got together at the CIBA Foundation in London to discuss pattern formation. Model-building was much in evidence and concepts of positional information were still fresh, while the experiments described were mostly of a classical flavour involving much snipping and grafting. Somehow there was a gulf between the theory and the experiments. Even then, though, there were signs that the gulf might be bridged by the fly geneticists. Garcia-Bellido talked about selector genes, but above all Sydney Brenner, the symposium chairman pugilistically forecast that a “bottom up” (genes-to- phenotypes) approach would prove the most successful. The proceedings of that meeting were published as CIBA volume 29 and the present volume, which covers a 1988 meeting, is effectively its sequel. The similarities and contrasts between the two are illuminating - not least because Brenner’s prediction seems to have been right.

The two volumes are linked by the durable CIBA formula: put a few top scientists together in cosy surroundings to discuss their work and publish what happens to high production standards in hardbound format. As well as the presented papers, the subsequent discussions are also transcribed and provide lively illustration of personalities and issues. (Dramatic dialogue as a means of presenting science is worth an essay in itself: Galileo used it to good effect in his books, but who other than CIBA uses it now?) Participants in these meetings must also know they will be cross-examined by their peers, and this cannot help but maintain a quality and thoughtfulness lacking in books made from more routine conferences.

The book is introduced and summarised by Lewis Wolpert whose main theme is to urge us all to build models. Antonio Garcia-Bellido is also in philosophical mode and calls for more studies of cells as developmen- tal units. Peter Lawrence, in typical provocative form, sets off two stimulating arguments, one on the concept of stable cell states and the other on intra-compartmen- tal morphogenetic gradients versus mosaic interactions in Drosophila embryos. Sander does not give a paper but contributes significantly to the discussions, his knowledge of insects other than Drosophila providing perspective - mostly positive - on the fruit-fly story. Here we see the most resounding success of the last fifteen years: the chapters on early Drosophila axis formation by Nusslein-Volhard and Struhl should serve as landmark reviews. Their descriptions are almost on the level of algebra, and begin to provide that sense of