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1 March 2012 Who's in Charge: Free Will and the Science of the Brain
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Michael S. Gazzaniga, who serves on the President's Council on Bioethics, is director of the SAGE Center for the Study of the Mind at the University of California, Santa Barbara, and Director of the Summer Institute in Cognitive Neuroscience at Dartmouth. Readers who expect to learn from his book Who's in Charge: Free Will and the Science of the Brain about brains and phenomena like consciousness, delusions, and confabulation will not be disappointed. They may be surprised, however, to find that they are also learning about quantum mechanics, chaos theory, law, punishment, and evolution. Based on the author's 2009 Gifford Lectures titled “The science of mind constraining matter,” this volume is impressive in its wide range of material, yet its thesis is simple: We are personally responsible and accountable agents, and scientific findings do not undermine this contention.


This is a highly readable, entertaining, and informative book. In a chapter on law, Gazzaniga makes it clear that the kind of responsibility he has in mind is directly relevant to legal judgments of guilt. But what about free will? The term appears in the book's subtitle, after all. His answer involves a ghostly or nonphysical element and “some secret stuff that is YOU” (p. 108). Here, of course, he is not reporting on a scientific discovery about free will; he is conveying how he understands the expression.

Given what the term means to Gazzaniga, it is no surprise that, in his view, “free will is a miscast concept, based on social and psychological beliefs… that have not been borne out and/ or are at odds with modern scientific knowledge about the nature of our universe” (p. 219). If he were to believe that personal responsibility depends on free will, he would, of course, take a similarly dim view of responsibility. But Gazzaniga sees personal responsibility very differently: Free will is magical; responsibility is not. “The issue isn't whether or not we are ‘free.’ The issue is that there is no scientific reason not to hold people accountable and responsible” (p. 106).

Why might some people think that scientific findings undermine Gazzaniga's contention that we are accountable for some of our actions? Some might believe both that personal responsibility depends on our having conscious control, and recent experiments have shown that, in fact, unconscious brain processes call all the shots. In the book, Gazzaniga positions himself to take on this challenge: He reviews some of what is known about how human brains work and how they evolved, and he makes an engaging effort to explain how the brain fits into the rest of the universe.

We learn about differences between human and nonhuman brains, split-brain studies, the left-brain interpreter, and what gives individuals a feeling of psychological unity and control. Gazzaniga contends that while the brain enables and generates the mind, “the mind constrains the brain” and “responsibility arises out of social interaction” (p. 144). We become acquainted with the idea of personal responsibility through social interaction, and in the process we gain an ability that is important to our survival—our ability to know what other people intend and how they feel about things. Intentions and feelings are mental phenomena, and our mental grasp of these phenomena affects unconscious brain processes.

This is not to say that we have nonphysical minds (or souls). Rather, one thing human brains do is enable and generate very useful conscious experiences. The ability to have such experiences emerges out of the interactions among brains (p. 133). And this ability facilitates social interaction, learning, and survival.

This is all very reassuring, but at times in the book, Gazzaniga sells our mental life short. For example, he writes, “When we set out to explain our actions, they are all post hoc explanations, using post hoc observations with no access to nonconscious processing” (p. 77). Is it true that we never succeed in explaining our actions at least partly in terms of conscious processing that preceded them? Consider selecting an exit row seat for extra leg room when booking a long airplane flight. I have a conscious preference for extra leg room, especially on long flights. If I were to explain why I chose a particular seat—or why I might be sitting in a particular seat on a flight—I could offer an answer in terms of that conscious preference, and this explanation would not invoke a nonphysical mind any more than Gazzaniga's position on emergent mental properties invokes one.

Gazzaniga may be overly impressed by some of the experiments he discusses—well-known investigations by Benjamin Libet and the more recent work by Chun Siong Soon and colleagues. On the basis of brain activity as measured by blood flow, Soon and colleagues were able to predict with 60-percent accuracy about seven seconds in advance of the action itself whether a person would press a left button or a right button. Each person was supposed to decide on a button and then immediately press it. What does this early brain activity signify? Perhaps it signifies just an unconscious bias toward a particular button. In any case, there is no reason to prefer either button over the other, and because there is no place in the experiment for conscious reflection, there is no place for an explanation of the action in terms of conscious reasoning. The same general point applies to Libet's studies, whose subjects arbitrarily choose a moment to begin flexing their wrists. I discussed experiments of this kind at length in my book Effective Intentions (2009).

When it comes to my selecting an exit row seat, things are very different. I know I have a reason—a good one—to select such a seat rather than an ordinary seat in coach. Because I do, I consciously look online for an open seat in an exit row. (I don't know how to do this unconsciously.) By the way, given what I have told you, you can predict with close to 100 percent accuracy what I will try to do next time I buy a coach seat on a long flight, and you have achieved this degree of accuracy for free, just by consciously attending to what I wrote.

I feel compelled to make one last point. Many people think that what they call “free will” is required for personal (and legal) responsibility. If Gazzaniga's own conception of free will as a magical power is out of line with mainstream conceptions of it, then, in defending the existence of personal responsibility, he may also unwittingly be defending the existence of free will.

and Alfred R. Mele "Who's in Charge: Free Will and the Science of the Brain," BioScience 62(3), (1 March 2012).

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