Free Will and Neuroscience

Philosophic Exchange Volume 43 Number 1 Volume 43 (2012 - 2013) 6-15-2013 Free Will and Neuroscience Alfred Mele Florida State University Follow this and additional works at: http://digitalcommons.brockport.edu/phil_ex Part of the Metaphysics Commons, Philosophy of Mind Commons, and the Philosophy of Science Commons Repository Citation Mele, Alfred (2013) "Free Will and Neuroscience," Philosophic Exchange: Vol. 43 : No. 1 , Article 3. Available at: http://digitalcommons.brockport.edu/phil_ex/vol43/iss1/3 This Article is brought to you for free and open access by Digital Commons @Brockport. It has been accepted for inclusion in Philosophic Exchange by an authorized editor of Digital Commons @Brockport. For more information, please contact . Article 3 Mele: Free Will and Neuroscience FREE WILL AND NEUROSCIENCE Alfred R. Mele Florida State University Do we have free will? If you were to Google the question, you might turn up such claims as the following: The debate about free will . . . 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. (Jerry Coyne, “Why You Don’t Really Have Free Will,” USATODAY.com, Jan. 1, 2012) “Free will” is not the defining feature of humanness, modern neuroscience implies, but is rather an illusion that endures only because biochemical complexity conceals the mechanisms of decision making. (Tom Siegfried, “The Decider,” Science News magazine, Dec. 6, 2008) Researchers have found patterns of brain activity that predict people’s decisions up to 10 seconds before they’re aware they’ve made a choice. . . . The result was hard for some to stomach because it suggested that the unconscious brain calls the shots, making free will an illusory afterthought. (Elsa Youngsteadt, “Case Closed for Free Will,” Science NOW Daily News, April 14, 2008) The concept of free will is a non-starter, both philosophically and scientifically [because] no description of mental and physical causation . . . allows for this freedom that we habitually claim for ourselves and ascribe to others. (Sam Harris, “Morality without ‘Free Will’,” Huffington Post, May 30, 2011) In Mele 2009, I argued that the scientific experiments that are most often claimed to prove that free will is an illusion actually leave the Published by Digital Commons @Brockport, 2013 1 Philosophic Exchange, Vol. 43 [2013], No. 1, Art. 3 2 existence of free will wide open. In the present article I focus on an important dimension of the issue that deserves more attention than it received in Mele 2009. Overt actions are actions that essentially involve peripheral bodily motion. Examples include signing a petition against the death penalty, proposing marriage, flexing a wrist, and pressing a button. My topic here is a scientific argument for the thesis that no overt actions are free actions (or exercises of free will) that may be sketched as follows: Skeptical Argument 1. The overt actions studied in experiments of the kind to be described do not have corresponding consciously made decisions or conscious intentions among their causes. (empirical premise) 2. So probably no overt actions have corresponding consciously made decisions or conscious intentions among their causes. (inference from 1) 3. An overt action is a free action only if it has a corresponding consciously made decision or conscious intention among its causes. (theoretical premise) 4. So probably no overt actions are free actions. (conclusion) In Mele 2009, I argued that the data I discussed there do not justify the first premise. In the present article I focus on the inference made in the second premise. In section 1, I briefly describe the experiments at issue in premise 1. The remainder of the article is a critique of premise 2. I do not discuss premise 3. 1. Some Experiments In the studies described in this section, participants are asked to report on when they had certain conscious experiences – variously described as experiences of an urge, intention, or decision to do what they did. After they act, they make their reports. In some of Benjamin Libet’s studies (1985, 2004), participants are asked to flex their right wrists whenever they wish. When participants are regularly reminded not to plan their wrist flexes and when they do not afterward say that they did some such planning, an average ramping up of EEG activity (550 ms before muscle motion begins) precedes the average reported time of the http://digitalcommons.brockport.edu/phil_ex/vol43/iss1/3 2 Mele: Free Will and Neuroscience 3 conscious experience (200 ms before muscle motion begins) by about a third of a second (1985). Libet claims that decisions about when to flex were made at the earlier of these two times (1985, p. 536). I have disputed that claim elsewhere (Mele 2009, ch. 3); but, for the sake of argument, I am supposing here that it is true. Chun Siong Soon, Marcel Brass, Hans-Jochen Heinze, and John-Dylan Haynes, commenting on Libet’s studies, write: “Because brain activity in the SMA consistently preceded the conscious decision, it has been argued that the brain had already unconsciously made a decision to move even before the subject became aware of it” (2008, p. 543). To get additional evidence about the proposition at issue, they use functional magnetic resonance imaging (fMRI) in a study of participants instructed to do the following “when they felt the urge to do so”: “decide between one of two buttons, operated by the left and right index fingers, and press it immediately” (p. 543). Soon and colleagues find that, using readings from two brain regions (one in the frontopolar cortex and the other in the parietal cortex), they are able to predict with about 60% accuracy (see Soon et al. 2008, supplementary figure 6, Haynes 2011, p. 93) which button participants will press several seconds in advance of the button press (p. 544). In another study, Soon et al. instruct participants to “decide between left and right responses at an externally determined point in time” (2008, p. 544). The subjects are to make their decision about which of two buttons to press when shown a cue and then execute their decision later, when presented with a “respond” cue (see their supplementary material on “Control fMRI experiment”). They report that one interpretation of their findings in this study is that “frontopolar cortex was the first cortical stage at which the actual decision was made, whereas precuneus was involved in storage of the decision until it reached awareness” (p. 545). In Mele n.d.a, I argue that Soon and colleagues are more likely to have detected a slight unconscious bias toward pressing a particular button on the next go than an actual decision (or intention) to press that button. But I suppose here, for the sake of argument, that, as they claim, they detect decisions several seconds in advance of button presses. Itzhak Fried, Roy Muk (...truncated)