The Volitional Brain
Full Title: The Volitional Brain: Towards a Neuroscience of Free Will
Author / Editor: Benjamin Libet, Anthony Freeman and Keith Sutherland (Editors)
Publisher: Imprint Academic, 1999
Review © Metapsychology Vol. 4, No. 44
Reviewer: Jillian Scott McIntosh, Ph.D.
Posted: 11/2/2000
Are you a self? Are some of your actions willed? Do you sometimes have a choice as to what you do? Are you responsible for some of your actions? Do you sometimes do what you do because of the reasons you hold for thinking you should? What is it for a creature to be conscious? Must a creature be self-conscious in order to be conscious? What distinguishes willed from unwilled behaviour? Must a willed action be one that is freely chosen? Does this sort of freedom violate the laws of physics? Must an action for which you are responsible be one that you willed? Would a deterministic universe preclude responsibility?
This volume is an anthology of papers dealing with this wide range of questions (and more) from an equally wide range of perspectives. Neuroscience, physics, theology, philosophy, psychology, and psychiatry are all represented, as is practically every position on the above questions. This makes for an intriguing, if somewhat bumpy, ride. The book consists of eighteen articles, arranged under five headings: Neuroscience, Psychology and Psychiatry, Physics, Philosophy, and Commentary. There is also a helpful introduction by the editors, outlining some of the issues and situating the articles. The linchpin is consciousness, on the prima facie plausible grounds that volition, self-consciousness, choice, and responsibility require consciousness (though there are dissenters even within this volume). The ride is intriguing for the ground that it covers, the questions it asks, and the answers it puts forth. It’s bumpy because some articles assume answers to questions that others are attempting to answer, those answers do not form a consistent set, not all articles are concerned with the same issues, and there is substantial variety in the approaches to addressing any given topic. The inconsistency reflects a profound lack of consensus as to what the questions really are, let alone what the best answers are, and hence is part of the intrigue. Ditto, for the multitude of approaches, which also reflects the huge domain being addressed. What is less clear is how all the articles fit under the rubric “towards a neuroscience of free will”. E.g., an argument, such as Freeman’s in this anthology, to the effect that we are responsible for at least some of our non-voluntary actions, doesn’t rely on or illuminate issues in neuroscience at all.
However, given this stage of scientific and philosophical inquiry, there may be no avoiding a bumpy ride if one wants a ride at all, though this prevents succinct summarisation of said ride. Let me instead focus on some of the perspectives offered with regard to only two related considerations: 1) determinism and the free will problem, and 2) the rôle of science in answering questions about free will and responsibility. I say a few words about what else to expect in the book, and what I take its intended audience to be, toward the end of this review.
Determinism is the view that causal antecedents necessitate the effects they bring about. In the 19th c., the French mathematician Laplace speculated that a creature that knows everything about the state of the world at this instant would be able to predict the state of the world in the future, since knowing everything about this instant includes knowing the objective probabilities of future events, and these are, according to determinism, zero or one. Some have thought that this sort of determinism threatens free will. If my deciding to write this article was necessitated by prior states of myself, and in turn necessitated the writing of this article, in what sense did I choose to write it? I could hardly have done otherwise, after all. We can make the picture even more grim, by adding the claim that my writing this article was necessitated by wholly physical antecedents. The laws of physics govern the particles that make up my body (and everything else) and nothing can violate the laws of physics. Facts about my psychology add nothing to the explanation, and hence they are, at best, otiose and appealing to them certainly won’t save free will.
There are two standard non-sceptical responses to the view that determinism precludes free will: compatibilism and libertarianism (see Hodgson for dissent on this dichotomy). Compatibilism is the view that determinism and free will are not, in fact, incompatible; libertarianism is the view that they are (my causing an action is not an act of free will unless that causing was not itself determined), and that some of our actions are free. The authors that take a stand on this issue in this volume are more or less equally divided between these two camps. There is, as far as I can tell, no empirical data that could tell us which of these positions to adopt. Only libertarianism seems open to scientific investigation as a theory of how we in fact act, that is, as the view that how we act is not always determined by antecedent conditions. But having this view falsified, i.e., learning that all our actions are determined, would still leave one with choosing (“choosing”?) between accepting compatibilism and resigning oneself to there being no free will, and having it confirmed still leaves the question of how undetermined phenomena are instances of free will. Famously, Libet has argued and argues here that consciously deciding to act is ruled out as resulting in a free act on the grounds of antecedent unconscious brain activities and has hypothesised that conscious control subsequent to the intention may act as a veto, thus saving free will. Not only does this assume that something is not an act of free will if the intention to so act is not conscious at the time it is formed, but it invites the following objection, of which Libet is well aware. What evidence is there that the decision to veto is not itself made with unconscious antecedents?
A standard scientific practice in investigating how something works is to invoke “Mill’s Methods”. Synoptically, part of the idea is that if there are only two differences between how items of the same sort act, those differences are related. If my car is running and yours isn’t, and the only other difference is that yours is out of gas, we are justified in invoking the presence of gas as causally relevant. In the realm of the study of human behaviour, we can try to do the same sort of thing: person X can do P, person Y cannot, what else differentiates them? Unfortunately, attempts to do this in this context can appeal to, at best, the feeling of having done something in virtue of one’s own free will. People with obsessive-compulsive disorder (OCD) might seem to be the ideal contrast class to those with free will (see Schwartz). However, the thing that is experimentally accessible (and this on the basis of personal report) is the feeling of having chosen to do something. (See Spence and Frith for good discussion.) Certain therapies can increase the likelihood of someone saying that they feel as though they’ve chosen a particular action, but nothing follows about whether or not that action was free, and it’s not even clear that it follows that it was willed.
More fundamentally, the crucial problem for libertarians is how to make sense of free acts that are not determined. It is here that many libertarians attempt to bolster their empirical case by invoking the indeterminacy of physics at the quantum level. This meshes nicely with the objection above that free will would violate the laws of physics. How nice if free will could be vindicated by those laws. (See Hodgson, and Stapp for some discussion, Wilson, and Mohrhoff for some scepticism). Unfortunately, the best, it seems to me, that can be gained from appealing to such indeterminacy is the permissibility of reference to non-physical causes (Schwartz’s “mental force”) that are random. If they are not random, they would, eventually, violate even non-deterministic laws, but if they are random, what have we gained in terms of will, action, and responsibility? Epicurus thought that he could rescue free will by postulating random variations in the otherwise deterministic nexus (swerves in the otherwise straight trajectories of atoms, so to speak). But how would randomness ground free action?
Notice that, hard as it is, at least the study of consciousness per se isn’t usually intended to establish whether or not there is such a phenomenon. It is supposed to discover how and when humans and other creatures have it, what it’s good for (if anything), and to refine our understanding of it. (E.g., maybe there really isn’t a single unified phenomenon.) The free will problem is different.
This brings me to my second topic, the rôle of science in answering questions about free will and responsibility, to which I have already alluded. In their introduction, the editors write, “[g]iven the immense complexity of the brain, it probably is not feasible to demonstrate unequivocally the presence or absence of free will through analysis of neurophysiological processes” (p. xxi). I don’t think that it is the complexity of the brain that’s the problem here. One can grant that the complexity may preclude knowing whether or not the activity of the brain is deterministic, but this is not answering the free will question. The best (or worst) it could do is to rule out our having the sort of free will that is in conflict with determinism. In the last article, Clark accuses Libet of having an agenda, as though scientists should approach their work with an ideological clean slate. This is not possible, let alone desirable. But his point is well taken—one should take care with what conclusions one thinks the data warrants. I’m reminded of the abortion debate: it’s an empirical question, one answerable by science, as to when a foetus is viable outside the womb. But answering this question doesn’t, all by itself, tell us when it’s permissible to abort a foetus. Perhaps my scepticism is premature, but I don’t think any scientific discovery will be decisive with regard to questions of freedom and responsibility. And a lot of questionable metaphysics gets done under the guise of science. Please note—I am not saying that I think science cannot discover a lot of interesting truths about the human condition.
It is interesting that a number of the articles focus on the practical consequences of adopting one or another view. Will we be better humans or have better social systems as a result? Such considerations could play a rôle in deciding what view to adopt, but they cannot play a rôle in deciding which view is true, which I am naïve enough to think the job of science.
So, what else is in this book and what is its intended audience? A quick sampling: Spence and Frith write on the neurophysiology of the brain correlated with or constituting voluntary action, distinguishing between “intentions to act”, which are conscious to the agent, and “intentions in action”, which are not. These may fail to match in the case of “alien limb” patients, where there is an intention in action but no intention to act, and those with diseases such as Parkinson’s, in which the agent may have an intention to act, yet no action (and hence no intention in action). Schultz focuses on the activity of ganglia in primates engaged in voluntary acts. Gomes offers an excellent critique of Libet’s analysis of his own experiments, plumping for a form of compatibilism (which is implicit in many of the other pieces). He is especially good at demolishing simplistic claims along the line of the Einstein epigram of the book, an example that goes back to at least Spinoza. The idea is that if a stone (or the moon, in Einstein’s case) were suddenly to become conscious, it would think itself the source of its own motion. A lot more than that is required, as Gomes demonstrates. Bricklin and Claxton both argue that the Western common sense conception of free will is not universal and cannot withstand meditative introspection. Stapp appeals to quantum physics, but not to its indeterminacy. Rather, he investigates the phenomenon of the collapse of a wave-packet, with its essential observer, and draws conclusions about non-determined, conscious intentions. Clark offers an excellent, largely deflationary, comment at the end of the book, touching on some of the themes I touched on above.
The book is so wide-ranging, that there will likely be few competent to appreciate all the entries (this reviewer included). But there is a wealth of material to sample from. This interdisciplinarity raises a few problems (for example, Ingvar would, I think, have Kant spinning in his grave), but it is also a virtue. One gets to sample things one might not find in a more prosaic anthology. (One word of caution—it is not a self-help book.)
There is a delightful sense of being on the “frontier” in reading about such a multiplicity of investigations into volition and consciousness.
In summary, I recommend the book. It is thought-provoking (which is partly why this review is so long!).
Jillian Scott McIntosh is Assistant Professor of Philosophy at the University of Western Ontario, London, Ontario, Canada.
Categories: Philosophical, General