We humans love our dualisms: good or evil, hot or cold, free or determined. Who's in Charge?, a book extrapolated from the author's 2009/10 Gifford Lectures, is a book that questions that last dualism. Given what we know about the brain, Gazzaniga writes, it is not quite clear whether the idea of 'free will' really makes sense (as generally conceived) or if determinism really has the implications we usually think it does.
Here is the picture Gazzaniga (roughly) paints. Marshaling much evidence from his and others' studies, it appears that our brain is something like a collection of modules performing different functions WITHOUT that 'central command' module that is supposed to approximate the free will (like a president who has final signing or veto power over bills). Moreover, that feeling we have of a unified conscious experience is most likely the result not of a 'central commander' module, but a module (appropriately) referred to as 'the interpreter,' whose role is to construct (somewhat) post hoc explanations of why we did what we did AS IF we were really conscious in doing it. Here, Gazzaniga draws on research of split-brain patients, whose corpus collossums are severed, disallowing their left and right brain hemispheres from talking to each other. Studies show that when the right hemisphere is told to do something (say, the left eye is shown a word and the patient is asked to grab the object that they are shown from an array of objects), the left hemisphere (where the interpreter is) will often construct a rationale for why the patient grabbed the object (that has nothing to do with the instructions to the right hemisphere). For a simpler example of the interpreter in action, think about when you hit your thumb with a hammer. Our pulling away of our thumb is usually automatic, before any pain is consciously felt, but when asked, people often say (and think) they pulled their thumb away because of the pain.
If this seems like depressing robotic determinism where "we" are not in charge of "our" brains, the next chapters might offer some relief. Gazzaniga questions the reductionism behind attempts to reduce the mind to the brain. Yes, he says, the mind is an outgrowth of the brain, its neurons, and its synapses. But as far as we can tell, the mind is an emergent property that is simply more than the sum of its parts. In the same way that while social groups are actually collections of individuals, but social behavior cannot be predicted solely by appealing to individual behavior (and social behavior can actually constrain individual behavior as easy as vice versa), Gazzaniga argues that the mind may just constrain the brain that gave rise to it. Add to that some developments like chaos theory, the butterfly effect, etc, that uproot some of our long-held notions about the determinism of the universe, and we at least have reason to doubt that our notions of causality and determinism when it comes to humans (if not elsewhere) are assumptive at best.
The final chapters deal with the idea of responsibility. As Gazzaniga points out, responsibility is a concept that only has any meaning in a social context. Asking whether I am responsible for my behavior is essentially a question about moral praiseworthiness and blameworthiness, and whether deserts are just in particular cases. The reason we have these concepts is inherently social, and so is the morality and law that we base these ideas on. Whether or not someone was consciously in control of their action is, to Gazzaniga, an interesting but irrelevant point to the working of justice. The question is - and the rationale for law is - whether certain actions should be punished in order to preserve civil society. (And by Gazzaniga and others' theories, it makes little sense to even ask whether I was or was not in control of an act that I performed, because if I performed it, something in me was responsible for it. Whether the interpreter can spin a story about it is irrelevant.)
It may be needless to say, but this book is both intriguing and unsettling. Gazzaniga is no philosopher and many of the deeper questions his ideas evoke have to wait until the philosophers get ahold of it. While Gazzaniga is very convinced that the brain's function (among other things) is as a decision machine, it is difficult to see how that works in absence of a 'central commander' doing the presidential deciding. Another question that Gazzaniga doesn't address is how our vocabulary should change when discussing ideas about free will versus determinism. He is certain that our vocabulary must change in order to be accurate (he rhetorically asks what it is that free-willers want to be free from), but doesn't give much clue as to how we might go about this. Does it even make sense to ask whether "I" am in charge of "my" actions, as if there is an "I" that is distinct from all the subconscious parts of me (like, can I really ask whether I am in charge of my breathing? In one way, it is obvious that I am not, and in another way, it is clear that I am.). There are many other questions this book evokes, but I am sure each reader will find their own. Either way, it is remarkable fun to read, absorb, and puzzle over the vast territory Michael Gazzaniga exposes us to here.
Who's in Charge? is not in any sense an easy read. While Gazzaniga makes it easier than it probably could be in the hands of a less skilled writer, the middle chapters in particular (where we are getting familiar with the idea of the mind as an emergent property of the brain and the physics that helps explain it) are slow going. But Gazzaniga does a good job in using analogies, anecdotes, and plain language to make his points, and the careful and patient reader will be rewarded with a very interesting theory about how humans really work. While Gazzaniga does not leave all ends tied up (there are some loose ends left), he has written a very powerful survey of what neuroscience is telling us about who is in charge.