An interview with Michael Gazzaniga
Michael Gazzaniga believes in a "brain-based philosophy of life." Perhaps that's not surprising—he is, after all, a professor of neuroscience and director of the Center for Cognitive Neuroscience at Dartmouth College. It is remarkable, however, that he's willing to tackle some of today's most contentious social, political and scientific issues, armed only with a curious mind and the knowledge gained from years of experience studying the brain. In his new book, The Ethical Brain (Dana Press, 2005), he weighs in on stem cell research, euthanasia, the criminal justice system and much more, bringing to bear recent developments in neuroscience. He also discusses his experiences as a member of the President's Council on Bioethics.
Gazzaniga's brief but ambitious book is centered on the idea that "you are your brain." So, for example, he argues that "a fertilized egg, a clump of cells with no brain, is hardly deserving of the same moral status we confer on the newborn child or the functioning adult." Neuroscience also has implications for understanding religious faith, says Gazzaniga, suggesting that "religiosity could have an organic basis within the normally functioning brain." Even more intriguing, Gazzaniga hopes that further research will uncover an innate sense of ethics invisibly guiding human behavior.
American Scientist assistant book review editor Amos Esty asked Gazzaniga to talk more about his book and about his role on the President's Council.
You note that before serving on the President's Council on Bioethics, you hadn't given a great deal of thought to bioethical issues. Obviously that's changed. Was it primarily your experience on the council that sparked you to write this book?
It wasn't the work on the council that sparked me to write this book. The book is informed by my participation on the council, as several of the issues raised in the book were also addressed by the council. However, the idea that neuroscience has much to comment upon in dozens of areas of social concern and invention is becoming very evident. The book gave me the opportunity to lay out my thinking on a variety of such subjects.
The council has received quite a bit of criticism for what some scientists describe as conservative stances on social and scientific issues. What has your experience been? Is it difficult to find common ground when working with council members who have very different backgrounds, including many from nonscience fields?
The interesting aspect of the council is the diverse set of views that are represented. It is not a council of scientists with their practical bias toward utilitarianism. While there are some scientists on the council, there are also lawyers, moralists, philosophers, journalists, ethicists and the like. In that way, the red-button issues that come up, such as the moral status of the human embryo, unleash a lively debate. In the end it reflects more of what the real public holds near and dear versus a smaller group of scientists.
Does that ever become a problem? Are there times when scientific research gets overlooked because of people's beliefs or their instinctive reactions to an issue?
Oh, inevitably. But it works the other way around as well, and when one functions in a political world, neither myopic stance is productive.
One area you think could be greatly affected by neuroscience is the legal system. You argue that "in neuroscientific terms, no person is more or less responsible than any other for actions." This seems to imply that you would oppose the use of the insanity defense in any situation, as well as the recent Supreme Court ruling banning the death penalty for minors. Or are these examples where distinctions, however arbitrary, can still be justified?
Think of it this way: If there were only one person in the world, there would be no concept of personal responsibility. Such concepts and their importance to a culture come out and only exist in a social context. They are social rules learned by groups. Everyone can learn them, and I think everyone should be held accountable to them. The last 150 years of science is on a sure path towards determining more and more how our brains work in an automatic way. There is no getting around that fact. But that doesn't mean an automatic machine like the brain cannot learn rules. Schizophrenics stop at red lights.
You spend quite a bit of time discussing the neurological basis for our tendency to interpret the world around us, an ability that enables us to create a "unified sense of self." What is the evolutionary advantage of this tendency? Can neuroscience explain why we look for meaning?
At some point during our evolutionary history, the brain developed a capacity to ask, "How does A relate to B?" Having such a capacity clearly gives an advantage. For most things in life the question is simple enough, and the answer is simple enough. I assume the circuit in our brain that allows for this capacity was widely reinforced through natural selection. A consequence of having that capacity has got to be that one begins to ask questions about the meaning of things, of events, of our own behaviors. Out of this our personal narrative grows, and we form more questions and so on. So I would not say neuroscience can explain why we look for meaning. I would say neuroscience has identified a mechanism in the left hemisphere that appears to serve and support that function.
It seems that one of the major goals of the book is to offer neuroscience as a tool to forge a "brain-based philosophy of life." Are you, in effect, calling for a secular, scientific basis for morality?
Yes. Quite frankly, I think it must be there, and it is up to us to find how it works. There is a moral compass. We have to be smart enough to figure out how it works.
How can neuroscience help us figure that out?
The new brain-imaging methodologies that are readily available, such as functional brain imaging, TMS [transcranial magnetic stimulation], ERPs [event-related potentials], NIRS [near-infrared spectroscopy] and others, are all part of the toolbox that will help lay out the future circuits of brain function.
You predict that our growing scientific knowledge is on a "collision course" with religious belief. What might be the outcome of this collision? Is there a role for religion in a scientifically informed society?
It is crazy to think we will ever live in a world that is not dominated by people that hold religious beliefs. It is also crazy not to realize that more and more people do not hold or share those beliefs, as the result of careful, steady and rational study. The tension that naturally arises from these two forces of thought, however, need not be destructive. Religions all over the world do good, and billions of people take comfort in those beliefs. How can that be a bad thing? What has to be protected is when people who hold such beliefs want you to hold them as well. That is where a more general understanding of the human condition is important.
You comment in the introduction that you had to rethink your own approach to ethics as you worked on the book. You found that a "sense of ethics that is independent of rational science" sometimes conflicted with your scientific knowledge. In what areas was this inner conflict particularly acute? Are you more likely to trust your scientific knowledge or your instinct when the two clash?
I wish I knew.
What areas of neuroscience seem to be the most promising at the moment? Do you have any predictions about what the next big breakthrough might be?
The emergence and fusion of genomics and what might be called "neuronomics." How and what do the genes and neurons do what they do? We are closing in on it.
Check back in early June for a link to Patricia Churchland's review of The Ethical Brain, forthcoming in the July-August issue of American Scientist.