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by Massimo Pigliucci
As readers of this and of my Chicago University colleague Jerry Coyne’s blog know all too well, Jerry and I rarely see eye to eye, and seldom have any compunction in letting the world know about our disagreements. This is yet another example, which actually covers a topic that has been
debated recently at Rationally Speaking. The reason I’m taking up free will again is because Jerry recently published an op-ep
piece in USA Today confidently assuring his readers that they “don’t really have free will.” I think many of Jerry’s assertions are unfounded, and for interesting reasons.
Jerry starts out by teasing his readers about their alleged choice of reading his editorial (from which, of course, one deduces that he had no choice about writing it either), and continues: “So it is with all of our other choices: not one of them results from a free and conscious decision on our part. There is no freedom of choice, no free will. And those New Year’s resolutions you made? You had no choice about making them, and you’ll have no choice about whether you keep them.” This in philosophy is known as nihilism, a position that is commonly associated with Nietzsche and that has more recently valiantly been defended by Alex Rosenberg (I know, I keep promising to address his latest book, but it’s long, and it’s taking me some time to digest it).
Jerry’s aim is made clear by the following sentence: “The debate about free will, long the purview of philosophers alone, has been given new life by scientists, especially neuroscientists studying how the brain works. And what they’re finding supports the idea that free will is a complete illusion.” I think that Jerry is wrong on two counts here: first, neurobiology simply cannot settle the question of free will, no matter what the data; second, Jerry focuses on a very small subset of the pertinent neurobiological literature, interpreting it incorrectly.
Before we continue, however, let’s hear Jerry’s definition of free will: “I mean it [free will] simply as the way most people think of it: When faced with two or more alternatives, it’s your ability to freely and consciously choose one, either on the spot or after some deliberation.” He continues: “A practical test of free will would be this: If you were put in the same position twice — if the tape of your life could be rewound to the exact moment when you made a decision, with every circumstance leading up to that moment the same and all the molecules in the universe aligned in the same way — you could have chosen differently.”
As Jerry knows, and immediately admits in the paragraph following this quote, such a test is anything but practical. In fact, it cannot be carried out, ever. Which is why I contend that Jerry and others who push the idea that free will (and consciousness, and moral responsibility) is “an illusion” are mistaken when they think they are doing so on the basis of science. Science, if nothing else, is about empirically testable hypotheses, to which the above scenario certainly does not belong. Rather, Jerry et al. are making a metaphysical argument, an approach with which I’m fine, to a point, as a philosopher, but that is strange coming from people who clearly despise the very idea of metaphysics and scorn anything that cannot be approached by the empirical methods of science.
Knowing that his “practical test” is impossible to carry out, Jerry resorts to two lines of evidence he thinks clinch the case against free will. The first begins with the truism that we are biological organisms made of physical stuff, so that we have to abide by the laws of physics. And these laws, according to Jerry, do not leave room for free will. Of course this conclusion depends on one’s concept of free will, and there are several on offer (more on this below). It also depends on entirely unargued for assumptions, including the following: causal closure (i.e., that the currently known laws of physics encompass the totality of causal relationships in the universe); a working concept of causality (one of the most thorny philosophical concepts ever); physical determinism (which appears to be contradicted by physics itself, particularly quantum mechanics); and the non-existence of true emergent properties (i.e., of emergent behavior that actually is qualitatively novel, and doesn't simply appear to be so because of our epistemic limitations). I have opinions about all four of these points, but I don’t have a knockdown argument concerning any of them. The point is, neither does Jerry.
(Let me make clear parenthetically that I am certainly not in favor of fuzzy / mystical concepts of free will, and that I am as much of a naturalist — in the philosophical sense of the word — as Jerry. I just don’t think any of the above issues has been settled, and since it is Jerry who is making an extraordinary claim — that we are profoundly mistaken in our first person experience about free will, consciousness and morality — it seems fair to point out that he lacks the corresponding extraordinary evidence.)
Jerry’s second line of evidence for the non existence of free will draws not from physics but from neurobiology. Here he comments on recent elaborations of the famous Libet experiments about human decision making (or what cognitive scientists, and an increasing number of philosophers, refer to as volition, to get away from the theologically loaded term “free will”). Libet and others have convincingly shown that when people are asked to signal when exactly they have become aware of making the decision of pushing a button in front of a computer screen, it turns out that the decision had been made hundreds of milliseconds to several seconds before, subconsciously. That is, the brain apparently puts things in motion that will result in the pushing of a button way ahead of us becoming conscious of having made the decision to push the button.
Why this has anything at all to do with free will is a puzzle. Not even Libet himself took his experiments to show that people don’t make conscious decisions, in part because reporting awareness of an urge (in this case, of pushing a button) hardly qualifies as a conscious decision. The latter is the kind of reflective deliberation that Jerry and I engaged in while composing our respective essays, and it is simply not measured by Libet-type experiments. Indeed, it is not surprising at all that we make all sorts of unconscious decisions before we become aware of them, as any baseball batter, or anyone catching a falling object on the fly, will readily testify. Furthermore, as Alfred Mele has
argued in his book on the topic, and contrary to Jerry’s take on the neurobiological literature, there is ample empirical evidence that we do engage in conscious thinking (largely catalyzed by the prefrontal cortex), as well as, and in continuous feedback loop with, our subconscious processing of information. (Incidentally, I find it strange when some people argue that “we” are not making decisions if our subconscious is operating, since presumably we all agree that our subconscious is just as defining of “us” as conscious thinking is. Accordingly, “my brain made me do it” is hardly a defense that will fly in a court of law except, and for good reasons, in pathological cases such as behaviors resulting from brain damage.)
To recap so far: I think Jerry’s position on free will is not scientific (it is a metaphysical stance), and his two “lines of evidence” are lacking because of unargued for philosophical assumptions and because of his misreading of the neurobiological literature. But just for the sake of argument let us suspend judgment on all of this and ask Jerry the obvious question: why do we have such a pervasive “illusion” to begin with? Apparently, he knew this was coming, and answered thus in the USA Today article: “where do these illusions of both will and ‘free’ will come from? We’re not sure. I suspect that they’re the products of natural selection, perhaps because our ancestors wouldn’t thrive in small, harmonious groups — the conditions under which we evolved — if they didn’t feel responsible for their actions.”
As far as I can tell there is no empirical evidence whatsoever to support such speculation. To the contrary, we know of plenty of social animal species that seem to thrive very well indeed without requiring the illusion of free will to keep them in line. Certainly social insects don’t need to be fooled that way, and it is hard to imagine even species of social mammals, including most primates, needing to engage in deliberate reasoning before deciding how to behave toward fellow group members.
Jerry cannot resist the temptation of inserting a dig at philosophers toward the end of his essay: “philosophers have concocted ingenious rationalizations for why we nevertheless have free will of a sort. It’s all based on redefining ‘free will’ to mean something else.” There are two problems with this characterization of philosophers’ modus operandi: to begin with, it’s a case of damned if you do, damned if you don’t. If philosophers didn’t inform their reasoning with the latest science they would be criticized (justly) as being stuck in medieval scholasticism. But when they do take science on board they get accused of “rationalizing.”
In the above comment Jerry also ignores that philosophers have been debating various concepts (not definitions, because they are not ex-cathedra pronouncements) of free will for a long time. Competing approaches to free will have been put forth, among others, by Plato, Aristotle, Descartes, Hume, and more recently Daniel Dennett and Harry Frankfurt, to name but a few. It is a profound
mischaracterization of the history of philosophy to present various takes on free will as being simply reactive to the latest scientific discoveries. And of course some philosophical accounts of free will are more (and some less) in synch with scientific findings (which, it is worth bearing in mind, are themselves always tentative and sometimes spectacularly overturned). Nothing general about the nature of philosophy follows from that.
By the end of his USA Today essay Jerry finally gets to the crux of the matter: the implications of the alleged lack of free will for religion and morality. On the first count, Jerry claims that the death of free will spells the death of religion, although ironically he then mentions the Calvinist view of pre-determination. In fact, plenty of religious beliefs are compatible with lack of free will, so it seems like religion will survive even this assault (as befits an infinitely malleable tradition of made up stories).
Jerry’s second conclusion is that moral responsibility is therefore also an illusion, and that we should finally face up to this truth. Besides the obvious point that, according to his own view nobody has any choice about whether to face up to anything, what would this mean in practice? Jerry puts it this way: “we should continue to mete out punishments because those are environmental factors that can influence the brains of not only the criminal himself, but of other people as well. Seeing someone put in jail, or being put in jail yourself, can change you in a way that makes it less likely you’ll behave badly in the future.” And he goes on to say: “[we need to contemplate] the notion that things like consciousness, free choice, and even the idea of ‘me’ are but convincing illusions fashioned by natural selection ... With that under our belts, we can go about building a kinder world.”
At this point I’m truly puzzled. How is it possible to argue that we “should” do X in order to achieve Y if, as Jerry’s intellectual kin, Alex Rosenberg, would put it, “the physical facts fix all the facts”? It is hard for me to make sense of a position that denies that we have any choice in any matter, while at the same time advocating that we should or should not do certain things rather than others. How can we have a choice to contemplate (or not) what Jerry is proposing? How can we then decide to build a kinder world? And since morality itself is an illusion, why should we try to build a kinder world anyway? I’m sure I’m missing something, but I would very much like to know what that something is.
In the end, skepticism about free will seems to me to be akin to radical skepticism about reality in general (the idea that all of reality is an illusion, or a computer simulation, or something along those lines): it denies what we all think is self-evident, it cannot be defeated logically (though it is not based on empirical evidence), and it is completely irrelevant to our lives. If it teaches us anything, it is to humble us into contemplating the possibility that we may know (in the case of radical skepticism) or be able to act (in the case of free will skepticism) much less than we often smugly think — and we can all use an occasional lesson in humility. That said, we should then proceed by ignoring the radical skeptic in order to get back to the business of navigating reality, making willful decisions about our lives (including New Year’s resolutions, which actually
succeed surprisingly often), and assign moral responsibility to our and other people’s actions.