REVIEWSYMPOSIA

Onward and Upward M i c h a e l R u s e , Monad to Man: The Concept of Progress in Evolutionary Biology. C a m b r i d g e , M a s s . : H a r v a r d U n i v e r s i t y Press, 1996. Pp. x + 628. US$49.95

HB.

By John Stenhouse N Monad to Man, Michael Ruse brilliantly dissects the cultural history of evolutionary biology from the eighteenth century to the present. Evolutionary theorists from Erasmus Darwin to Richard Dawkins, he contends, have read metaphysical notions of progress into their biology, turning evolution into a 'secular religion'. Many, though by no means all, have deployed this 'faith' against the traditional religions of the West. Structurally, the book may be considered a fugue consisting of two major themes. The concept of progress, derived from Culture rather than Nature and read into biology, constitutes the fu~t. The second, which for simplicity's sake we might call professionalisation, focuses on the maturation of biology as a professional scientific discipline. Professionalisation in Ruse's view involves a range of activities both practical and intellectual: excluding amateurs, attracting sponsors and research students, its theoretical work manifests such epistemic virtues as simplicity, external consistency, internal coherence, predictive power, etc. etc. The relationship between the two themes, progress and professionalisation, constitutes the heart of the book. Many have assumed a simple, inverse relationship. On this view, still widely held, progressionism dwindled and disappeared as evolutionary biology matured and professionalised. The real story, Ruse shows, is far more complicated and interesting. Modern evolutionary theorising arose during the Enlightenment in the work of Jean Baptiste Chevalier de Larnarck, Erasmus Darwin and Lorenz Oken. Working in an intellectual climate steeped in the progressionist faiths of secular French rationalism, British political

I

9 AAHPSSS, 1998. Published by BlackweUPublishers, 108 Cowley Road, Oxford OX4 1JF, and 350 Main Street, Malden MA 02148, USA

REVIEWSYMPOSIA economy and German idealism, each thinker read progress into their biology. At its birth, Ruse argues, progress constituted evolution's major drawcard to its proponents and flaw to its critics. Evolution remained very much at the level of popular as opposed to professional science during its infancy in the first half of the nineteenth century, as the success of Robert Chambers best-selling Vestiges of the Natural History of Greation (1844) suggests. The Origin of Species did not turn biology into a mature, professional discipline overnight. The rapid conversion of the scientific community meant that 'descent with modification' could no longer be dismissed as pseudo-science. But progress remained embedded in Darwinism, and the retiring sage of Down never constituted a discipline-builder. As a science, Ruse concludes, evolution in Darwin's lifetime constituted at best a promising adolescent. Herbert Spencer and Alfred Russel Wallace thus appear as quasi-religious prophets, commending evolution to a wide audience in the English-speaking world primarily as a surrogate faith for those alienated from Christianity. T.H. Huxley, the Devil's disciple, did more than either Spencer or Wallace to r u m biology into a modern, professional scientific discipline-but only by excluding evolution! While wielding Darwinism out in the wider world to bash Bishops and enlighten working men, Huxley kept it out of professional biology because he regarded it as metaphysically and epistemically problematic. To resolve the tension between progressionist faith and professional biology, he constructed a wall of separation between biology and culture, excluding evolution from laboratory and classroom. A similar situation existed in the United States at the end of the nineteenth century. Virtually all professional scientists had embraced evolution, yet it continued to play a far more significant role in popular culture than in the biological disciplines. The first wave of twentieth-century British evolutionists--E.S. G o o d rich, R.A. Fisher and J.B.S. Haldane--embraced Mendelism without turning evolution into a mature, professional science. Among the next generafion--C.D. Darlington, Julian Huxley and E.B. Ford---only the last-named successfully established a school of professional evolutionists, once again by banning any hint of progressionism in doing so. Julian Huxley, by contrast, failed to heed the growing consensus among professional biologists that one's metaphysics should be kept out of one's science and so his work, though popular outside the profession, was poorly received within. Sewall Wright in the United States professionalised evolutionary biology by excluding concepts of progress--though Ruse discerns Spencerean progressionism underlying Wright's theories. Theodosius 9 ~u-wsss, lo98.

53

REVIEWSYMPOSIA Dobzhansky, arguably the most influential evolutionist of the twentieth century, trod the professional/popular divide more successfully than Julian Huxley by confining his Christian progressionism to his popular writings, and keeping his professional work on micro-evolutionary issues largely value-free. Building on Dobzhansky's Genetics and the Origin of Species (1940), Ernst Mayr, George Gaylord Simpson and G. Ledyard Stebbins forged the modem synthesis and a professionally organised and recognised discipline of evolutionary biology. For all of these men, evolutionism constituted a kind of modem, secular, progressive faith, as Simpson, for one, candidly acknowledged. As professional discipline-builders these men banned overt progressionist discourse from the sacred spaces of laboratory, classroom and professional journal. Much the same pattern characterised the next generation of professional evolutionary biologists, most of whom concentrated on micro-evolutionary problems and eschewed metaphysics. Richard Dawkins constituted the most obvious exception; secular progressionism pervaded his proselytising atheism, despite his protestations to the contrary. The final chapter of the book contrasts the views of three of today's most influential evolutionary biologists: Stephen Jay Gould, Richard Lewontin and E.O. Wilson. Ruse presents Wilson as a latter-day Herbert Spencer for whom the evolutionary epic constituted a 'secular faith'. By failing to respect the professional/popular divide, however, Wilson encountered furious criticism from fellow biologists, notably Richard Lewontin, the population geneticist. The attacks on Wilsonian sociobiology by Lewontin and Gould, Ruse shows, were underpinned ultimately by differing worldviews. Lewontin and Gould, neo-Marxist humanists, regarded Wilson's reductionist sociobiology as a threat to one of their articles of faith--that human societies could and should progress ethically by transcending biology. Different conceptions of progress underpinned the ostensibly 'scientific' controversies that divided Wilson and his critics. Ruse's central argument--that evolutionists have from the beginning incorporated problematic, culturally constructed notions of progress into their biology--I find plausible, mostly well-sustained, and convincing. Historians always find something to quibble about, of course. Too often Ruse failed to understand the outlook of religious believers, especially in the early chapters, and occasionally this verged on caricature. I found the discussion of Adam Sedgwick's attitude to progress (pp. 15-16) inaccurate and unconvincing, and that of St Augustine (p. 21) even worse. The Reverend Thomas Malthus did not argue that ~all efforts at improvement and movement forward are doomed" (p. 28), though the first edition 54

9 AAHPSSS, 1998.

REVIEWSYMPOSIA of his famous Essay on Population was admittedly gloomier than later ones. Archdeacon William Paley did not provide "theological backing" for 'Malthusian pessimism'--blithe optimism would more nearly capture Paley's tone. Ruse presents Thomas Carlyle as a prophet of 'Progress' in an age of 'optimism', a view of Carlyle new to historians of the Victorian period. Charles Hodge, who certainly disliked Darwinism, did not oppose science (p. 280); if anything, he idolised it. During the first half of the nineteenth century, Ruse tells us, "doubts about orthodox religion ~ proliferated and following "the collapse of the foundations of the p a s t . . . Progress" stepped in to give "meaning to life ~ (pp. 28-9). This is too sweeping. Christianity undoubtedly collapsed in the minds of a growing minority of progressive intellectuals during the nineteenth century. But recent historical work hardly supports any larger or more sweeping claim, as Jon Roberts, John Brooke, Ron Numbers and Frank Turner among others have demonstrated. As the examples of Fisher and Dobzhansky demonstrate, even professional evolutionary biologists in the twentieth century have not been unremittingly secular in outlook. Still, none of these nit-picking criticisms undermines Ruse's central thesis. He has shown in impressive detail, in a fascinating series of biographical case studies, that in addition to constituting a steadily maturing science, evolution has functioned over the last two centuries as a secular religion. I unhesitatingly recommend this book to historians of science, religion and modem culture. Religious believers from various traditions, including conservative ones, ought to read it too. Ruse has confirmed what philosophers such as Mary Midgeley and religious critics of evolutionism have long been saying: that to many of its most ardent champions, evolution has constituted a great deal more than mere science. 'True believers' in this secular religion may not like the cold water that Ruse dashes on their faith. That simply goes to show that dogmatic history-despisers may be found outside, as well as within, the institutions of organised religion. Department of History, University of 0tago, Dunedin, New Zealand.

9 AAHPSSS, 1998.

55

REVIEWSYMPOSIA By Hamish Spencer HE only diagram in my facsimile of the first edition Charles Darwin's On the Origin of Species is what we would call today a phylogenetic tree. Natural selection was Darwin's answer to the question of how the organic diversity reflected in the tree came about. But as Michael Ruse convincingly argues in his new book, for Darwin (as well as many other evolutionists), natural selection did not just give diversity, it produced biological progress as well. This progress culminated in our own species, the pinnacle of the evolutionary process. Humans topped the phylogenetic trees of post-Darwinian Europe and America (but not, ironically, that of the circumspect Darwin). Today, however, the concept of biological progress is apparently absent from professional evolutionary biology. Yet at the most recent conference of the Society for the Study of Evolution (SSE) that I attended, phylogenetic trees were everywhere. Somehow, progress and phylogenies have gone their separate ways. No-one at the conference talked about 'lower' or 'higher' taxa in their trees, and the characters used to construct the trees were either 'ancestral' or 'derived' (and never 'primitive' or 'advanced'). Not a whiff of evolutionary progress here! Ruse would have us think otherwise: the concept of progress is pervasive in m o d e m evolutionary thought. Even in the contemporary writings of such overt opponents of biological progress as Harvard palaeontologist Stephen Jay Gould, he finds it lurking. Moreover, this ubiquity really matters to practising evolutionists; it is not just a piece of philosophical esoterica. According to Ruse, the value evolutionary biologists have put on progress in large part explains why evolutionary biology is not considered a 'good, genuine science' (or what he calls in a less inflammatory phrase, "mature science"). And evolutionary biology's immaturity leads to trouble with everyone from creationists, philosophers, other biologists and even evolutionists themselves. Ruse goes about his task of showing that the concept of biological progress has imbued evolutionary science by systematically examining the works of historically important evolutionists for evidence that the evolutionist's theorising was influenced by his (they are all men) views on human progress, even to the point of going well beyond the biology to advance the argument. And without trying too hard in most cases, Ruse finds such evidence. Since almost all of Ruse's pre-1960s evolutionists believed in human progress, they also believed in biological progress (even though it clearly meant slightly different things to different people). Ruse then points out a most interesting feature of these beliefs: any talk of

T

56

9 AAHPSSS,1998.

REVIEWSYMPOSIA biological progress in evolution was not professional science, and the subject could only be raised in popular writing and speaking. Ruse ascribes the genesis of this "separation of church and state ~ to Thomas Huxley, supposedly Darwin's greatest supporter. In spite of his solid commitment to evolution as a fact, Huxley was never a professional evolutionist: his scientific reputation rested on his morphological work and he never touched on evolution professionally. To so many Victorian biologists, especially Huxley, evolution was all but synonymous with progress, and so there could be no professional evolutionary science. The attitude that evolution could not be studied professionally delayed the establishment of the discipline until well into this century. (The biometrician W.F.R. Weldon made a start in an 1893 paper on Neopolitan crabs, but he became embroiled in the debate about the nature of inheritance and died before establishing any lasting school.) Even after evolutionary biology became professional, its practitioners struggled to keep it free from non-epistemic values (like progress). Possibly the most influential evolutionist of this century, Ernst Mayr, in his role as first editor of the SSE's journal Evolution, rejected several papers that so much as hinted at evolutionary progress. It was permissible to be a biological progressionist, so long as one did so outside of one's science, and many (if not all) evolutionists did precisely that. Mayr was (and is) quite candid about his belief in biological (and human) progress. Population geneticist Theodosius Dobzhansky established his scientific standing with numerous non-progressionist scientific articles and books such as Genetics and the Origin of Species. But he also wrote semi-popular books, such as The Biology of Ultimate Concern, in which he articulated his philosophical views including his belief in both evolutionary and human progress. In contrast, Thomas' grandson, Julian Huxley, sullied his reputation--~for all his surface brilliance~, writes Ruse, "Huxley was not of the first rankS--when he violated this divide in his greatest work Evolution: The Modern Synthesis, the last chapter of which is entitled ~Evolutionary Progress ~. In spite of their best intentions, however, none of the modern synthesists was able to keep his ideas about human progress from spilling over into biological progress. For example, Dobzhansky's regular co-author, theorist Sewall Wright, believed in human progress, and his most important contribution to evolutionary biology, the shifting balance theory, is easily interpreted in terms of biological progress. (Ruse's description of the shifting balance theory is one of the few places where I think he has his science wrong. He argues (p. 373) that it is not logically necessary for the adaptive peak to which the population moves under Wright's theory to be higher than that on which it was previously found, implying that Wright's view on human progress led him to give his biology this cast. While Ruse 9

199s.

57

REVIEWSYMPOSIA may be right--no pun intended--about Wright's motivation, the theory does, in fact, contain a reason to expect the second adaptive peak to be higher. In what Wright called Phase 3 of the theory, the population as a whole moves to the higher peak because of inter-demic selection: the subpopulation (or deme) on the higher peak will produce more offspring (because it is better adapted), some of whom will migrate to demes on the lower peak, dragging those demes across the adaptive valley to the higher peak, by virtue of the immigrants' genetic contributions. Ironically, it seems to me, this makes Ruse's claim even easier to substantiate. Among currently practising evolutionists, however, the story is not so clear. Ruse has made good use of the advantage of direct interviews with several men (for leading evolutionists are apparently still ali male). While some, like English theorist John Maynard Smith, are explicit about their belief in biological progress, others such as English game theorist Geoffrey Parker and Niles Eldredge, Gould's collaborator on the paper proposing the controversial theory of punctuated equilibria, are simply not interested in the idea, and even Ruse cannot find it skulking unacknowledged in their work. T h e efforts of the founders of professional evolutionary biology to evict progress from their science have succeeded only too well. Evolutionary science is today quite free from overt ideas of progress but, in contrast to their intellectual forebears, many of its workers don't care about it either. (I wonder how important it is that Maynard Smith was a student of one of the founders, polymath and overt progressionist J.B.S. Haldane, whereas Parker and Eldredge are younger and less tightly linked to this group. If Ruse were to write his book in 2020, would be find any believers in progress?) It is at this point that I find Ruse's argument less plausible. If overt progress has been expunged and, moreover, many evolutionists, especially younger ones, don't support it even in their non-professional writing, how can it be that the concept still prevents evolutionary biology from becoming a respectable science? Is it that this development has not been noticed by the critics, the other biologists and philosophers? Or is it, as it seems to me, that the answer has more to do with subject matter, in particular, the origin of the human species. I know very little and hold even fewer opinions about inorganic chemistry, for example, but I am certain that many chemists hold some opinions, possibly even strong opinions, about evolution (even if they in truth know rather little!). As evolutionary biologists, not only do we live in interesting times, but we also work in an interesting field. In what probably reflects my bias as a practising evolutionary biologist, I found the book came alive once we reached the present century. I would willingly have sacrificed most of Ruse's examination of pre-Darwinian 58

9 AAHPSSS, 1998.

REVIEWSYMPOSIA evolutionists, and even much of that of Darwin and evolution's most successful Victorian populariser, Herbert Spencer (no relation!),for more about today's scientists. (Lauding Darwin's genius while sneering at Spencer's personal life seems a little hackneyed and uninformative, especially given the latter'shigh standing in the eyes of his contemporaries.)Three developments in m o d e m evolutionary biology seem to m e to be worthy of Ruse's analysis and could be very informative of his thesis. The firstarea seems to m e to be a major omission from Ruse's history, and that is the neutral theory. This view, most elegantly propounded by Japanese geneticist Motoo Kimura, holds that the majority of genetic variation observed in natural populations--and by extension most evolutionary change---is irrelevantto natural selection,it is selectivelyneutral. (Ruse explicitly restricts himself to British and American workers after Darwin, but this does not seem to m e to be a good reason to ignore the neutral theory. There were many supporters of the theory working in these two countries, and Kimura's most important work was published in British and American journals and his books were all in English. The neutral theory and the debate it engendered were surely far more important----especiallyin the longer term--than the scrap over sociobiology which Ruse analyses in some detail.)Neutralism was surely the paramount theoretical innovation in evolution in the 1960s, arisingas itdid in tandem with the most important laboratory development, gel electrophoresis. Even for opponents of the neutral theory, itchanged the way they did their evolutionary biology and it clearly has implications for the concept of progress in evolution. If one believes that much evolution is not directed by adaptation through natural selection, what does that mean for one's views about biological progress.> Did the founders of the neutral theory also have particular ideas about societal progress.> H o w much is the neutral theory responsible for the diminution in support for biological progress.> The second development is the resurgence of phylogenetic research in evolution. M y opening paragraph makes it seem as ff phylogenies have always been a central part of evolutionary biology, but this is not so. The m o d e m synthesis was almost hostile to phylogeny. Systematist Mayr rejected any manuscripts submitted to B~:olu6on that focused on trees: they were, in his view, simply 'phylogenetic speculations'. Genet/cs and the Origin of Species had but one phylogeny in the whole book, and that was the oft-reproduced and firmly grounded diagram showing the relationships among chromosomal inversions in Drosophila pseudoobscura and its relatives. It wasn't until the rigorous techniques of cladistics appeared in the 1960s and '70s that phylogenetics slowly crept back into evolutionary science, until today trees are everywhere. I would have liked to learn 9 AAHPSSS, 1998.

59

REVIEWSYMPOSIA what some of the people responsible for this change----grand-student of Dobzhansky, Joe Felsenstein, for instance--think about biological progress. If the Victorians' trees were inherently progressionist, how have today's phylogenies avoided that implication? Or does Ruse think they are still tainted? Given that some cladists--the most prominent being the British Museum of Natural History's Colin Patterson, and Gareth Nelson and N o r m a n Plamick, both of the American Museum of Natural History---claimed that their methods of tree construction were agnostic about evolution, what does that tell us about the link between trees and biological progress? T h e third and most recent area I would have liked to see Ruse analyse is less central in the minds of evolutionists, but probably more fundamental: the origins of complexity. One can hardly mention a definition of biological progress, without touching on biological complexity. While few biologists would go so far so to equate the ideas, almost all think that they are strongly related. In his remarkable book The Origins of Order: SdfOrganization and Selection in Evolution and elsewhere, Smart K a u f ~ a n of the Santa Fe Institute has proposed that one can get 'order for free'. Selforganised order, in Kauffxnan's view, is an emergent property of biological systems, which naturally generate complexity. If the biological world has an innate propensity to increase in complexity, and complexity is tightly linked to progress, does this mean that some version of biological progress is after all a valid scientific concept? Ruse makes it clear in his brief mention of Kauffman's work (p. 536) that he is not concerned about whether or not a valid scientific concept of biological process can logically be incorporated into evolutionary biology, but rather why and how the ideas about progress were excluded. More importantly, how would a scientific concept of progress differ from the concept of biological progress that was banished, according to Ruse's argument, in order for evolutionary biology to become a true science? I suppose it is a compliment to Ruse's engaging style that after more than 600 pages I wanted a little more. And the book would be a lot poorer without many of the revealing vignettes scattered throughout. Who would have thought that one of the best-known popularisers of evolution in late nineteenth-centm'y North America, Alpheus Hyatt, would explicitly argue against the teaching of evolution? Or that Parker, in spite of his progressfree science, should so readily admit to the way in which the 1960s sexual revolution influenced his research on sexual selection and, in particular, what he saw as different male and female interests? Less titillating is Ruse's deduction that natural selection's co-discoverer, Alfred Russel Wallace, was opposed to eugenics because of its class effects, mirroring Haldane's disillusionment some thirty years later. 60

9 ~ , - w s s s , 1998.

REVIEWSYMPOSIA There are a few places where I would challenge Ruse's interpretations and, naturally enough, they involve twentieth-century evolutionists. For example, I would have put Dobzhansky's increasing regard for the importance of selection several years earlier than does Ruse. In the second edition of Generics and the Origin of Species, published in 1941 just four years after the original, selection had already started to become more important. Indeed, natural selection was assigned a pivotal role in the central problem of the origin of species; Dobzhansky's model of speciation by reinforcement appeared in a textbook for the first time. What is interesting is that this change of heart about selection occurred before the experiments that Ruse cites as being responsible were performed. And I do not understand why Haldane is described as failing to be a scientificdiscipline builder. Certainly he was no Dobzhansky, with dozens of students, but the students he did have (e.g., John Maynard Smith) have certainly made their mark. He was editor of the Journal of Genetics for many years and served on the editorial board of the Annals of Eugenics and its successor the Annals of Human Genetics. Oh that I should fail so well! But these are minor quibbles that do not detract from Ruse's main arguments. One of the early reviewers quoted on the book's blurb wrote that he sometimes wanted "to throw it across the room ~. I never had that feeling--what did I miss? Surely biologists, most particularly evolutionary biologists, have long realised that the questions one asks and how one answers them are strongly influenced by the theories one espouses. Data collection is not theory-free nor should it be. Is the problem that those influences need not be iust biological, but pertain to the non-scientific world as well? And would such an admission be the first step on the slippery slope to the latest craze among some sociologists of science, the view that science is iust another human activity, no different from music or literary criticism in its essentials? I think not. Ruse makes a convincing case that scientists' non-scientific beliefs about human progress have almost without exception affected their ideas about progress in evolution. But no one should take this as meaning he thinks science is not something different. Department of Zoology, University of Otago, Dunedin, New Zealand.

9 AAHPSSS, 199s.

61

REVIEWSYMPOSIA By Paul E. Griffiths R

USE'S book covers an extraordinary range of evolutionary thinkers, from Erasmus Darwin to Richard Dawkins. It is structured as a series of vignettes, grouped together by period and to a lesser extent geography. Ruse advances two main theses. First, the concept of progress has played an important role in motivating evolutionary thinkers and that the desire to find progress in nature has shaped the theories they have produced. Second, excluding any explicit mention of progress from evolutionary thought has been a key part of the process of professionalisation and 'discipline building' in evolutionary biology. T h e idea that evolution is progressive has been characteristic of popular science, including that written by leading biologists. Excluding any discussion of progress has been characteristic of professional biology, including work done by the authors of popular science. Ruse argues that for the century after Darwin evolution rarely achieved the status of professional science. The available methods for studying the evolutionary process and the course of evolution did not have the epistemic virtues demanded by contemporaries. At the end of the nineteenth century, "Evolutionary theory was not sufficiently coherent, comprehensive, consistent, predictive for the new biology~. There was little opportunity to base assertions on data, or to establish a collective practice of piecemeal theory building and assessment. What little could be done was not done well: "Epistemic purity was neither achieved, nor was it the primary goal. Evolution was a world-picture, a metaphysics--indeed, a kind of substitute for (or ancillary to) religions (p. 284). Because it lacked suitable epistemic practices, evolution did not afford scientists the opportunity to practice Kuhnian normal science. It was not possible for T.H. Huxley, for example, to build a scientific career on evolution. Evolution might bring him fame, but his scientific status rested on his comparative anatomy. Many biologists were strongly committed to evolutionary progress as part of their cultural world-view, but as late as the 1940s introducing this faith into works for a professional audience was sure to damage one's reputation as a scientist. Ruse uses Julian Huxley as his prime example of someone who suffered for this sin. Dobzhansky was as keen on the mystical Omega point of Teilhard de Chardin as Huxley, but preserved his status by keeping his professional and popular writings distinct. Another theme in Ruse's book is the complex interplay between the idea of progress in nature and that of Progress in society (which Ruse distinguishes with a capital). This is not a simple relationship like that 62

9 AAHPSSS,1998.

REVIEWSYMPOSIA between progress (lower-case) and professionalisation. Many biologists do seem to have sought progress in order to validate their belief in Progress. Others sought validation for both the possibility of Progress and the threat of degeneration. One such was the late-nineteenth-century English biologist E. Ray Lankaster. The influence of Lankaster's 'degenerate' behaviour (in London's whorehouses) on his biological theorising seems to have been substantial: "Convinced that his own emotional capacities had been driven back to the pre-vertebrate level, Lankaster's views on the process of evolution were steeped in bitter personal emotion ~ (p. 227) (this, by the way, is typical of the entertaining style that makes this very long book also very readable). Ruse argues that at least one great modem biologist, George C. Williams, takes a dim view of the possibility of evolution producing desirable human Progress. We are left to achieve Progress through cultural struggle: "We must battle against adaptation and insofar as we succeed, we have done well ~ (p. 483). Ruse does not say very much about the progress/Progress opposition as a theme in evolutionary thought, but it might be a very fruitful subject for inquiry. T.H. Huxley famously put forward such an opposition in his writings on ethics, and the biologist Brian Goodwin has suggested that the opposition in Richard Dawkins' writings between (adaptive, genetic) progress and (freely chosen, cultural) Progress is derived from the traditional theme of the soul's struggle for redemption in a nature corrupted by original sin! An aspect of the progress-Progress relationship that looms large in the later sections of the book is the inspirational role of technological progress in evolutionary theory. The 'obvious' way in which technology progresses has a key role in defining, for figures like Ernst Mayr, the sense in which evolution produces progress. I myself found this last half of Ruse's book the most enjoyable, perhaps because of the extensive use of interviews with the figures involved, and perhaps also because of Ruse's insight into these figures. Ruse has been involved in the philosophy of biology almost since its inception, and many of the characters in the post-Second World War section of the book really come alive. The methodology by which Ruse aims to establish his two main theses is simple. He shows that the presence of a progressive element in a biological theory is underdetermined by the data. He shows that the theorist is committed to the idea that nature, society or both are progressive. He concludes that this prior commitment closed the gap between evidence and theory: "Because progress has been eliminated from professional evolutionism to protect its status as 'professional'--rather than from the conviction that P/progress is wrong--we might expect to find also that P/progress, although hidden, stands ready to influence 9

1998.

63

REVIEWSYMPOSIA the ways that theorists might flU evidential gaps between data and meaning. And this we do find" (p. 484). In some cases Ruse presents overwhelming evidence that his is the correct approach, but in other cases his own theory is, naturally enough, underdetermined by the data. Ruse uncovers a fascinating undercurrent of Spencerian progressivism in Sewall Wright's family background, but the arguments connecting this to Wright's shifting balance theory are complex and indirect. T o his credit, Ruse is not 'in the grip' of his theory, and traces out in some detail how Wright's key idea of an adaptive landscape was used and transformed in the service of an extraordinary range of scientific and ideological agendas. While Ruse's approach to progress is highly productive, there is still room, in my view, to look harder at why progress just seems 'in your face' to so many biologists: "Directionalist common sense surely wins on the very long time scale: once there was only blue-green slime and now there are very sharp-eyed metazoa ~ (Dawkins, quoted p. 467). If there really is nothing underlying this perception, then elaborating the source of the illusion might prove very interesting. Some of Stephen Jay Gould's writings can be read as putting forward just such an 'error theory' of biological progress. If you were to grade an exam whilst plotting the grades it might be some time before you started to flU the 'tails' of the distribution with unusually good and unusually bad essays. If you dated the plots on your graph and then listed "the first appearance of new forms in the marking record" it would appear that the marking process had begun with only very ordinary essays and progressed to more outstanding ones. One Gouldian theme is that even if the process generating new biological forms has no direction whatsoever, the most complex and unlikely forms will take longer to pop up that the simpler and more probable forms. Another, almost equally uninspiring source of 'progress' is that evolution is an incremental process. Although complex forms can be simplified by evolution as well as simple forms being made more complex, it is not possible for complex forms to precede simple ones in their first appearance. If we were convinced by an error theory of this kind, we might argue that belief in P/progress is at least sometimes driven by the investigation of nature, as well as the other way around. Unit for History and Philosophy of Science, Sydney University, Sydney, Australia.

~4

~ AAHPSSS, 1998.