Posted on June 14, 2011

Rule Breaker

Christopher Shea, The Chronicle of Higher Education, June 12, 2011

Patricia S. Churchland, the philosopher and neuroscientist, is sitting at a cafe on the Upper West Side, explaining the vacuousness, as she sees it, of a vast swath of contemporary moral philosophy. “I have long been interested in the origins of values,” she says, the day after lecturing on that topic at the nearby American Museum of Natural History. “But I would read contemporary ethicists and just feel very unsatisfied. It was like I couldn’t see how to tether any of it to the hard and fast. I couldn’t see how it had anything to do with evolutionary biology, which it has to do, and I couldn’t see how to attach it to the brain.”

For people familiar with Churchland’s work over the past four decades, her desire to bring the brain into the discussion will come as no surprise: She has long made the case that philosophers must take account of neuroscience in their investigations.


Churchland, professor emerita of philosophy at the University of California at San Diego, has been best known for her work on the nature of consciousness. But now, with a new book, Braintrust: What Neuroscience Tells Us About Morality (Princeton University Press), she is taking her perspective into fresh terrain: ethics. And the story she tells about morality is, as you’d expect, heavily biological, emphasizing the role of the peptide oxytocin, as well as related neurochemicals.

Oxytocin’s primary purpose appears to be in solidifying the bond between mother and infant, but Churchland argues–drawing on the work of biologists–that there are significant spillover effects: Bonds of empathy lubricated by oxytocin expand to include, first, more distant kin and then other members of one’s in-group. (Another neurochemical, aregenine vasopressin, plays a related role, as do endogenous opiates, which reinforce the appeal of cooperation by making it feel good.)

{snip}But oxytocin and its cousin-compounds ground the human capacity for empathy. (When she learned of oxytocin’s power, Churchland writes in Braintrust, she thought: “This, perhaps, Hume might accept as the germ of ‘moral sentiment.'”)

From there, culture and society begin to make their presence felt, shaping larger moral systems: tit-for-tat retaliation helps keep freeloaders and abusers of empathic understanding in line. {snip}


The biologist Sue Carter, now at the University of Illinois at Chicago, did some of the seminal work on voles, but oxytocin research on humans is now extensive as well. In a study of subjects playing a lab-based cooperative game in which the greatest benefits to two players would come if the first (the “investor”) gave a significant amount of money to the second (the “trustee”), subjects who had oxytocin sprayed into their noses donated more than twice as often as a control group, giving nearly one-fifth percent more each time.


Peter Railton, a philosophy professor at the University of Michigan at Ann Arbor, agrees. Our intuitions about how to get along with other people may have been shaped by our interactions within small groups (and between small groups). But we don’t live in small groups anymore, so we need some procedures through which we leverage our social skills into uncharted areas–and that is what the traditional academic philosophers, whom Churchland mostly rejects, work on. What are our obligations to future generations (concerning climate change, say)? What do we owe poor people on the other side of the globe (whom we might never have heard of, in our evolutionary past)?

For a more rudimentary example, consider that evolution quite likely trained us to treat “out groups” as our enemy. Philosophical argument, Railton says, can give reasons why members of the out-group are not, in fact, the malign and unusual creatures that we might instinctively think they are; we can thereby expand our circle of empathy.


Editor’s note: For more on oxytocin, including its relation to human ethnocentrism, see here and here.