Patricia Churchland

Anydomainofscientificresearchhasitssustainingorthodoxy. Thatis, research on a problem, whether in astronomy, physics, or biology, is con- ducted against a backdrop of broadly shared assumptions. It is these as- sumptionsthatguideinquiryandprovidethecanonofwhatisreasonable-- of what "makes sense." And it is these shared assumptions that constitute a framework for the interpretation of research results. Research on the problem of how we see is likewise sustained by broadly shared assump- tions, where the current orthodoxy embraces the very general idea that the business of the visual system is to create a detailed replica of the visual world, and that it accomplishes its business via hierarchical organization and by operatingessentiallyindependently of other sensorymodalitiesas well as independently of previous learning, goals, motor planning, and motor execution.

Philosophy, in its traditional guise, addresses questions where experimental science has not yet nailed down plausible explanatory theories. Thus, the ancient Greeks pondered the nature of life, the sun, and tides, but also how we learn and make decisions. The history of science can be seen as a gradual process whereby speculative philosophy cedes intellectual space to increasingly wellgrounded experimental disciplines—first astronomy, but followed by physics, chemistry, geology, biology, archaeology, and more recently, ethology, psychology, and neuroscience. Science now encompasses plausible theories in many domains, including large-scale theories about the cosmos, life, matter, and energy. The mind’s turn has now come. The classical ‘‘mind’’ questions center on free will, the self, consciousness, how thoughts can have meaning and ‘‘aboutness,’’ and how we learn and use knowledge. All these matters interlace with questions about morality: where values come from, the roles of reason and emotion in choice, and the wherefore of responsibility and punishment. The vintage mind/body problem is a legacy of Descartes: if the mind is a completely nonphysical substance, as he thought, how can it interact causally with the physical brain? Since the weight of evidence indicates that mental processes actually are processes of the brain, Descartes’ problem has disappeared. The classical mind/ body problem has been replaced with a range of questions: what brain mechanisms explain learning, decision making, self-deception, and so on. The replacement for ‘‘the mind-body problem’’ is not a single problem; it is the vast research program of cognitive neuroscience. The dominant methodology of philosophy of mind and morals in the twentieth..

What is morality? Where does it come from? And why do most of us heed its call most of the time? In Braintrust, neurophilosophy pioneer Patricia Churchland argues that morality originates in the biology of the brain. She describes the "neurobiological platform of bonding" that, modified by evolutionary pressures and cultural values, has led to human styles of moral behavior. The result is a provocative genealogy of morals that asks us to reevaluate the priority given to religion, absolute rules, and pure reason in accounting for the basis of morality. Moral values, Churchland argues, are rooted in a behavior common to all mammals--the caring for offspring. The evolved structure, processes, and chemistry of the brain incline humans to strive not only for self-preservation but for the well-being of allied selves--first offspring, then mates, kin, and so on, in wider and wider "caring" circles. Separation and exclusion cause pain, and the company of loved ones causes pleasure; responding to feelings of social pain and pleasure, brains adjust their circuitry to local customs. In this way, caring is apportioned, conscience molded, and moral intuitions instilled. A key part of the story is oxytocin, an ancient body-and-brain molecule that, by decreasing the stress response, allows humans to develop the trust in one another necessary for the development of close-knit ties, social institutions, and morality. A major new account of what really makes us moral, Braintrust challenges us to reconsider the origins of some of our most cherished values.