A neurobiologist and a philosopher adapt the perspectives of their disciplines to develop a unified account of morality.

Is the human brain sufficient to account for ethical behavior? Throughout history, the response to this question has been a resounding “No!” In line with the opening quotation, Kant and most other great thinkers have concluded that a “naturalistic” ethic is impossible. Morality is not innate; people left on their own would be selfish, overriding the interests of others. Society must be safeguarded by rules or norms imposed by a higher authority. For this authority, the monarch or pope is a typical surrogate, but only “by the grace of God.” To account for kindness, charity, and other social virtues, people have looked to a Creator, a Guiding Hand, a supernatural inspiration. To explain the unknown—the sun’s progress across the sky, thunder and lightning, the vagaries of the human heart—people have populated the world with spirits (but have left the spirits themselves arbitrary and unexplained, kicking the problem upstairs). Similarly, ethical behavior and altruism, also not readily explained, have been ascribed to intervention by these spirits rather than to human nature alone. Thus the distinction between matters temporal and spiritual, body and soul, has always been pivotal to religion. In 1656, Benedict Spinoza, the philosophical genius and forerunner of a naturalistic ethic, was expelled from the Jewish community in Amsterdam for doubting the body-soul distinction. For once, Jews and Christians, Catholics and Calvinists, all agreed. Spinoza’s work landed on the Catholic Church’s Index of Prohibited Books. Lately, the Vatican has conceded that the body evolved, but still firmly denies evolution to the soul. As science has kept clarifying what previously seemed mysterious, the supernatural has been crowded into an ever-smaller corner of the conceptual playing field. Life itself has been demystified. Vitalism, the élan vital, what the philosopher Henri Bergson called “life spirit,” has yielded to a mundane explanation of living things in terms of organic chemistry. While it was dominated by the Church, natural philosophy treated science and religion as compatible, if not mutually supportive; now it has fragmented into parallel and largely non-communicating branches. Today, natural scientists do not, as a rule, have much use for philosophy. In fact, scientists typically perceive themselves to be unencumbered by theoretical preconceptions, unbiased observers of the facts. Philosophers know better how hard it is to override the dead weight of cumulative cultural preconceptions. The “atheoretical” scientist is usually only one who has failed to articulate his theoretical guidelines, and therefore does not realize how much they constrain his thinking. Although scientists rarely think so (if they think about them at all), philosophers do have a role to play in scientific progress, specifically in neuroscience. After William James at the turn of the previous century, who famously applied psychological findings to his philosophy of mind, there was a long lapse, during which philosophers of mind were more critical of science than constructive. But now the fields approach again, at least within the English-speaking (British and American) tradition. Philosophers of mind regularly use findings from neuroscience to explain, illustrate, and buttress their theoretical constructs. This could foreshadow a development in neuroscience that is taken as a matter of course in the more mature science of physics. Theoretical physicists and experimental physicists continually interact to the advantage of progress in their science. “Neurophilosophers” may anticipate a new category of “theoretical neuroscientists.” The dialogue in What Makes Us Think may be regarded in this light. The book is a translation of a series of conversations between a neuroscientist and a philosopher—a step toward reinventing a secular natural philosophy. FROM BRAIN BIOLOGY: A UNIVERSAL ETHIC? Two world-class French scholars, a neurobiologist and a philosopher of the phenomenalist school, meet toward a common goal: to adapt the perspectives of their disciplines, their discourses, to develop a unified naturalistic account of morality. They aspire to an ethic that, deriving solely from the biology of the human brain, owes nothing to traditional beliefs. They seek a resounding “Yes!” to our opening question. Such a “naturalized” ethic, surmounting the barriers of race, gender, or culture, appeals to the universal among humans by transcending divisive, conflicting, arbitrary views of the world. Indeed, it is precisely contrary to the current norm among social scientists (Ricoeur, the philosopher, not excepted) of emphasizing the plurality of ethics and rejecting any universal standard. Ironically, this pluralistic view is in ascendancy just as indigenous cultures are being homogenized by a Western cultural invasion. Regardless, the authors take as their goal to fashion tools “for ethical innovation in the selection and transmission of the norms of moral life". Such tools would be concepts that justify a universal ethic without appeal to the supernatural. Specifically, they would make peace prevail over war and violence. Jean-Pierre Changeux, the neurobiologist, has made seminal discoveries about the molecular switches that control communication across the synapse—the junction between nerve cells across which chemical neurotransmitters ferry stimulation. But beyond molecular biology, this discussion showcases Changeux’s grasp of a range of levels of neuroscientific analysis. The neurosciences today have little in common beyond their shared subject—the nervous system approached experimentally— so there is no reason a neurochemist should appreciate neuropsychology, for instance. Changeux, however, has extended his interests to include the construction of computer models that simulate the brain in some of its activities and the study of people in the act of thinking by imaging the brain to identify the active areas. Unlike most neuroscientists, he has the command of philosophy, history, and aesthetics needed to meet the philosopher on his own ground. Though Changeux protests that he is not a materialist, he is one—along with every other living neuroscientist who has seriously considered the matter. For him, man is nothing but a material object, something with only physical properties. Jean Ricoeur, the philosopher, expounds philosophic traditions dominant in Europe but rare in the British and American world of philosophy: phenomenology and hermeneutics. Following Edmund Husserl, phenomenologists focus on the subjective, on “lived” experience. They analyze hopes and fears, delights and disgusts, as people experience them. Hermeneutics inquires into the nature of meaning. Martin Heidegger was a famous exponent of this philosophy, which closely analyzes spoken and written texts but views them not as expressions of the author but as indications of the prevalent discourse of a given time and place. Heidegger objected to the “narrow realism” of science, which he saw as an “emasculation of the spirit.” Ricoeur has extended this analysis into the area of ethics and the rules and norms of the law. He sees himself ultimately as Spinoza’s heir, but Spinoza might not have seen it that way. According to the latter, “Man’s judgment is a function of the disposition of the brain,” but in Ricoeur’s discussion with Changeux, he strenuously opposes any such “subpersonal” approach. Neuroscience itself, the very idea of a system of nerve cells, says Ricoeur, is a social construct; the experience of the whole person cannot be deduced from scrutinizing his components. Ricoeur takes a role in this discussion unlike that any English-speaking philosopher of mind might have taken. An American compendium of discussions in philosophy of mind published in 1997 (The Nature of Consciousness, by Ned Block, et al.) illustrates the gulf between English-speaking and European philosophy: in 50 contributions spanning 800 pages, Husserl, Heidegger, Ricoeur, phenomenology, and hermeneutics are never even mentioned. In contrast, neuroscience spans both English-speaking and continental cultures. Neuroscientists worldwide agree on goals and means, and many English and American neurobiologists would have presented their field much as Changeux does. As a European philosopher, Ricoeur is exceptional in participating in, not confronting, the discourse of neuroscience. By the same token, Changeux is untypical in his openness to considerations of culture and his literacy in the humanities. Nonetheless, the dialogue is pitched at an awkward level, one too technical and jargon-riddled for the educated general reader but too sketchy and abbreviated for the expert. (This was probably unavoidable, given the huge territory traversed as the discussion races from molecule to mind.) Yet their conversation is graceful and organized. The translation is unobtrusively readable, although the title misses the main point of the dialogue. A SPIRALING DUET The debate begins at the individual nerve cell and proceeds through the levels of neural organization. Changeux would “develop a panorama of neuroscience from cell to cerebrum,” seeking to extrapolate to higher mental function and, he hopes, to ethics. As their dialogue unfolds, elegantly phrased but not entirely free of the lingo of their respective fields, the debaters engage in a spiraling duet. The neurobiologist takes the lead, the philosopher falling back only to return again at the next level of neural organization. Rejecting the supernatural, Changeux believes that knowledge of the brain is fundamental to any account of moral action—although the bulk of the discussion focuses on lower levels of the brain, which are irrelevant to morality but about which more is known. Ricoeur provides a cautionary counterpoint, emphasizing what cannot yet be accounted for by current neuroscience. He invokes the fabric of experience, “what it is like,” and the meaningfulness of our perceptions, which have no clear neuroscience counterpart. Intermittently, he worries about an incipient “hegemony” by the neurosciences, and promotes his phenomenological philosophy as the equal of neuroscience (whatever that means). He claims that “these discourses represent heterogeneous perspectives [that] cannot be reduced to each other or derived from each other.” More plainly stated, he feels that the enterprise of fashioning a common discourse really means subjugating his field to Changeux’s and that this will (or should) fail. Still, he persists in a discussion that contemplates just such a subjugation. Confronted by yet more information from Changeux, he asks again and again, in different words, “Does the new knowledge about the cortex add to what I already know through direct bodily experience?” (“I have my doubts”). Again and again, Changeux defers an answer. Taking no prisoners, Ricoeur also will have nothing to do with clinical examples from neuropsychology, the science of the effects of brain damage on behavior and the mind, usually regarded as a major source of insight into the workings of the brain. He dismisses the brain-damaged patient’s experience as atypical—and uninformative about normal (“felicitous”) functioning. Foiled, the neurobiologist moves on to the thought processes of normal (presumably felicitous) individuals. He tries mightily to persuade the philosopher that images of the brain, obtained by PET and fMRI as people think and feel in different ways, offer us new, direct, and objective insight into lived experience. When one perceives an object, the cerebral visual area may exhibit a pattern of activation of somewhat similar shape. Solving a problem from someone else’s point of view activates areas of the brain that remain quiescent when one solves it for oneself alone. The philosopher is not persuaded by this mental geography. I never doubted that all this goes on in the brain, he implies. But knowing where does not teach us how the brain does it, and certainly not what the person thinks or feels while doing it. Finally, Ricoeur can no longer contain himself: “[In] one’s heart of hearts...in which one speaks to oneself...you will never succeed in explaining your science!” (Never say never, Changeux in effect cheerily responds.) Curiously, though he rejects the supernatural, Ricoeur never frankly acknowledges that “lived experience” is brain action. But where else might the “heart of hearts” be located? Changeux, conventionally sticking to what can be objectively observed, does not take up the challenge of situating the subjective where it belongs—in the brain as an object of science. In the following representative excerpt, Ricoeur has just rhapsodized about the “inspirational”: Changeux: What a lot of bric-a-brac! Madness, aesthetics, the Judeo-Christian tradition–this confirms my doubts about your third level of meaning. What’s more, this level doesn’t seem to take into account a fundamental datum, namely evolution. Ricoeur: Evolution surely gives rise to a progressive enriching of experience. I will even grant you that our brain has developed in such a way that it is capable of giving us access to an experience as powerful as the folly that Erasmus famously praised. Changeux: I think you introduce a sort of finality, or purpose, in evolution Ricoeur: No, it is simply that I stand in a broad phenomenological tradition, and I don’t want to have you disfiguring it because you haven’t yet found its equivalent. Changeux: I don’t disfigure it. I simply wish to proceed with the caution of a scientist who tries to avoid appealing to immaterial forces or to ambiguous principles that seem purely imaginary. Ricoeur: But human experience isn’t only scientific. Changeux: Never in my life have I considered human experience as “only scientific.” So it goes. Notwithstanding roadblocks at every pass, they sweep on to the next level, and the next, and ultimately to the level of concepts and beliefs (at which, however, Changeux is less at home than lower down). It is at the conceptual level that they seek, but do not find, common ground for a naturalistic morality, one disencumbered of supernatural baggage. There was really no need to consider the lower levels of neural organization, given the stated purpose of the exercise. A romantic appeal by Changeux to artistic endeavor as a nonsectarian substitute for religious belief leads the reader to a poetic but unconvincingly optimistic conclusion, as the dialogue peters out in a haze of undifferentiated goodwill. I wish that I could report that they attained their goal. They did not, of course, and could not—and knew that they would not. Their discourses remain unreconciled, their differences unresolved, and therefore the question of a universal ethic explored but not settled. Still, there is much to learn from their attempt. COUNTING ON CULTURAL TRANSMISSION The impasse of two allegedly disparate and irreconcilable discourses—one in terms of observation by an investigator, the other in terms of subjective experience (private and unobservable)—threads its way through the whole discussion. Yet there is a way to resolve the impasse. The discussants may not be comfortable with this solution, but at times they come close to it: Ricoeur: Can mental experience be identified with the observed neural activity? Changeux: For me this poses no problem. In fact, it represents a very important conceptual advance in my field. This exchange skirts an increasingly influential theory of brain function, to which I adhere: Identity Theory. This theory proposes that the objectively observable, dynamic activity of the brain and the subjective play of experience both not only depend on brain and brain alone (which few would dispute nowadays) but are identical—two manifestations of the very same thing. Experience is the action of the brain, the chatter of the neurons. Subjective awareness is not a product of the brain, a different aspect, but the functioning of the brain itself. If so, the two discourses are truly one and both scholars are discussing the same thing. But, for reasons that they deem too obvious to require explanation, they disdain American “eliminativists” who hold such views. As a result, they never properly come to grips with the implications for their quest of the identity of experience and the activity of the brain. What factors shape the evolution of the mind, and can they be influenced? They are genetic, epigenetic, and cultural; each operates on a different time scale. The “genetic envelope” determines overall organization. Within its confines, the neurons compete and distribute in uniquely patterned circuits. This is the epigenetic contribution to the neural architecture. The human genetic endowment—our genome—ultimately makes possible our level of thought, but the genome is thought to have changed little in the past hundred million years. The explosive evolution of Homo sapiens over as little as five million years since an ancestor that we shared with the great apes suggests the influence of a faster process, epigenesis. The acceleration of human evolution at doubling and redoubling speeds over the last 3,000 years suggests the influence of ultrafast cultural transmission. What are these three modes of evolution, and how do they interact? There are a hundred billion neurons, with many trillions of interconnections, in the human brain, which accounts for about 20 percent of the body’s overall energy consumption. So expensive an organ must have needed all these units to function optimally or it would have succumbed to natural selection. The human genome consists of perhaps only 50,000-80,000 genes (99 percent of which we share with chimpanzees). Although up to half of the human genome is devoted to shaping the nervous system, these genes are still far too few to determine the detailed architecture of the brain. They can only be signposts directing neuron populations in specific directions, leaving the details of the resulting network to chance and to sometimes idiosyncratic interaction with the environment. Epigenesis enters the picture here, making for individual variation and so offering scope for novel attributes to emerge. Development progresses along paths predetermined by genes; as it does, however, it reaches many choice points, at which its direction is a matter of probabilities. The variations among individuals that result from the different paths taken are termed “epigenetic.” Because of epigenesis, even identical twins, with exactly the same genes, differ notably in their brain architecture. Ricoeur and Changeux view themselves as taking some early steps in generating ideas that can sway people toward the ethical alternative when they make choices, regardless of the circumstances. To do this, the two thinkers know that they must influence cultural evolution, presumably by the use of language, genetics and epigenesis being out of reach. In The Descent of Man, Charles Darwin remarked on analogies in the evolution of species and of language. “Survival or preservation of certain favored words in the struggle for existence is natural selection.” In the case of language, transmission is not genetic but cultural. Richard Dawkins has generalized this point, coining the word meme to denote an idea that competes with rival ideas for control of people’s minds. The meme is a “unit of cultural transmission.” According to Dawkins, memes are “achieving evolutionary change at a rate which leaves the old gene panting far behind.” Memes are supposed to be independent agents, analogous to genes in their selfishness, and the brain their helpless host. But it is brains that fashion and communicate memes, and only those memes succeed for which the receiving brain happens to be ready. If one wants timely positive changes in human nature (say, from aggressive and acquisitive to cooperative and altruistic), one must influence cultural rather than genetic or epigenetic transmission. Of course, it is fundamental to the theory of biological evolution that it is unsupervised. There is no Designer, no Guiding Hand. But human agents guide cultural evolution. No doubt this is what makes cultural evolution more economical and infinitely faster than genetic evolution. Through most of modern history, cultural evolution via ideas about the good life has been under church control. Now that control is passing to the community and, in particular, to intellectuals. TIMELY, EFFECTIVE ALTRUISTIC MEMES One promising biological vehicle for positive change is the innate ability of human beings to empathize with, and even to experience, in part, another’s distress. This presupposes a “theory of mind,” the capacity to attribute to others a mental life similar to one’s own. By about three years of age, children can see the world from another’s perspective—that person’s intentions, beliefs, and desires. The attribution of feelings to other people may be limited, however, by our culture. Just being able to attribute feelings to others, and to empathize with them, does not mean that we will. In a given culture, disfavored groups may be denied feelings, as Shylock memorably complains in Shakespeare’s Merchant of Venice: “Hath not a Jew eyes?...” Their feelings may be ignored or trivialized as “childlike.” Extending the attribution of feelings, and as a consequence our empathy, to groups out of favor would contribute to the truly universal “new ethic,” rooted in biology, to which Changeux and Ricoeur aspire. The biological basis for such a position appears to reside in the prefrontal cortex, available to everyone in whom this structure is intact. The issue is, to whom do people actually apply their ability to empathize? That is much influenced by cultural factors. Generalizing the attribution of feelings to all of mankind awaits a suite of truly effective altruistic memes. Spinoza did not think that self-interest and virtuous behavior are necessarily antithetical. On the contrary: “The [effort] to preserve oneself is the primary and sole basis of virtue.” Such distinguished endorsement legitimizes the goal of the Changeux-Ricouer dialogue. For self-seeking also to join the common good would obviously be desirable. Indeed, as the bittersweet century that has just elapsed has demonstrated, such a convergence of interests may be crucial for our survival as a species. Changeux cites Auguste Comte, who wrote: “There is no reason to think that the most complex phenomena of living bodies—social phenomena—are different in kind than the simplest phenomena of natural bodies.” Failing religious belief, Comte’s radical materialism may be the last best hope for survival, let alone perfectibility, of our species. A SLUR ON WOLVES In a foreword to What Makes Us Think? the authors encourage the reader to enter their debate as a partner. I grasp this opportunity to comment that a biological account of selfless and altruistic behavior is incomplete without an account of their opposites. Both the constructive and the destructive are deeply rooted in our biology. In a way, this echoes much in animal behavior, but the immense scope and sweep of both constructive and destructive forces are uniquely human. Therein lies the problem. The propensity of humans to wreak gratuitous havoc, no less than to cherish and protect, has been strenuously addressed by moralists within and outside the great religions. But from the vantage point of the new millennium, the efforts of the religions, as well as those of secular philosophies such as Marxism, seem incomplete and ineffectual. Encapsulating in a sentence the distress of the faithful through the ages, the English poet and Jesuit priest Gerard Manley Hopkins asked God: “Why do sinners’ ways prosper, /and why does disappointment all that I endeavor end?” No satisfactory answer is on record. The naturalization of cooperation and nurturing that Changeux and Ricoeur energetically pursue must be understood in the context of its converse: the naturalization of greed and aggression. Both sets of attributes are spectacularly developed in humans, as compared to all other animals. Why? Many species, including our primate cousins, nurture their kin, attack prey, evade predators, and repel territorial invaders and rivals for mates. Their aggressive drive and nurturing drive are tightly “wired” in their brains, so as to be elicited only under specific circumstances—and then only to the extent needed. Animals nurture their kin only. Predators kill to survive, but go no further. The lioness does not gratuitously slaughter the herd and let it rot. When two wolves struggle for dominance, one prevails, but when the rival signals submission, he is permitted to live. Stating the situation neurobiologically, the drive (aggressive, defensive, nurturing) is tightly wired to certain objectives, and suspended when they are attained. The human repertoire of drives is not fundamentally different. Our cognitive equipment in the cerebrum has explosively expanded from that of other behaviorally developed mammals, but our limbic cortex—the source of motivations and emotions that drive all behaviors—has not. What has radically expanded is the sheer range of the contingencies that activate our motivations and emotions. The grim remark Homo hominem lupus—“man is as a wolf to man”—is a slur on wolves. We need the ethic, not animals. LIMBIC DRIVES THAT RUN AMOK Look more closely. Humans have at their disposal a far greater range of specialized cognitive modules, or specialized cortical areas, than even their closest primate kin. Paul Rozin has pointed out that we also differ in the ability of our specialized cerebral areas to share their capabilities with one another. He cites “the extension of a mental capacity that is highly specialized for solving one type of problem to another type of problem.” I would extend this to include the human repertoire of limbic cortical drives. In humans, these drives are no longer tightly matched with limited goals and specific ends but are potentially applicable, under diverse conditions, to an enormous range of different ends. Thus nurturing, not limited to the kin group, for some extends throughout humanity (as rendered magnificently in the Latin epigram, nihil humani a me alienum puto: “nothing that is human is foreign to me”). Acquisitiveness, and the aggression that fuels it, can flower into unlimited greed for resources, far in excess of what the individual could need or use. Dominance displays escalate into power plays that, in the extreme, may even run amok in genocide. Nor does this apply only to developed Western culture (though we have far more effective means of carrying it out). Native American tribes (Iroquois and Huron) eradicated each other with no less ferocity, and by no means only to assure their personal survival, than did and do the inheritors of Western civilization (Serbs and Croats). Thus theory of mind is the impetus for empathy, sympathy, and mutual assistance, but ironically (though this has escaped comment) also must inspire the sadist and torturer. In short, the blip on the human genome to which Rozin pointed, the opening up of the specialized “modules” to one another, though no doubt selected by evolution for some long-ago adaptive advantage, generalizes wildly. Truly, the genie is out of the modular bottle. The very book I am reviewing opens up hitherto distinct, ostensibly irreconcilable concepts to one another. There should be a way to reroute the contingencies under which emotions seize control of our actions. The means of rerouting would be cultural influence. Biology creates dispositions; circumstances transform dispositions into actions; but culture can intervene by controlling how we interpret those circumstances. Culture arises from the voluntary interactions of humans and can be voluntarily modified. After all, through our culture we are able to identify a Guiding Hand. It is our own.

ethics, bioethics, philosophy, philosopher, brain, morality,