STEVEN ROSE: There are I suppose a number of possible ways you can interpret what it is we're doing here this evening. One, which would be apparent to anyone who's looked at Lifelines and How the Mind Works is that Steve and I share a literary agent, a publisher, and you could make a straight-forwardly economically determinist argument that we're here to sell our books. An alternative argument would be that we write books rather as peacocks extend their tails, and that is that it's a way of demonstrating-rather than flashing our genitals at you-that we have actually rather good genes. This would in a sense be a version of the ultra-Darwinist argument.

There is another way of looking at it which explains I suspect more seriously why we're all here, and that is that the issues that we have to discuss this evening run far deeper than modern science, they go right the way back through centuries of debate, beyond Darwin, back through, certainly, a good chunk of the Judeo-Christian tradition; they are, as Susan said at the beginning, about determinism and free will, and how one understands the living world that there is around us, and it's those issues I want to discuss. But I do want to say one other thing as well-just as Steve began his talk by trying to ask why someone got on a bus. All three of the possible alternative explanations that I've given you could be right. They are not necessarily mutually incompatible. That is, as Mary Midgley puts it, we live in one world, but a big one, and we live in a world in which there are multiple possible legitimate explanations of things that we're trying to study. There are also false explanations of the things that we're trying to study, and in trying to argue for plurality, as I will do this evening, I don't want to depart for one moment from my claim about the errors of some of those views that I disagree with.

I've got two tasks here this evening: showing where I disagree with Steve Pinker, and proposing in more detail the alternative viewpoints that I take in Lifelines and The Making of Memory. Steve said there wasn't much about How the Mind Works in Lifelines, and that's perfectly true-I did write about it in The Making of Memory, and Lifelines has a different task. I'm going to try and interweave these two. And again, let me pause for a moment also to say what I'm doing. Steve makes in his book, and he made at the end of what he had to say there, what I can only describe as a personal political attack concerning the implications of some of the things that I've written about.

I do feel very strongly about issues of what I've called neuro-genetic determinism, and the political and social implications of some of the ideas that are floating around within genetics at the moment. It wasn't intention to discuss them this evening. I'm going to try not to be riled by what he said, but to put it slightly to one side. I am here essentially as a practicing biologist. I'm here for the same reasons I wrote Lifelines. I've spent my research life studying real living animals, and the workings of their brains, and worrying about the relevance of what I've observed to my own lived human experience. And like other biologists, I find the rather abstract theorizing of those who spend more time with their computers than with living organisms a bit distressing.

So my case is rooted in understanding how real brains and living processes in general work. I'm going to focus on Steve's main theses and show how Lifeline's approach gives us a very different understanding of them. Steve defines mind-he did it now and he did it before, as the information-processing property of the brain. The mind he talks about isn't a coherent unity; it's an interacting community of distinct modules, each specialized for a particular function. It's evolved, as he explained to us, as a device for enhancing human survival, and reproductive success, according to ultra-Darwinian principles. Now as Susan said at the beginning, no biologist is going to have any problems with the claims that we humans-all of our attributes, behavioral as well as physical have evolved, and they've been honed to their present form, at least in good part, by the workings of natural selection. The devil as usual is in the details. Steve, like me, quotes the evolutionary biologist, Theodesius Dobzhansky - "Nothing in biology makes sense except in the light of evolution".

I have a crucial emendation: "Nothing in biology makes sense except in the light of history." That is, evolutionary history, developmental history, social history, the history of our science itself. It was the last clause there that he took particular exception to; I'm not going to try and defend it this evening, I've got other tasks in mind. If he wishes to discount the evidence of philosophers, sociologists and economists who've studied scientific processes over the last 20 or 30 years he's at liberty to do so, but I suspect he's talking outside his terrain of knowledge.

Let me deal however with the little matter of mind. Steve's mind is a machine, a sort of abstraction that computer engineers program when exploring artificial intelligence. The megaphone diplomacy of the dust jacket of his book proclaims, "this is the best book ever written on the human mind." This is, I think, the vulgar dismissal of several thousand years of human science and philosophy. His mind, like a computer, deals with information. By contrast-and this is what I want to emphasize-real brains transform dead information into living meaning-the making sense of the world around us. It's a meaning which is given to sensory inputs by the working of the brain. It's based on experience, and it's provided through its evolutionary and developmental history. Let me give you an example, from Steve's own book. A footprint, he says, carries information. But the information, without an observer to give that information meaning, is strictly dead. Think for example of Robinson Crusoe on his island; finding a footprint on the sandy shore, the multiple meanings he gives that particular footprint- fear, anxiety, excitement, interpretation based on human history, and so on. Culture, history, personal experience-they all feed into that meaning.

Which brings me to another crucial point, that I emphasize again and again in Lifelines-that is finding the right level of explanation for any phenomenon, the fundamental point of scientific method-and here I mean not just natural science, but all science. Steve's agenda is grandiose, taking on in his last chapter the meaning of life, but his answer is I think slightly less relevant than 42. Take human love, for example-Steven explains love, and he did so again on Start the Week-as resulting from the shared interest of partners in the genes of their offspring. No possibility here for homosexual, same-sex love, no possibility here for the love which goes between-for people who are not-and infants who are not one's own genetic offspring, and so on. It's just this impoverishment of thought, which occurs again and again in the ways in which these terms are used, by people of Steve's persuasion in this context, that I find, both as a human and as a biologist, distinctly troublesome. Sure, as a neuro-scientist I can talk about the firing of cells in the hypothalamus; hormone surges, cortical representations, all the things that go on in the brain when one's in love. Neither those, nor the genes, tell us anything about the feeling of what it's like to be in love-what it means to be a person in love, two people in love, and their interactions.

The fact is that Steve's mind isn't a unified, coherent center of conscious thought, or emotion, or action-it's not a product of the inextricable interplay of biology and culture. It's a sort of Swiss army knife-it's modular. It's his analogy, not mine-it's a compressed miracle of pull-out devices-if not for taking stones from horses' hooves, then for seeing stereoscopically, or speaking grammatically. As Jerry Fodor points out, in the current issue of the London Review of Books-and it's surprising, because Jerry ought to have been one of Steve's heroes-nothing in this assemblage of independent modules enables us to understand what it means to be a person, with a conscious RIS. Neither cognitive neuroscience, Steve's area, or mine, neurobiology, can yet begin to approach that sort of problem. Each module, he argues, is evolved separately, and operates autonomously, although in the interests of the genes that created it. The modules spring fully formed, and unmediated from their genes, each presumably containing a miniature blueprint for a particular implement within the Swiss army knife. And here we come to the core of the argument, which Steve takes over holus-bolus from Richard Dawkins. For all the various complex aspects of being an organism, being a person, are merely ways in which our selfish genes program the lumbering robots which constitute us, to serve their, that is the genes', interest. This is precisely the view which Lifeline opposes. Just as Steve's mind has little to do with real brains, his genes have little to do with real strands of DNA, this is what I work with in the lab-they're theoretical entities. Real humans, like all other living organisms, grow and develop. They create themselves through the dynamic interplay of DNA and the cellular orchestra in which it's embedded, and the cells, with their external environment. Modularity, if it exists, emerges dynamically. Now I want to insist, despite what he said, that living organisms exist in four dimensions-three of space and one of time-and they can't be read off from the single dimension of DNA. Organisms and minds aren't empty phenotypes related one to one, with particular patterns of genes. Our lives form a developmental trajectory, or lifeline, and are stabilized by the operation of what I call homeodynamics-they're principles I discuss in the book. This trajectory isn't determined by our genes, nor is it partitioned into neatly dichotomous categories called nature and nurture. Rather, it's what I call an autopoetic process-he doesn't like the term- it's shaped, I say, by the interplay of specificity and plasticity. Insofar as any aspect of life can be said to be in the genes, our genes provide the capacity for specificity, a lifeline relatively impervious to developmental and environmental buffering; and also plasticity, the ability to respond appropriately to unpredictable environmental contingencies; that is, to experience. The crucial thing is this. All living organisms have simultaneously both to be and to become. Take a newborn baby, for example. The baby is born with a sucking reflex. A little while later, the baby develops into a child which doesn't suckle, it chews its food. Chewing involves a totally different set of muscles and operations than suckling. To develop, the newborn baby has both to be competent as a suckler, and to transform itself into a chewer. And it's that dynamic, that self-construction, which is completely lost in the abstract understanding of genes and the behaviors they control. And what I fear is that the reductionist and simplistic approach which Steve has offered us freezes life. In attempting to capture its being it loses becoming. It turns process into reified objects. Organisms are open systems-they're far from dynamic equilibrium. Continuity is provided by a constant flow of energy through them. Every molecule, every organelle, every cell, is in a constant state of flux. Formation, transformation, renewal. Dynamic stability of form persists, though every constituent of that form, every molecule, has been replaced. And the stability depends on the capacity of complex interacting systems to self-organize. In this view of living systems, there are no master molecules, no naked replicators controlling cellular events within the screened-off tranquillity of a nuclear board room. Genes, lengths of DNA, are engaged in a continual metabolic interchange with other cellular components. A molecular democracy constrained by cellular organization, and the needs of the organism.

And now finally I come to the question of evolution, and above all evolutionary psychology, and Steve's famous simplistic reverse engineering, by which we're to understand How the Mind Works. The trouble with reverse engineering the mind, is that by contrast with human artifacts, when we're told the story about how it might have arisen, we've simply no way of testing it out. Evolutionary stories, almost by definition just-so stories of the sort Rudyard Kipling provided when he explained how the elephant got its trunk-I'm quite sure that we could find an evolutionary explanation why so many of the men writing in this area are called either Steve or Richard. It doesn't actually, however, help us forward at all. Now although Steve Pinker is aware of the fallacy of assuming that every biological feature is adaptively designed, through infinitely flexible and all-wise natural selection, he frequently ignores his own caveats. Thus at one point he discusses the tortuous route that the human seminal ducts take from the testes up through the body and across the ureter to the penis, and explains this on the well-known but Kiplingesque grounds that "the testes of our reptilian ancestors were inside their bodies. The bodies of mammals are too hot for the production of sperm, so the testes gradually descended into a scrotum." If Superman is so clever, why does he wear his underpants outside his trousers? Natural selection, if so clever, why don't they evolve sperm which can survive at higher temperatures, rather than the ungainly and hazardous physical control system that was adopted? Almost certainly it's either because of contingency, the chance events that another Steve, Steve Gould, evoked in his rich account of evolutionary process in his book Wonderful Life, or because there are other design constraints on what can or cannot be achieved by natural selection. That is, natural selection doesn't work unrestrictedly, a la carte, but is limited to a table d'hote choice of only a limited range of options. We don't have to find adaptations for everything. Again, the alternative viewpoints in Lifelines: organisms are in constant interaction with their environments. Organisms actively select and transform their environments, just as environments select and transform organisms. I don't just mean humans, I mean any living system. Even a single-celled organism chooses, changes, transforms its environment in particular ways. Evolutionary change occurs as a result of the continued interception of lifeline trajectories with changing environments. Such change occurs at multiple-levels, from the molecular to the species. That is, the individual gene, selfish or not, is not the only site of evolutionary change. Natural selection is the prime, but not the only mechanism of this change. There are constraints on selective processes. Not all change is adaptive, as Steve has agreed. Some may be contingent, accidental, accidents of history and essentially neutral in its effect. And because of the extent to which organisms select and modify environments, they're not simply the passive victims of selective processes, but play an active part in their-in our-own destiny.

Third, evolution isn't indefinitely flexible. Not all that's possible is achievable. This is partly because living processes are in their essence only comprehensible in historical context, and there are no such things in life as de novo engineering solutions to problems. The material for evolutionary change is restricted to what's currently present. Opening certain pathways closes others. Further, there are physical and chemical constraints on the structural possibilities available through evolution, >from the rates of diffusion of dissolved gases, to the mechanical properties of the calcium phosphate of bones, or the cellulose walls of plant cells. These limit cell size, body volumes, rates of movements, patterns of behavior, and they can't be bypassed by any amount of genetic tinkering. Let's be clear: humans can't be turned into angels by grafting onto us a genetic program for wings; it's nothing to do with virtue, but because no wing bone and muscle structure could achieve the lift to enable us to fly. What we do possess, courtesy of our evolutionary history, is the cerebral, social and technical facilities for every single one of us to construct societies and machines, enabling all of us to fly, without the need for genetic change at all. Is this dynamic which is so lacking from what used to be called sociobiology and is now called evolutionary psychology, to which Steve has become such an enthusiastic convert. He argues his mind modules evolved to suit humanity's Stone Age existence, to help our ancestors survive as social animals, by lying, swindling convincingly, but by being able to detect lying and swindling in our neighbors, by murdering our step-children but protecting our genetic kin. The Stone Age they portray has I always feel something of the Flintstone quality about it; that is current U.S. suburban mores transported into the dim past. Further, for reasons that are completely unclear to me, evolution of brains and behavior apparently stopped in the Stone Age, though elsewhere Steve points out quite rightly the time that's elapsed since then would be quite adequate for quite dramatic brain changes. The point is that once we accept that the key to understanding living processes isn't just evolution but history, and abandon the extraordinarily static world-view of ultra-Darwinism, then all this romanticized Stone Age nonsense falls into proper perspective. It's surely precisely the unique properties of human biology that have enabled us to evolve the minds and societies that we inhabit today. But in evolving these societies our minds and brains too have been profoundly changed.

Let me give one last biological example. The human cerebral cortex has evolved from structures which in our reptilian ancestors were used for odor detection. On the Pinker model of the world, this would mean that we think by smelling. We don't. Old structures develop new functions as part of the lifeline trajectories of individuals, societies, and species.

Now finally, what I find very odd about all this macho evolutionary talk, with its wild speculative finale on the meaning of life, is the extent to which in the last analysis it wants to have its cake and eat it. We are, evolutionary psychology argues, mainly the deterministically driven products of our selfish genes and their sole interest, that of replication. All our deepest desires and emotions, our abject selfish failures, as well as our most selfless ambitions to create a more beautiful world, these are all simply shadow-play. Yet at times Steve, quite rightly, like Richard Dawkins and others, recoils from this bleak vision. He is in some unexplained way free; as he puts it, very clearly, in the book, if his genes don't like what he does, they can go jump in the lake. Now, what I find very puzzling is to understand where this freedom comes from. Does it fall from the sky? Are we suddenly to invoke some new deity to enable him to escape from the deterministic trap into which he's painted himself? I simply can't go with this Cartesian split. This is why I want to claim that I'm talking a deeper and a richer materialism than Steve is in his account. It's a materialism that takes account of dynamism, and isn't statically frozen into the past. And it's this richer understanding of biology, the mechanistically driven approach, which helps us to understand that for us, like all living creatures, the future is radically unpredictable. And this is the take-home message, not any of the political overtones or undertones which Steve has chosen to read into it, which is in Lifelines. I have written political books, or books which have attempted to discuss politics; Lifelines doesn't. It's an attempt to discuss biological processes. An attempt to help us understand how we need to take on board the reductionist triumphs of biology of the last century, which he has so eloquently described; but also recognize that in order to understand living processes in their depth and richness, these triumphs of genetics, of biochemistry, of the study of human behavior of the last decades, need to be set into a much richer and deeper context. It's that context which I insist the new biology ought to be about. And what it implies above all, so far as humans are concerned, is that we have the ability to construct our own futures, though in circumstances not of our own choosing. This ability is provided by our genes as part of the living dynamic processes in which they are embedded. And in the final words of Lifelines, it is therefore our biology which makes us free. Thank you.