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Is there such a thing as genuine free will?
Can we ever find out?
This philosopher says where there's a will, there's a way.
We are always acting on what has just finished happening. It happened at least 1/30th of a second ago. We think we're in the present, but we aren't. The present we know is only a movie of the past. -Tom Wolfe, The Electric Kool-Aid Acid Test (1968)
Did Tom Wolfe consciously choose to write this trippy bit of hippy wisdom 40 years ago? Or was he just on something—maybe a drug-induced wavelength from his subconscious. The questions, of course, touch on the spectacularly debated topic of free will. Does it exist? It's a question that can heat up a roomful of Bible-believers in a nanosecond.
Quite possibly, there's no other philosophical issue more storied or contentious than the issue of free will. Many thinkers, going back at least to the ancient Greek philosopher Democritus, have claimed that there is no such thing as free will—that the universe evolves according to a set of laws that determine everything that will ever happen and that humans, with their illusions of making their own choices, are just along for the ride.
Others have insisted just as vociferously that we do indeed have the power to make choices. Perhaps the most famous of these was Jean-Paul Sartre, the French existentialist philosopher, who famously argued that humans are "condemned to freedom"—they are not free to not be free.
Theologians, too, have gotten into the act, and throughout history some of the most divisive arguments in religion—Lutherans versus Calvinists, for instance, or Dvaita Hindus versus Advaita Hindus—have centered on the issue of whether humans are the ultimate arbiters of their fate or whether a higher power is pulling the strings.
Even the question of exactly what we mean by "free will" is contentious. Generally speaking, it refers to the ability to choose one's actions, but philosophers have multiple variations on that theme, each with its own implications for the human condition.
And so it might seem to make sense to let empirical science take a crack at the issue and perhaps settle it once and for all. This is, in essence, the idea behind a series of neuropsychological experiments carried out over the past couple of decades. The basic finding of this research is that people make their decisions subconsciously and only become aware of those decisions a few tenths of a second later.
But if decisions are made without conscious awareness of them, how can they be said to be the product of free will? Thus a number of the scientists carrying out this research have concluded that free will is no more than just an illusion.
Alfred Mele has three words for these scientists: "Not so fast."
In particular, Mele (pronounced "mealy"), the William H. and Lucyle T. Werkmeister Professor of Philosophy at Florida State, has recently published a book-long examination of exactly what these sorts of experiments say—and don't say—about free will. Along the way, Effective Intentions: The Power of Conscious Will (Oxford University Press, 2009) sheds some light on the often-murky interplay between science and philosophy and offers some suggestions to scientists about how they might do a better job the next time they wander into the domain of the philosopher. The book expands on some of the arguments Mele made in his earlier Free Will and Luck (Oxford University Press, 2006).
Choosing Free Will
Part of his interest in free will, Mele says, is simply the intellectual challenge of grappling with one of the deepest and most enduring of philosophical questions. But the existence or nonexistence of free will has equally interesting practical implications, he notes. In particular, over the past few years a variety of psychology experiments have shown that denying the existence of free will can lead people to behave less ethically than they otherwise would.
And perhaps even more important than the philosophical and practical issues surrounding the free will debate are the personal implications.
"It is discouraging to think we don't have any free will at all," Mele said. "Few of us are comfortable thinking of ourselves as spectators in our own lives—watching what is going on as it happens, but having no more control over the direction than a passenger on a bus."
And so it was that Mele decided he would pick up the gauntlet that had been thrown down by the neuroscientists and closely examine the experiments that were being advertised as proving free will doesn't exist. He would bring his philosopher's eye to the scientific literature and ask what was really going on.
It's a job that Mele is particularly well prepared for. From the time he was an undergraduate in college, his interests have included both philosophy and science. He entered college as a math major. During his sophomore year, after taking a course on the ancient philosophers, he decided to switch to philosophy. "I had always liked complicated puzzles and chess, and philosophy seemed to offer lots of complicated puzzles," he says.
Relatively early in his career, Mele began integrating results from psychology and other areas of science into his philosophical investigations. Intrigued by the issue of weakness of will—why people do things they recognize as wrong or, at least, as bad ideas—he began wondering what actually happens in the brain when people act in this way. This in turn led him to motivational psychology and social psychology, and he began reading and applying the scientific research.
"When I began this project in 1985," he recalls, "not many philosophers were using science, but it's much more common now." Part of the reason such work has become more widespread, he says, is because there are more scientists looking at questions with philosophical implications, such as the experiments testing awareness of one's intentions or surveys that ask people for their views on such philosophical questions as the existence of free will. Indeed, in mid-January Mele hosted a three-day international conference on "experimental philosophy" on the FSU campus.
Another scientific area that touches on issues of free will, Mele notes, is evolutionary psychology. Indeed, Roy Baumeister, FSU's Francis Eppes Professor of Psychology, has argued that free will evolved in humans as a tool for improving and maintaining social relationships, and that it is one of the evolutionary developments that make human culture possible. In this sense, Baumeister says, free will can be seen as an adaptation that allows humans to override their natural or "animal" tendencies and act instead in a way that is calculated to have more positive results in a group. It also allows humans to make the smart choice among many competing options. Of course, humans do not always make the smart choice or the "right" choice, but the fact that they developed that capacity makes good sense in evolutionary terms.
Mele came to the subject from a different angle. Over the years he had studied not only weakness of will but also a number of related topics, such as self-control, self-deception, motivation, and, eventually, the broader issue of free will. And that background, combined with his interest in using science to shed light on philosophical issues, made the neuropsychological studies of free will a subject he just couldn't pass up.
Science Kills It?
The original research, performed by Benjamin Libet of the University of California-San Francisco, in the early 1980s, was conducted to determine when the conscious intention to perform an act took place in the brain. A subject was put in a chair and hooked up to an electroencephalograph (EEG) to monitor brain activity in the cortex and to an electromyograph on the arm to detect muscle movement there. The subject was then told to flex his or her wrist whenever the feeling struck. On average, Libet found, the EEG would detect a spike of brain activity—a readiness potential—about 550 milliseconds before the myograph recorded the muscle flexing. It was what other researchers had seen—the brain seemed to decide to make a move about half a second before the movement actually occurred.
The thing that set Libet's approach apart from the research that had gone before was the introduction of what would come to be called "the Libet clock." This was an oscilloscope set up to create a dot circling the face of the oscilloscope about every two-and-a-half seconds. The subjects were instructed to watch the clock and, after the wrist flexing, to note on a clock face where the dot on the oscilloscope had been when they had become aware of the intention to flex the wrist.
What Libet discovered—and what eventually would lead to the claims that science had killed free will—was that the subjects reported first being aware of the intention to move their wrists about 200 milliseconds before the movement actually occurred, or about a third of a second after the brain had seemingly decided to move the wrist.
Since Libet's original study, the experiment has been repeated in various forms hundreds of times, both by Libet (who died in 2007) and many other researchers. The variations on the basic design include such things as having the subject click a mouse instead of flexing a wrist, or having the subject decide immediately before the movement whether to use the right or the left hand, but the basic pattern that Libet found always emerges. First, there is a spike of activity in the cortex; then, a few tenths of a second later, the subject reports being aware of the intention to move; then, a couple of tenths of a second after that, the subject moves.
The work made Libet the widely acknowledged leader of the field of conscious volitional acts, and thus his interpretation of the experiments has been widely accepted. What Libet and his students have claimed is that these experiments show there can be no free will, at least in terms of choosing to initiate an action, since the conscious mind is not even aware of the initiation until after it happens.
The sense that one has consciously decided to make a movement is simply an illusion created by a conscious mind eager to believe that it is in control, the findings suggested. The strongest form of this claim, embraced by many neuropsychologists, is that all decisions to act are made subconsciously and, when the conscious brain becomes aware of them, it fools itself into thinking that it actually made the decision. The conscious mind believes itself to be in control, but it is not.
But Mele argues that there are a number of reasons to believe the story is not so simple, and he spends much of his book laying them out in detail. His argument begins with a careful examination of how the Libet-type experiments are carried out.
"The whole thing takes about two hours," he said. Mele knows firsthand because once, while visiting the National Institutes of Health, he got the chance to be the subject himself in one of these tests.
His first surprise was that after having been wired up and instructed on what to do, he felt no spontaneous urge to flex his wrist. So having sat there for a while with no flexes, he decided he would say "Now" silently to himself and use that as a signal to flex. That worked, but now the experimenter told him his flexes were too "wimpy." He needed to flex more. So he did, and the signal from the myograph came through clearly.
But now he discovered a bigger problem—figuring out where the spot on the Libet clock was when he became aware of his intention.
"I could narrow it down to maybe 20 percent of the clock, and I just chose the midpoint of that. But I was really just guessing where the spot was."
And this is one of the weaknesses of the experiment that Mele discusses in his book: the uncertainty inherent in pinpointing the moment of awareness of the intention to move. When Mele examined the raw data from some of these experiments, he found that the timing was actually all over the map. Some subjects indicated awareness of the intention as much as a full second before the muscle activity, while others indicated that the awareness took place after the muscle movement. "These are all averages with a wide distribution," he said.
Furthermore, the time indicated as the moment of awareness of the intention can be influenced by a number of factors. One experiment found that simply accompanying a subject's mouse click with an audible beep but having the beep come a few tens of milliseconds after the mouse click was enough to cause the subjects to modify when they reported awareness of the intention to move—even though the beep came well after the awareness.
"This implies that the subjects are estimating the time," Mele says. "You don't take a snapshot in your head and remember the clock position. You estimate it, and your estimate is influenced by other factors."
In short, one cannot be too confident of the subjects' reports on just when they became aware of their intention to move their wrists.
But Mele's most serious challenge to the interpretation of these experiments is centered on the issue of what the spike in brain activity half a second before the movement really means. Those who see the experiments as having disproved the existence of free will assume that the brain activity marks some sort of decision by the brain and that, once the neuronal firing is complete, the hand movement is inevitable. Yet there are many reasons to believe that is not the case, Mele says.
First, the timing is wrong, he said. Other experiments where people respond to a sound by clicking a mouse indicate an average reaction time of about 230 milliseconds. So if the brain activity observed in the Libet experiments really is an irrevocable decision to move one's hand, why does it take 550 milliseconds to complete the movement?
Second, a number of the subjects in Libet-type experiments have reported the experience of having the urge to move a hand but resisting that urge. This implies, Mele says, that there is no inevitability connected with that brain activity. The unconscious brain is making a suggestion, but the conscious brain still has the ability to say yes or no.
"Think about grabbing a plate of food from the microwave," he says. "It's very hot, and you have a sudden urge to drop it, but you know that will make a mess, so you hold onto it for long enough to place it down on the counter." The brain activity seen in the Libet test corresponds to your brain sending the signal, "Drop the plate!" but the conscious decision whether to obey that urge is a different process and one that has not—yet—been observed by the EEGs of the experimenters.
Libet himself recognized the ability of people to veto these urges but did not see this as an indication of free will. He called the ability instead "free won't" and argued that since the instigation of an action is done unconsciously, people do not truly decide what they are going to do, only what they are not going to do.
Mele sees it differently. If the same brain activity—the readiness potential—can precede either an action or a lack of action depending on whether one chooses to go through with it, then that brain activity cannot be thought of as marking a point of decision. One can consider the brain activity to make an "urge" to do something, perhaps, but not a decision.
Certainly the brain subconsciously generates a variety of urges that the conscious mind—if it's paying attention—can choose to follow through on or not. Your nose itches, and you reach up to scratch it. That may happen completely without you being aware of what you're doing, or, if you have some reason not to do it—you're giving a talk in front of an important audience, say—then you may squash the urge before it can be carried out.
But neither of those situations is the same as if you say to yourself, "I think I'll reach up and scratch my nose just to prove I can without some unconscious urge pushing me to." And then you do it. That is more like what most people imagine when they think of free will.
It's Alive, For Now
But more to the point, Mele argues, none of these minor choices really gets to the heart of free will. "How much does a muscle movement decision really have to do with normal life decisions, such as where to eat or whether to propose marriage?" he asks.
The Libet-type experiments do not ask people to put much thought into their decisions. Instead, the subjects are told what to do, and the only choices left are such things as when exactly to do it and perhaps which hand to do it with. If indeed the subconscious part of the brain is making suggestions about timing or which hand to use—suggestions that the conscious part of the brain can choose to accept or not—then that is an interesting bit of information concerning how actions are initiated, but it says absolutely nothing about larger decisions such as whether to take part in a Libet-type experiment in the first place.
Mele's arguments are heard and respected by many of the scientists whose research touches on free will, Baumeister says. "Al's work has been a profound and thoughtful corrective for many of the mistakes leading scientists are making," he says. "He has shown that a lot of the debate is based on a false dichotomy—the assumption that behavior is produced either by conscious or by unconscious processes."
Looking to the future, Mele suggests that it would be useful for researchers to perform experiments that measure choices or decisions themselves rather than the things, such as the readiness potential, that lead up to the decisions. And clearer terminology is needed. People, particularly those in different fields, often use such words as "intention" or "decision" in different ways.
But for now, at least, free will is still alive and well, Mele says. "No existing experiment has shown that we don't have free will." And, with luck, he says, none ever will.