There is a famous passage in one of Freud's lectures where he says that in the course of human history the view that human beings are the centre of the universe:
has had to submit to two major blows at the hands of science. The first was when they learnt that our earth was not the centre of the universe but only a tiny fragment of a cosmic system of scarcely imaginable vastness. This is associated in our minds with the name of Copernicus... The second blow fell when biological research destroyed man's supposedly privileged place in creation and proved his descent from the animal kingdom and his ineradicable animal nature. This revaluation has been accomplished in our own days by Darwin, Wallace and their predecessors, though not without the most violent contemporary opposition.1
The impact of Charles Darwin's theory of evolution was undoubtedly revolutionary. Marx's response to the appearance of The Origin of Species in 1859 is well known. In a letter to Ferdinand Lassalle he wrote:
Darwin's book is very important and serves me as a natural-scientific basis for the class struggle in history... Despite all deficiencies, not only is the death-blow dealt for the first time here to 'teleology' in the natural sciences, but its rational basis is empirically explained.2
More than anything else it is the revolutionary character of Darwin's theory that constitutes the basic theme of leading American philosopher Daniel Dennett's new book, Darwin's Dangerous Idea. He compares the theory of evolution by natural selection to 'universal acid: it eats through just about every traditional concept, and leaves in its wake a revolutionised world-view'. Dennett makes even stronger claims for Darwin than did Freud or Marx:
If I were to give an award for the best single idea anyone ever had, I'd give it to Darwin, ahead of Newton and Einstein and everyone else. In a single stroke, the idea of evolution by natural selection unifies the realm of life, meaning, and purpose with the realm of space and time, cause and effect, mechanism and physical law.3
Yet, despiteor, perhaps, because ofits intellectual power, the theory of evolution continues to attract the 'violent...opposition' to which Freud refers. Dennett notes the different forms this resistance takes. Some of it comes from Christian fundamentalists seeking to prove the literal truth of the Book of Genesis. This is reflected in the efforts, particularly in the United States, to have 'creation science' (ie the Christian myth) taught alongside evolutionary biology in schools. This propaganda campaign has undoubtedly had some effect. Dennett quotes a Gallup poll which reported in June 1993 that '47 percent of adult Americans believe that Homo sapiens is a species created by God less than ten thousand years ago.'4 In November 1995 the Alabama state school board voted to insert in all biology textbooks a warning that evolution is 'theory, not fact'.5
Yet Dennett is less concerned with developments such as these, alarming though they are, than with the resistance evinced toward the theory of evolution by many philosophers, scientists, and other intellectuals. He includes in this category even such a brilliant populariser of modern biology as Stephen Jay Gould and the great linguistic theorist Noam Chomsky. His book is thus intended both to clarify and to expound Darwin's theory, and to defend it against those he regards as misguided critics.
In doing so, Dennett comes at the argument from a specific angle. He is by background a philosopher of mind, the author of a number of well known books, notably Brainstorms (1978) and Consciousness Explained (1991). As the title of the latter book indicates, Dennett is hardly the kind of analytical philosopher happy to concentrate on the exquisitely precise examination of details of linguistic usage. He isn't afraid to take on big subjects.6
There is, moreover, a unifying theme that connects Darwin's Dangerous Idea with Dennett's earlier writings. In the latter he has been concerned to develop what might be described as a non-reductionist materialist theory of the mind. In other words, he has sought to find a way of treating the mind as a natural phenomenon, whose activities are continuous with those in the physical world, while at the same time recognising that human beings are 'intentional systems' whose behaviour cannot be explained without ascribing to them beliefs, desires and other mental states. Dennett accepts that that these states cannot be reduced to corresponding physical states, but he wants to avoid treating them (as many contemporary philosophers still do) as partaking of some mysterious 'mind--stuff' fundamentally different from the physical world.7
Dennett has attempted to clarify the issues involved by drawing on Artificial Intelligence (AI), a discipline that came into existence to try to understand the computers it helped to create. He argues that AI can help us to understand the human mind in two ways. First, to the extent that computers do things that are analogous to what minds do, they show that mental activity is best understood less in terms of the physical hardware it depends on (the brain and nervous system in the case of humans), but rather in terms of the functions which it realises. AI suggests that these functions do not necessarily have to be performed by physical organisms like us. Computers must, at least for some purposes, be treated as intentional systems.
Secondly, AI explains how computers perform their functions by analysing them into component sub-systems each of which undertakes tasks which require less intelligence than those of the computer as a whole, and each of which is in turn composed of progressively smaller and less intelligent sub-systems. Dennett suggests we think of computers as composite beings made up of homunculi (tiny men): 'The highest level design breaks the computer down into a committee or army of intelligent homunculi with purposes, information and strategies. Each homunculus in turn is analysed into smaller homunculi, but, more important, into less clever homunculi'.8
Dennett believes that AI can throw light on the apparent mystery of how intentionalityall the complexity and richness of human mental lifecan somehow emerge from brute, mindless matter. The analogy of the computer, composed of progressively less intelligent sub-systems (increasingly stupid homunculi), shows that there is no sharp dividing line between mind and matter but a series of continuous gradations which blur this distinction. The mind itself straddles the boundary between the mental and the 'merely' physical since, like the computer, it is composed of a number of sub-systems each of which displays less intentionality than the system as a whole:
In an organism with genuine intentionalitysuch as yourselfthere are, right now, many parts, and some of these parts exhibit a sort of semi-intentionality, or mere as if intentionality, or pseudo-intentionalitycall it what you likeand your genuine, full-fledged intentionality is in fact the product (with no further miracle ingredients) of the activities of all the semi-minded and mindless bits that make you up... That is what a mind isnot a miracle machine, but a huge semi-designed, self-redesigning amalgam of smaller machines, each with its own design history, each playing its own role in the 'economy of the soul'.9
This view of mind is brilliantly developed in Consciousness Explained. Here in particular Dennett seeks to refute the conception of mental life inherited from Descartes according to which there is 'a special centre in the brain' which is the focus of consciousness. He offers in its place 'the Multiple Drafts model of consciousness', according to which:
all varieties of perceptionindeed all varieties of thought or mental activityare accomplished in the brain by parallel, multitrack processes of interpretation and elaboration of sensory inputs. Information entering the nervous system is under continuous 'editorial revision'.
There is no specific point which can be identified as 'the moment of consciousness'; what we call consciousness is simply the effect of all these simultaneously occurring processes. The mind must be seen as a 'Joycean machine', 'a cobbled together collection of specialist brain circuits', which functions by 'yoking together these independently evolved specialist organs in common cause and thereby giving their union vastly enhanced powers'.10
But this theory, Dennett argues, is only one strategy which materialist explanations of the mind can pursue. 'There are two paths to intentionality,' he writes. That pursued in books like Brainstorms and Consciousness Explained represents what he calls the 'synchronic path'. In other words, it uses AI to help offer a static analysis of how human brains as they exist now, as organs of a certain living species, perform complex mental functions. But there is another route to the same goal: 'The Darwinian path is diachronic, or historical, and concerns the gradual accretion, over billions of years, of the sort of Designof functionality and purposivenessthat can support an intentional interpretation of the activities of organisms (the "doings" of "agents").'11 In other words, the theory of evolution offers the possibility of writing a natural history of the mind, of explaining how all the rich diversity of mental life gradually emerged from a physical world from which, originally, it was utterly absent.
The key problem that Darwin addressed was that of design in nature. Philosophers from Aristotle to the theologian William Paley had pointed to the infinite number of ways in which the parts of the natural world seem to be designed to achieve certain ends. Thus, to use a standard example, the giraffe's long neck allows it to feed off the leaves of trees. Before Darwin, the usual way of explaining all these features was teleologically. A teleological explanation accounts for something in terms of the goal or purpose it serves (what Aristotle called its 'final cause').12 But to identify a purpose is also to presume the existence of some agent whose purpose it was. In some cases this is quite unproblematic. We don't worry about saying that the purpose of a house is to provide shelter because we know that houses are built by human beings, organisms who are, among other things, capable of consciously selecting goals and acting in the light of them. But to discover purposes in nature is to invoke a super-agent, a creatorin other words, God.
As Marx saw, Darwin's historic significance lay in the fact that he dethroned teleology from the privileged place that it had previously enjoyed in the explanation of nature in general and of living organisms in particular. In Dennett's words, 'Darwin explains a world of final causes and teleological laws with a principle that is, to be sure, mechanistic butmore fundamentallyutterly independent of "meaning" or "purpose".'13 This principle is natural selection.
Here is Darwin's own summary of his basic idea:
If, during the long course of ages and under varying conditions of life, organic beings vary at all in the several parts of their organisation, and I think this cannot be disputed; if there be, owing to the high geometric powers of increase of each species, at some age, season, or year, a severe struggle for life, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of existence, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, I think it would be a most extraordinary fact if no variation ever had occurred useful to each being's own welfare, in the same way that so many variations have occurred useful to man. But if variations useful to any organic being do occur, assuredly individuals thus characterised will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will tend to produce offspring similarly characterised. This principle of preservation, I have called, for the sake of brevity, Natural Selection.14
As Dennett observes, Darwin's argument relies on a 'few general conditions'. These are: (1) 'the struggle for existence'in other words, populations of organisms compete to survive and reproduce in environments where typically not all can succeed; (2) the fact that organisms varyto put it in modern terms, small differences in the DNA codings that govern all organisms' genetic constitution occur randomly; (3) 'the strong principle of inheritance'variations are liable to be passed on from parents to offspring; (4) differential 'fitness': relative to a specific environment, some variations will allow organisms to reproduce more successfully than others. Granted these conditions, 'the resulting process would necessarily lead in the direction of individuals in future generations who tended to be better equipped to deal with the problem of resource limitation that had to be faced by the individuals of their parents' generation'.15
Natural selection allows Darwin, as Marx put it, to explain the 'rational basis' of teleology. All the apparent wonders of designincluding the human mind and its creationsturn out to be the products of a mindless mechanical process. Dennett calls natural selection an 'algorithmic process': algorithms are formal procedures like long division which, whenever they are applied, can be guaranteed to produce certain results. He imagines Darwin saying: 'Give me Order,...and time, and I will give you Design. Let me start with regularitythe mere purposeless, mindless, pointless regularity of physicsand I will show you a process that eventually will yield products that exhibit not just regularity but purposive design'.16
Human beings are precisely such purposive designers, but they are also among the products of this process. Intentionality is something that gradually emerges through a series of intermediary stages, as species of organisms develop that have the ability to act on their environment in order to achieve certain purposes. In most cases the selection of these objectives and of the means required to attain them are just wired in: they are fixed in the genetic coding of the species. But in certain conditions, variations occur which confer selective advantages on organisms that have a far greater degree of flexibility in choosing goals and the means of attaining them.
At the end of this particular evolutionary sequence (which is simply one among many: we aren't the point of evolution), Homo sapiens sapiens emerges. Thus, '[b]efore intentionality can be fully fledged, it must go through an awkward, ugly, featherless pseudo-intentionality.'17 Just as in Dennett's 'synchronic' explanation of consciousness, mind appears historically through a succession of steps along a continuum, in which intentionality gradually appears in forms which (relative to the final step) appear crude and stupid.
Much of Darwin's Dangerous Idea is devoted to developing and articulating this interpretation of natural selection, partly by applying it to a variety of cases and partly by defending it against critics. Typical of these critics, Dennett contends, is their resort to what he calls 'skyhooks'. A skyhook descends from the air to support something on the ground beneath. For Dennett, a skyhook is 'a "mind-first" force, or power, or purpose, an exception to the principle that all design, and all apparent design, is ultimately the result of mindless, motiveless mechanicity'. The prime instance of a skyhook is the mind itself. Dennett offers forceful criticisms of philosophers who deny that the mind can be explained in evolutionary terms, and of what he believes to be Chomsky's closely related argument that language is not a product of natural selection.18
Dennett also targets Stephen Jay Gould for criticism. He argues that, despite the brilliance of Gould's popular expositions of evolutionary theory, 'he is opposed to the very idea that evolution is, in the end, just an algorithmic process.' Dennett focuses on what he believes to be various instances of this fundamental tendencyin particular, Gould's critique of 'hyper-Darwinian' efforts to turn every organic feature into an evolutionary adaptation, his theory of 'punctuated equilibrium', which holds that evolution proceeds, not as Darwin claimed, through continuous, gradual changes, but catastrophically, with 'long periods of stasisequilibriuminterrupted by sudden and dramatic periods of rapid change', and his argument in Wonderful Life that natural history is characterised by 'radical contingency'.19
Gould is an important figure, both because the skill and imagination of his writings are such a powerful counterweight to vulgar anti-scientific prejudices, and because, as a socialist scholar, he has very effectively used his grasp of evolutionary theory to resist contemporary versions of Social Darwinism, which invoke natural selection to justify social inequality. Therefore, when I read Dennett's critique, my sympathies were, to start off with, strongly on Gould's side. Yet Dennett makes out a powerful case, though on the first two issuesadaptationism and punctuated equilibriumthis takes the form not of a refutation of Gould but of a demonstration that the differences between him and more orthodox Darwinians are a lot less than meets the eye. On the third issue, however, Dennett is absolutely spot on.
Consider this passage, where Gould puts forward the image that informs his case for 'the controlling power of contingency in setting the pattern of life's history and current composition':
I call this experiment 'replaying life's tape'. You press the rewind button and, making sure you thoroughly erase everything that actually happened, go back to any time and place in the past... Then let the tape run again and see if the repetition looks at all like the original. If the replay strongly resembles life's actual pathway, then we must conclude that what really happened pretty much had to occur. But suppose that the experimental versions all yield sensible results strikingly different from the actual history of life? What could we then say about the predictability of self-conscious intelligence? or of mammals? or of vertebrates? or of life on land? or simply of multicellular persistence for 600 million difficult years?20
I've always found it very difficult to understand what Gould is saying here. However far back we rewind the tape, we will find ourselves confronted with a set of conditions representing the state of affairs at the point to which the tape has been wound. These conditions (along with the laws of nature) will surely significantly constrain the subsequent path taken by life. It doesn't follow that (as strict determinists would hold) that these conditions and laws require that only one outcome (what actually did happen) is possible. But if only a limited number of paths are at any stage possible, given these conditions and laws, then we are a long way from 'radical contingency'. One sort of constraint, Dennett suggests, is that certain adaptations are likely, in a wide range of environments, to confer selective advantage. 'Replay the tape a thousand times, and the Good Tricks will be found again and again, by one lineage or another'.21
Dennett is an exceptionally able philosopherenergetic, inventive, imaginative, with very interesting things to say about a wide range of important issues. Darwin's Dangerous Idea is full of clever and provocative arguments covering a sometimes bewildering variety of often highly technical questions and written in lively and accessible prose. Dennett is also a formidable critic and polemicist: the passage, for example, where he demolishes appeals to religious faith as an alternative to reason in establishing the truth about the origins of life is a delight.22 I can't think of many recent books that I've enjoyed as much or that have stimulated me more.
Butyes, I'm afraid there is a but. Its source lies in the excessive ambitions that Dennett reveals for the concept of evolution by natural selection. He believes, as we have seen, that Darwin's is the most important single scientific idea. This seems to be tied up with the notion that it 'promis[es] to unite and explain just about everything in one magnificent vision':
If redesign could be a mindless, algorithmic process of evolution, why couldn't that whole process itself be the product of evolution, and so forth, all the way down? And if mindless evolution could account for the breathtakingly clever artifacts of the biosphere, how could the products of our own 'real' minds be exempt from an evolutionary explanation? Darwin's idea also threatened to spread all the way up, dissolving the illusion of our own authorship, our own divine spark of creativity and understanding.23
So evolution is responsible for Life, the Universe, and Everythingeverything, that is, from the origins of the universe to the course of human history. In fact, Dennett's attempt to demonstrate this all the way downie, for the development of the physical world prior to the emergence of lifeis pretty feeble. He offers some 'semi-Darwinian' theories of the universe but since, he admits, these do not involve one of the crucial features of natural selection 'the Struggle for Existence'the analogy detected here between the history of the cosmos and the history of life is a weak one.24
Undoubtedly Darwin's theory was one of a number of scientific breakthroughsamong the others were the discovery of the second law of thermodynamics and the formulation of the theory of general relativitywhich require us to view nature historically, as a complex of processes of development. Such a view makes it possible to defend on scientific grounds a naturalistic or materialistic conception of the world in which there is no sharp distinction, on the one hand, between the various domains of the physical worldcovered by such separate disciplines as physics, chemistry, and biologyand, on the other hand, between the physical world as a whole and the human, social world.
But viewing nature (including human nature) as a whole requires us to think of it as stratified. We must, in other words, distinguish between different levelsthe physical, the chemical, the organic, the human, and so oneach of which has its own distinctive complexity, its own emergent properties, which cannot be simply reduced to those at the level below it. It follows that the mechanisms at work at one levelsay, those governing the formation and development of universescan't be assumed to be identical with those operating at anotherthose, for example, responsible for the evolution of organic life.25
Dennett is perfectly aware of these general points. Indeed, his theory of consciousness is precisely an account of human mental life as a set of emergent properties that arise from the physical and biological but which must be explained in terms of the mechanisms operative at its own level. He tries to distinguish 'reductionism, which is a good thing, from greedy reductionism, which is not':
The most common fear about Darwin's idea is that it will not just explain but explain away the Minds and Purposes and Meanings that we all hold dear... This cannot be a sound fear; a proper reductionistic explanation of these phenomena would leave them still standing, but just demystified, unified, placed on more secure foundations... A more reasonable and realistic fear is that the greedy abuse of Darwinian reasoning might lead us to deny the existence of real levels, real complexities, real phenomena.26
That this is indeed a reasonable and realistic fear is shown by the fact that when Dennett seeks to move evolution 'all the way up' to explain the human world he is guilty of precisely the sort of greedy reductionism that collapses the different levels of nature into one other.27 The main form that this takes is Dennett's potentially disastrous alliance with sociobiology. Sociobiology is essentially a form of biological determinism, which seeks to explain the behaviour of human individuals and the patterns of social life on the basis of their genetic structures.
Its ideological implications are made evident by the very title of one of sociobiology's founding texts, Richard Dawkins's The Selfish Gene (1976). Dawkins declares, 'We are survival machinesrobot vehicles blindly programmed to preserve the selfish molecules known as genes'.28 Human beings must thus be seen essentially as the bearers of their genes, who use them as means to maximise their reproductive chances. The reactionary uses to which this idea can be put were made clear in Richard Herrnstein's and Charles Murray's recent book The Bell Curve, which argues that black Americans' poverty can be explained by their biologically determined inferior intelligence as measured by IQ tests.29
It should be emphasised that Dennett at no point shows any sign that he shares such repellent social views. The closest he comes in Darwin's Dangerous Idea to directly expressing a political opinion is when he criticises the 11-plus, which was, of course, based on the idea of examining children to identify innate differences in their abilities.30 At the same time, however, the book is full of approving references to Dawkins's ideas and work, and it carries on its back cover an endorsement by him as 'a surpassingly brilliant book'. Dawkins and Dennett defend, broadly speaking, the same orthodox Darwinian conception of evolution as a process proceeding through a succession of small changes which cumulatively have the effect of producing highly complex phenomena.31
The most substantial evidence, however, of Dawkins's influence on Dennett lies in the latter's adoption from him of the concept of the meme. The meme is supposed to function in the human world as genes do at the biological level. It is, according to Dawkins, 'a unit of cultural transmission, or a unit of imitation'. Just as genes use organisms to reproduce themselves, so memes use minds. The same mechanisms govern the behaviour of both: 'Meme evolution is...a phenomenon that obeys the law of natural selection exactly.' Dennett suggests that this claim can be summed up by the slogan, 'A scholar is just a library's way of making another library'.32 Human beings are merely the passive bearers of an impersonal process of 'memetic evolution'.
When I first came across Dennett's enthusiasm for memes I groaned out loud. The meme is so manifestly a really bad idea. But before I explain why, it's worth noting how memes are supposed to get sociobiology out of the really big hole it has dug for itself. The obvious difficulty with biological determinism is that there are important features of human beings that make it impossible to see them as just vehicles for their genes' reproductive strategies. Innovation among other species typically takes the form of genetic mutation. A new adaptation which equips the organisms in question to cope better with their environment is a result of a random change in DNA codings. But humans' peculiar intellectual powers give them a far greater degree of flexibility. They can imagine new ways of acting on the world that depend on no genetic mutation but merely require some alteration of technology or of social organisation. Moreover, an innovation, once made, can be passed on by cultural meansour possession of language allows us to communicate new ideas not merely directly but, by means of oral tradition or writing, from one generation to another, thus ensuring that innovations become a permanent possession of the species, without any genetic change.
Dennett is perfectly well aware of these facts, and of their implicationthat humans, thanks to their intellectual and linguistic powers (and, closely connected with these, their ability to co-operate socially through labour), can develop independently of their biological structures.33 This is where memes come in. They serve to patch up a potentially disastrous gap in sociobiology's genetic determinism by showing human cultural development operates in precisely the same way as biological evolution. Or rather they would play this role if the concept of the meme were defensible. But it isn't.
There are three reasons for rejecting the idea of the meme. First, it is far too vague. Dennett offers the following examples of memes: arch, wheel, wearing clothes, vendetta, right angle, alphabet, calendar, the Odyssey, calculus, chess, perspective drawing, evolution by natural selection, Impressionism, Greensleeves, deconstructionism, co-operation, music, writing, education, environmental awareness, arms reduction, the Prisoner's Dilemma, The Marriage of Figaro, Moby Dick, returnable bottles, the SALT agreements.34 But this is a hopeless jumble of different kinds of human creationsocial institutions and practices, philosophical schools, scientific concepts, theoretical arguments, specific art works, and so on. Dennett wholly fails to offer any criteria by means of which a meme is to be identified.
Maybe he thinks that this doesn't matter, that anything that succeeds in being culturally transmitted, for whatever reason, counts as a meme. But what is it that is being passed on? Really successful ideasabove all, scientific conceptsare highly specific, and they succeed precisely because of this specificity. To take Dennett's own preferred idea, that of natural selection, as he himself puts it:
Cute ideas about evolution had been floating around for millennia, but, like most philosophical ideas, although they did seem to offer a solution of sorts to the problem at hand, they didn't promise to go any farther, to open up new investigations or generate surprising predictions that could be tested, or explain any facts they weren't expressly designed to explain. The evolution revolution had to wait until Charles Darwin saw how to weave an evolutionary hypothesis into an explanatory fabric composed of literarally thousands of hard-won and often surprising facts about nature.35
But the concept of meme isn't just vague: it is, secondly, atomistic. Like genes (at least in sociobiological treatments), memes seem to function in isolation from one another, each facing up to the force of natural selection on its own. But this is quite wrong. What we call scientific concepts, for example, are in fact complex wholes composed of a number of different 'concepts' and propositions. Once again natural selection serves very well to illustrate the point. As we saw in the previous section, this 'idea' in fact consists of a set of distinct assumptions 'the Struggle for Existence, genetic mutation, the 'strong principle of inheritance', and differential 'fitness'from which certain conclusions may be inferred. Ideas don't confront whatever tests of their truth and usefulness to which they are subject on their own, but as parts of larger wholes.36
Finally, the concept of meme ignores not only the theoretical context of concepts, but also their historical context. The formation and, even more important, the reception of ideas depends on a constellation of circumstances which can't be reduced to the mere interaction of atomistic memes. The triumph of Adrian Desmond's and James Moore's brilliant biography of Darwin lies in their success in reconstructing the environmentVictorian capitalism, Malthusian ideology, political and theological controversyin which he groped towards the concept of natural selection, hesitated long before publishing his discovery, and finally enjoyed widespread (though bitterly contested) acceptance.37
Dennett shows no awareness of these fundamental weaknesses of the concept of meme. But his use of it is considerably more hesitant in Darwin's Dangerous Idea than it was in Consciousness Explained. Thus he says that 'whether such [ie meme] evolution is weakly or strongly analogous or parallel to genetic evolution, the process that Darwinian theory explains so well, is an open question.' This is potentially a very damaging concession, since the weaker the analogy, the bigger the obstacle to applying biological reasoning to the explanation of human behaviour. And when Dennett comes to discuss sociobiology directly, he retreats further in the face of its critics' fundamental argument that most successful human practices can be explained, not genetically, but as a result of cultural innovation and transmission.38
His bark is thus worse than his bite. Closely examined, Dennett's arguments generally avoid the 'greedy reductionism', or biological determinism, of Dawkins & Co. But some of his general formulationsin particular his adoption of the idea of memesopen the door to sociobiology, and must therefore be rejected.
There is something of the 19th century mechanical materialist about Dennett. This is less a matter of the detail of his argumentshis work in the philosophy of mind in particular succeeds remarkably well in avoiding reductionismthan of style and sometimes of formulation.39 In these respects he is rather reminiscent of one of the greatest of the pre-Marxian materialists, Ludwig Feuerbach. Marx wrote of him, 'Insofar as Feuerbach is a materialist he does not deal with history, and insofar as he considers history he is not a materialist.'40
Precisely the same can be said of Dennett. He is a brilliant expositor and defender of Darwin's theory, and he is enormously successful at using Darwin's insights to develop a materialist theory of mind. But when he comes to look directly at the human world itself, the best he can come up with is a theory of social evolution which accords primacy to memesthat is, to ideas. The human is thus equated with the mental, just as it was by Enlightenment philosophers such as Helvetius. The structures specific to the human worldthe forces and relations of production and the social relations arising on their basissimply do not exist for Dennett.
It is perhaps symptomatic that in his discussions of the 'diachronic' historical development of intentionality Dennett ignores the relationship between mental and practical activity. By contrast, Engels, while accepting Darwin's broad conception of evolution, stresses the role played by the emergence among the ancestors of Homo sapiens of forms of co-operative labour in the development of both the brain and language, an interpretation supported by recent research.41 Dennett conceives the mind as physically embodied, but detached from social practice.
It is characteristic of mechanical materialists that they highlight religion as the main obstacle to intellectual (and therefore social) progress. There is something of this old fashioned obsession with religion as the main enemy in Dennett. Thus, when seeking to explain what he sees as Stephen Jay Gould's resistance to Darwin, he invokes what he calls 'Gould's religious yearnings'. But the only hard evidence he comes up with for these yearnings is Gould's taste for biblical languagehardly convincing since Gould is very far from being the first skilful writer of English prose to have raided the King James Bible for a good turn of phrase.42
Dennett is indeed puzzled by the final sentence of Wonderful Life: 'We are all the offspring of history, and must establish our own paths in this most diverse and interesting of conceivable universesone indifferent to our suffering, and therefore offering us maximum freedom to thrive, or fail, in our own chosen way'.43 He comments: 'Curiously enough, this strikes me as a fine expression of the implication of Darwin's dangerous idea, not at all in conflict with the idea that evolution is an algorithmic process.'44 Quite so. Doesn't this suggest that the problem with Gould isn't his alleged anti-Darwinism or religious yearnings, but rather that, out of a justified opposition to what he calls 'the ladder of linear progress', which plots the story of evolution as a steady upward climb from the amoeba at the bottom to modern European man at the top, Gould mistakenly concludes that we must reject the idea that any course of development is more likely than any other? Hostility to any conception of historical progress or social evolution is after all rife in social theory: it shouldn't be terribly surprising that Gould might be vulnerable to the influence of this general intellectual climate.45
Dennett can't see this because he tends to see any resistance to further extending the application of Darwinian theory as a form of backsliding motivated by a commitment to 'mind-first' explanations which must ultimately fall back on the idea of a supermindthat is, of God. But a materialism that gives proper weight to the stratified character of nature can perfectly well resist any imperialistic attempt to discover the mechanisms operative at one level in all the other levels as well without running the risk of collapsing into teleology or theology.46
None of the preceding criticisms should, however, leave the reader of this review in any doubt about the quality or importance of Darwin's Dangerous Idea. The publicity material includes some words of praise for the book by the fashionable postmodernist philosopher Richard Rorty. This is strange, since Dennett is Rorty's antithesis. According to Rorty, all that philosophers do is offer more or less persuasive redescriptions of the world. But these redescriptions cannot be judged by how well or badly they capture the nature of the world. Choosing between them comes down to a matter of taste. It is hardly surprising, therefore, that Rorty believes that poets and novelists are often better and more helpful redescribers than philosophers.
For Dennett, by contrast, philosophy develops in close association with the sciences as they struggle to make better sense of the world, and thereby helps to guide our path through that world. Philosophy isn't merely dilettante essay writing, but part of the great human effort to illuminate the world and our place within it. Darwin's Dangerous Idea is invaluable reading, not merely to understand Darwin better, but also to see why philosophy is still an activity worth engaging in.
1 S Freud, The Complete Introductory Lectures on Psychoanalysis (London, 1971), pp284-285. Freud goes on to claim that his own discovery of the unconscious represented 'the third and most wounding blow' to 'human megalomania'. It was the receipt in June 1858 of a manuscript by the socialist naturalist A R Wallace in certain respects paralleling Darwin's own theory that finally prompted the latter to publish ideas he had developed much earlier: see A Desmond and J Moore, Darwin (London, 1992), p466.
2 Marx and Engels, Selected Correspondence (Moscow, 1965), p123. See also Gerratana's valuable study, 'Marx and Darwin', New Left Review, 82 (1973).
3 D C Dennett, Darwin's Dangerous Idea (London, 1995), pp63, 21.
4 Ibid, p263.
5 Socialist Worker (Chicago), 24 November 1995.
6 In fact, Dennett was a pupil of Gilbert Ryle, one of the godfathers of post-war Oxford ordinary language philosophy. In certain respects, he can be seen as developing Ryle's famous attack on what he calls 'Descartes' Myth' of 'the Ghost in the Machine', ie the mind as a set of inner, private states essentially distinct from the workings of the body: see The Concept of Mind (Harmondsworth, 1963), ch 1.
7 See D C Dennett, Brainstorms (Brighton, 1981), pp3ff for a discussion of intentional systems, and ppp110ff, where he defends 'a top-down strategy' of starting with mental functions and seeking 'to analyse these into more and more detailed systems until finally one arrives at elements familiar to the biologists' as opposed to 'a bottom-up strategy' which seeks to move from physical states to mental processes.
8 Ibid, p80. See also Dennett's discussion of homunculi (here defined as 'units with particular circumscribed competences') in Consciousness Explained (Harmondsworth, 1993), pp261-262.
9 D C Dennett, Darwin's Dangerous Idea, p206.
10 D C Dennett, Consciousness Explained, pp108, 111, 126, 228.
11 D C Dennett, Darwin's Dangerous Idea, pp205-6.
12 'Telos' is the Greek for goal.
13 D C Dennett, Brainstorms, p73.
14 C Darwin, The Origin of Species by Means of Natural Selection (Harmondsworth, 1968), pp169-170.
15 D C Dennett, Darwin's Dangerous Idea, p41. See also ibid, p343. Darwin of course derived the idea of 'the Struggle for Existence' from Thomas Malthus's theory of population, which justified social inequality on the grounds that, unless it is preserved, human populations will grow faster than the agricultural output required to support them. Darwin's version of the idea is, however, much more abstract and without these reactionary political implications. As François Jacob puts it, 'Wallace, and even more Darwin, mainly borrowed from the doctrine of Malthus the idea of an interaction between the power of reproduction and the outside forces limiting that power.' The Logic of Living Systems (London, 1974), p169. See also Gerratana, 'Marx and Darwin', op cit, pp70-75.
16 D C Dennett, Darwin's Dangerous Ideas, p65. See also ibid, ch2.
17 Ibid, p. 205. See also ibid, p69.
18 Ibid, p76, and see also ibid, chs 13 and 14. It should be noted, however, that Chomsky strongly rejects this interpretation of his views, and insists that he does believe 'language is part of "shared biological endowment" and can be studied in the manner of other biological systems' as a product of natural selection: see his letter in the New York Review of Books, 1 February 1996, p41. Steven Pinker provides a fascinating discussion of the bioligical basis of language in The Language Instinct (London, 1995).
19 Ibid, p282; see generally ibid, ch 10.
20 S J Gould, Wonderful Life (Harmondsworth, 1991), pp49-50, 289.
21 D C Dennett, Darwin's Dangerous Idea, p308.
22 Ibid, pp153-155.
23 Ibid, pp82, 63.
24 Ibid, pp177-179.
25 There is a good discussion of stratification and emergence in A Collier, Critical Realism (London, 1994), ch4.
26 D C Dennett, Darwin's Dangerous Idea, pp81-83.
27 Maybe another example of greedy reductionism is Dennett's tendency to talk of organisms as the product of design. As Colin McGinn observes, 'these are dangerous locutions for a deep-dyed Darwinian, and I am not sure that Dennett escapes the teleological pitfalls they invite. For in no literal sense is an organism designed by evolution, any more than a mountain is designed by the natural forces that permit it to exist.' 'Left-Over Life to Live', Times Literary Supplement, 24 November 1995, p1. The danger with loose talk of 'designed' organisms is shown when McGinn, one of the philosophers Dennett attacks for treating consciousness as an inexplicable mystery, exploits it as evidence that 'he cannot help thinking, in spite of knowing better, that somehow the animate world is "special"that it somehow bears the mark of intelligence and agency.'
28 R Dawkins, The Selfish Gene, (2nd edn. Oxford, 1989), pv. In assessing Dawkins's arguments two theses must be distinguishedthat the gene, rather than the organism or population of organisms, is the unit of natural selection, and that evolutionary biology can explain human social behaviour. Dawkins is, in fact, more cautious about the latter thesis, genetic reductionism proper, than about the former.
29 S Rose, L J Kamin, and R C Lewontin, Not in Our Genes (Harmondsworth, 1984), is a classic critique of sociobiology.
30 D C Dennett, Darwin's Dangerous Idea, p483, n10.
31 See R Dawkins, The Blind Watchmaker (London, 1991).
32 D C Dennett, Consciousness Explained, p202. See R Dawkins, The Selfish Gene, ch11.
33 See, for example, D C Dennett, Darwin's Dangerous Idea, pp338, 381ff, 426.
34 Ibid, pp344, 363.
35 Ibid, p33.
36 The last sentence is a summary of the conclusion of a famous essay by the great American philosopher W V O Quine, 'Two Dogmas of Empiricism', in From A Logical Point of View (New York, 1963). Darwin's Dangerous Idea is dedicated to Quine, but doesn't seem to have fully appreciated one of the crucial themes of his philosophy.
37 It has to be said, however, that Desmond and Moore tend towards the opposite error to Dennett's, in the sense that they so strongly stress Darwin's historical context that they sometimes dissolve his great breakthrough into that context, as when they write, 'Both Darwinian science and poor law society were now reformed along competitive Malthusian lines. Ruthless competition was the norm; it guaranteed the progress of life and a low-wage, high-profit capitalist society': Darwin, p265. It may well have been the case that the ideological climate of Victorian capitalism helped Darwin to formulate his theory. It doesn't follow that the theory is merely or primarily a rationalisation of the society from which it emerged. No scientific theory can be reduced to its conditions of emergence or acceptance.
38 D C Dennett, Darwin's Dangerous Idea, p345; see generally ibid, pp481-493. Interestingly, John Maynard Smith, an orthodox Darwinian biologist generally very sympathetic to Dawkins's and Dennett's approach, expresses 'uneasiness about the concept of memes': 'Genes, Memes, and Minds', New York Review of Books, 30 November 1995, p 47.
39 See, for example, his endorsement of mechanistic materialism in Brainstorms, pp 73-74, though he argues that this should not be based on 'one's prior prejudice' but rather as an inference from 'Darwins non-question-begging account of design or purpose in nature'. Natural selection is 'non-question-begging' in the sense that it explains the appearance of design in nature without presupposing the existence of a larger design and, above all, designer, ie God.
40 Marx and Engels, Collected Works V (London, 1976), p41.
41 See F Engels, 'The Part Played by Labour in the Transition from Ape to Man', in Dialectics of Nature (Moscow, 1972), pp170-183, and C Harman, 'Engels and the Origins of Human Society', International Socialism 65 (1994).
42 D C Dennett, Darwin's Dangerous Idea, pp309-312.
43 S J Gould, Wonderful Life, p323.
44 D C Dennett, Darwin's Dangerous Idea, p 312.
45 See S J Gould, Wonderful Life, pp27-45. See, for a defence of non-teleological conceptions of evolution and progress, A Callinicos, Theories and Narratives (Cambridge, 1995), chs3 and 4.
46 The idea that nature consists of a number of different levels, each with their own specific mechanisms and tendencies does not mean that it may not turn out in specific cases that one level can in fact be reduced to another. Scientific progress may sometimes take the form of such a reductionthe incorporation of chemistry within physics is an example. All a non-reductionist materialism requires is that scientific progress does not necessarily take this form.