EARLIER THIS YEAR, the University of California, San Diego (UCSD) held a 10-week graduate seminar on the neuroscience behind moral decision-making. It was a topic that drew its share of neuroscience and philosophy students, but it also attracted students from fields such as anthropology, computer science and political science.
This was not necessarily surprising. Leading the seminar were Patricia Churchland and Ralph Greenspan. A philosopher and neurobiologist, respectively, both have long been interested in how moral decision-making – and the mind as a whole – takes shape within the brain. As as our understanding of the brain advances, they also are finding this interest shared by people who may never before thought about their cerebral cortex or hippocampus. Many are intrigued by the prospect of understanding how the brain shapes social behavior, their areas of study, and in some cases, their professions.
“Science Made Deeply Personal”
Churchland is UC President’s Professor of Philosophy at UCSD, an Adjunct Professor at the Salk Institute, and an executive committee member of the Kavli Institute for Brain and Mind (KIBM). Beginning in the 1980s, such works as “Neurophilosophy: Toward a Unified Science of the Mind-Brain” established Churchland as a founding and driving force behind the effort to understand the interface between neuroscience and philosophy. Greenspan is the Lewis B. and Dorothy Cullman Senior Fellow at the Neuroscience Institute in La Jolla, and an associate director of the KIBM at the UCSD. A renowned researcher, his pioneering research includes using fruit flies to explore genetic and cognitive aspects of the nervous system function.
Churchland and Greenspan first met in the early 1980’s, about the same time Churchland published, with Terrence J. Sejnowski, ‘The Computational Brain.” This seminal book is credited with establishing that serious scientific approaches to understanding complex brain functions associated with the mind were both possible and relevant. Since then, a shared interest in the brain and mind has fostered a friendship between Churchland and Greemspan, and led them to see how similar their thinking is on this topic. “The truth is Pat thinks a lot like a biologist, so there isn’t a lot that we differ on,” says Greenspan.
That common ground includes the belief that to understand who we are, we must understand the neurobiological nature of decisions and choices, as well as moral motivation, self-representation and self-control. Churchland and Greenspan also recognize that many of the questions at the heart of philosophy are the same as those at the heart of neuroscience. What constitutes consciousness? What is the nature of knowledge, learning and memory? What are the roots of ethics and what can the brain tell us about how we establish and process beliefs? In short, what happens inside the brain that creates a mind, shaping what we do and who we are?
Questions like these inspired Churchland to propose a cognitive science graduate seminar called “Morality and the Social Brain.” With Churchland and Greenspan at the fore, a small team of professors would lead the discussions on the topic, including scholars in fields such as anthropology, evolutionary biology and politics. Among them was Paul Churchland, Patricia’s husband and one of the founding forces behind neurophilosophy.
It was an engaging mix of professors that met with about 50 graduate students, whose range of studies was similarly broad and diverse. “It proved to be a topic that fascinates people,” Churchland says. “Where does morality come from and why does it have the forms it has? Is there a sort of absolute set of laws written in Plato’s heaven or is it rather that as mammals, we have powerful impulses for caring for offspring that gets extended to others. Imitation, problem solving, and the capacity to interpret distress calls are also major background factors in mammalian social behavior, but how exactly do they figure in morality?”
Churchland was delighted not only by the graduate students’ range of studies, but how they engaged the subject. “This was science made deeply personal because this was about all of us. During my office hours, students would crowd into my office and argue energetically with each other. Clearly, they were deeply moved by the issues raised during the seminar.”
Greenspan recalls the same, as well as the struggle some students had in completely grasping how science could be relevant to their fields. “I remember that the political science students generally needed convincing that there was anything at all to learn from animals other than humans,” he says. “At the end of my first lecture, which was a very basic backgrounder about what we know of how genes affect behavior from relatively simple organism studies, somebody said, What does any of this have to do with morality? I said, Well, it’s funny you should ask, because my next two slides are from a lecture that I gave on neurobiological defense in the court system.”
Neuroscience in the Courtroom
In fact, as Greenspan had informed the class, this wasn’t the first time the topic had found interest beyond the usual academic audience. Two years ago, about 100 California judges travelled to the University of California, Riverside for a primer on neuroscience. Brain images had started being introduced in trials, so they were invited to a retreat aimed at deepening their understanding of the brain and technologies such as MRIs. It was also a chance to discuss some difficult questions now being raised in their courtrooms, including questions about what brain scans reveal, if anything, about personal responsibility.
Titled “Neurobiology and the Courts,” the three-day retreat was organized by the educational office of the California Administrative Office for the Court. The conference was part of an initiative to help justices understand new areas of sciences that were being introduced in their courtrooms. According to Rod Cathcart, senior attorney for the California Administrative Office of the Courts, the initiative was inaugurated in 2005 in response to DNA evidence being systematically introduced at trials. Then the MRI and its potential use as a lie detector started getting attention, so in 2007 they turned their attention to neuroscience.
During the conference, Greenspan provided a presentation on the “Genetic Basis of Neuroscience: Nature or Nurture,” while Churchland addressed “Decisions, Responsibility and the Brain.” Recalls Churchland, “They wanted to know what we are learning about the brain that tells us something about the difference between voluntary and involuntary behavior. I got the sense this came up all the time with judges and it was an extremely penetrating question. They hear arguments claiming that if the brain is a causal machine, then people can’t be held responsible for their actions. Which I regard as entirely mistaken, and the judges tended to agree.”
“When we met the judges,” says Greenspan, “they needed help dealing with expert testimony that suggested a defendant could say, for instance, that his amygdala made him do it, or maybe his genes. So a topic that was once in the realm of pure, abstract consideration was now a pressing issue in the judicial system.” He also recalls their relief at the answer. “It was one of the most interesting kinds of experiences I ever had talking to an audience. They were grappling because they really felt as though they were concerned about getting outmaneuvered in the courtroom. And one of the things we could say with a great deal of confidence is that predicting behavior is a very inexact science at best. Nothing ever makes something totally certain. Certainly none of the kinds of findings that have been made in these fields come anywhere close to giving you a firm prediction of what an individual is going to do. I think they were quite relieved to hear that.”
In fact, this is one of the many areas where Churchland and Greenspan concur. “We both agree that biology helps us understand the roots of morality and the nature of choice,” says Churchland, “but our biological natures do not dictate what we should be; choice in the social domain is not a reflex like blinking to an air puff. Because of the highly developed prefrontal structures in the human brain, we have an impressive capacity for self-control, and the developing human learns to exercise self-control. Such self-control is possible because there are a lot of neurons engaged in the executive function; but that very fact, and the fact that neural events happen at the millisecond time-scale, means that predicting exactly what someone will do is not in the cards.”
Churchland adds, “The complementary point is this: The benefits of social life are enormous; the costs are that if you violate standard moral practices, punishment – ranging from withdrawal of approval to shunning to death – may result. Those who are a threat to public safety are, by and large, those who risk punishment by the society. Just because we might be able to explain a choice does not entail that we excuse the choice. Explanation of a choice and excuses for a choice may not coincide. The factors that justify mitigating a punishment have to be carefully thought out, and mere causality of the brain is not one of exculpatory factors. The judicial system is about civic stability and safety, not about a metaphysically far-fetched capacity for uncaused choice.”
Science and Philosophy as Partners
Looking ahead, Churchland and Greenspan see a growing interest in the brain-based nature of mental processes and how adaptations of the mammalian brain shape social behavior. There also may be another benefit. Although the various specialized sciences have detached themselves from “natural” philosophy over the centuries, Greenspan and Churchland see an opportunity for science and philosophy to be closer partners in their common quest to understand the mind. If this partnership emerges, Greenspan believes it would be particularly beneficial for science. “When you talk about how the brain works above the level of a few cells, you really have to deal with some very broad and tough questions that require tough thinking. Philosophers excel at clear thinking and in analyzing.” He also sees opportunities for greater cross-fertilization between disciplines, such as a series of courses that team neuroscientists with partners from different areas of the humanities to examine concepts such as the “inner voice” of a novelist.
As for Churchland, she has already taken a major step toward establishing common ground between the two fields with her work in neurophilosophy. And through seminars such as the one at UCSD, she hopes to continue to press home the point that understanding the science behind the mind is not only important but relevant to everyone. “Everyone understands that these topics are not academic in the pejorative sense of the word, but instead are really at the center of a lot of civilized life,” she observes. “That’s why for students today, their interest in the field is not just theoretical, but also deeply practical.”