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Free Will: Are We Truly in Control of Our Actions? Anna Slezak Dr. Hubert Bray Math 89s 27 September 2016 Slezak 2 Introduction The idea of human free will has been controversial for quite a while in the world of philosophy. In the modern world, technology exists that allows physicists and neuroscientists to quantitatively study the nature of free will as well. Even with this technology, many questions remain. Primarily, do we have free will? How do we define free will? Why does this all matter? Each discipline and each researcher offer a different approach to answering these questions, and society must evaluate each solution critically. What is free will? This simple question yields a quite complex answer and would vary depending on the source. Merriam Webster Dictionary defines free will as “the ability to make choices that are not controlled by fate or God.” A neuroscientist would explain that free will is an allusion created by the brain’s subconscious. Physics defines free will not as possibility of human choices, but in terms of the predictability of elementary particles. Sociologists do not even bother arguing over what free will is and rather focus on the implications of the concept of free will on human behavior. Obviously, there is not on straight answer to this question. In this paper, I address each viewpoint and create a complete picture of our current understanding of free will. Free will as defined by neuroscience The study of neuroscience is entirely focused on the structure and function of the nervous system, particularly the brain. This field has seen tremendous change in recent years Slezak 3 due to advances in technology. The modern theories in neuroscience would say that free will does not exist and that all human interactions are controlled by chemical and physical processes in the brain. This perspective is backed by years of research; the cornerstone of which was a controversial 1985 experiment by neuroscientist Benjamin Libet. The basis of his argument is that the human brains initiate involuntary bodily actions before the person has consciously decided to move (Clarke). Prior to Libet’s experiment, researchers discovered that there is a slow build-up of electrical potential over the motor cortex in the brain that begins as early as a second before simple motions. This measurement of this process is referred to as the Bereitschaftspotential or the readiness potential (Shibasaki & Hallett 2341-2342). Libet measured the timing of this build-up in relation to the conscious decision to move. In the actual procedure, Libet’s research team asked participants to randomly choose a time to flick their wrist. Meanwhile, they measured their brain activity in terms of the readiness potential. Libet then compared the subjects reported time of motion (in terms of position of the second hand on a clock) to the beginning of the readiness potential build up. He found that unconscious brain activity leading up to the subjects’ conscious decision to flick their wrists begins, on average, half a second before their reported decision to move. This result lead Libet to conclude that the belief of free will is an illusion and that sensation is nothing more than a retrospective view of a neurobiological process (Libet et al.). The diagram below demonstrates Libet’s findings: Slezak 4 http://rationalvedanta.com/free-will/free-will-and-consciousness-seminar-1st-february-2015/ Despite heavy criticism, these findings have been used frequently as a basis for further theories and research on the nature of free will and consciousness. More recently, Daniel Wegner, a social psychologist at Harvard University, conducted a series of experiments on the concept of free will and authored a book with his findings entitled The Illusion of Conscious Will. Wegner and his colleagues defined conscious free will as the working interaction between human thoughts and actions as having priority, consistency, and exclusivity. Priority means that the thought occurs prior to the initiation of action; consistency is described in terms of the correspondence between the thought and the action; and exclusivity meaning that the thought is the only plausible cause leading to the resulting action (Wegner & Wheatly 480-481). With this clear description of conscious free will, Wegner set out to evaluate the modern theory of conscious willingness through a series of complex neurological studies (the specific studies are to vast and complex for the purposes of this paper, but can be explored more deeply in his book The Illusion of Conscious Will). His findings revealed that our perception of free will is nothing more than an “emotion of authorship” that enables us to take mental responsibility for our actions. In other words, people claim Slezak 5 responsibility for actions that are initiated either by others or by a subconscious mental process (Clark). Wegner’s experiments and results provide strong evidence against the neurological existence of human free will and are generally accepted to be sound scientific findings (Bayne). These particular studies provide only a summary of the mass of information available on neuroscience and free will. Other notable experiments include the following: A study by Masao Matushashi and Mark Hallett which validates Libet’s findings titled “The Timing of the Conscious Intention to Move” (2008). An experiment performed by Chun Siong Soon, Marcell Brass, Hans-Jochen Heinze, and John-Dylan Haynes titled “Unconscious Determinants of Free Decisions in the Human Brain” (2008) uses fMRI scans to effectively predict subjects’ conscious choices up to seven seconds before they report making said decision. A study by Simone Kühn and Marcel Brass suggests that it is often not a conscious decision to cancel an action. Rather, it occurs as an instinct and is often mentally indistinguishable from a conscious choice. The study is titled “Retrospective Construction of the Judgement of Free Choice” (2008). Free will as defined by particle physics As the last section explains, neuroscience generally believes that humans do not possess free will. Their research tells us that people do not make conscious decisions and are not necessarily completely responsible for their actions. Particle physics and quantum mechanics begin with an entirely new approach to the study of free will, and thus an entirely new perspective. The core concepts in quantum mechanics on free will are found in the Free Will Slezak 6 Theorem, proved in 2004 by John H. Conway and Simon B. Kochen of Princeton University. The basis of the theorem is this: “If there exist experimenters with (some) free will, then elementary particles also have (some) free will” (Nagra). Simply stated, free will such that our decisions are not a function of the past can only exist if some elementary particles also have free will in this sense. In order to prove this theorem, Conway and Kochen assumed three simple physical axioms which they called fin, spin, and twin. Fin states that there exists a maximum speed at which information can be transmitted (not necessarily the speed of light). Spin deals with complex quantum mechanics and states that, “A triple experiment for the frame (x,y,z) always yields the outcomes 1, 0, 1 in some order” (“Free Will Theorem” 2). For example, when you measure the spin of a particle to be 1 in a given dimension, the measurements in other dimensions will be 1 and 0 in some order. Finally, twin states that two “entangled” elementary particles will have angular momentum of the same quantity with opposite signs. Twin is a complicated consequence of the theory of quantum entanglement and cannot be experimentally verified (Nagra). For this reason, Conway and Kochen published a continuation of the Free Will Theorem three years later called the Strong Free Will Theorem. They replaced the twin axiom with the min axiom, which is basically just a simplified version. It essentially postulates that there exists some information about the choices of measurements that does necessarily abide by the maximum speed of transmission (“Strong Free Will Theorem” 228). This new axiom accounts for complete quantum entanglement, or, as Einstein called it, “spooky action at a distance.” Slezak 7 Once a foundation had been laid in regards to the necessary assumptions of the theorem, Conway and Kochen could draw on outside sources to prove their perspective. They first draw from the Kochen-Specker theorem. For our purposes, this theorem tells us that an elementary particle does not “decide” on the value of its spin in any direction until it is measured, making clear the fact that the spin is not predetermined and therefore unable to predict from previous data (Nagra). Next, Conway and Kochen consider the Einstein-PodolskyRosen paradox. The paradox demonstrates that making a measurement on one component of a quantum system can instantaneously effect measurements elsewhere in said system (“Stronger Free Will Theorem” 228). The key component is that the effect is instantaneous and therefore not limited to a maximum speed. This means that a particle may be affected at the moment of measurement of its entangled particle, but there is no way to make a prediction on either particle prior to its measurement since the phenomenon is exactly simultaneous. So what does this all mean? The complex mathematics and quantum mechanics of the proof lead us back to a fairly simple conclusion. Essentially, if we assume experimenters are free to choose which measurements to take, the results of the measurements cannot be determined by any prior knowledge. This statement combines our knowledge of elementary particle behavior and the assumption of free will in a way that implies the existence of free will for both said particles and experimenters. Below is a visual diagram of the conclusions of the (Strong) Free Will Theorem: Slezak 8 https://www.cs.auckland.ac.nz/~jas/one/freewill-theorem.html Implications of the assumption of free will on society As seen in the previous sections, it really is not known for certain whether we as humans possess free will. The oppositional views of quantum mechanics and neurobiology make reaching any realistic conclusion very difficult. What we do understand, though, is the profound impact that the belief in free will has on human behavior. Can you imagine a world where no one took responsibility for their actions? The criminal justice system would cease to exist as lawbreakers could plead that they had no choice but to commit whatever criminal act. Religion as we know it would become obsolete, as most religions are built on the concept of human choices. The assumption of free will is integral to the proper functioning of society. To examine this issue, Roy Baumeister of Florida State University studied free will and its consequences in terms of evolutionary psychology. In his paper “Free Will in Scientific Psychology,” he proposes that “the defining thrust of human psychological evolution was selection in favor of cultural capability” (Baumeister 16). Essentially, he argues that humans are evolutionarily significant because of particular behavioral controls such as personal responsibility, autonomous initiative, and the ability to resist urges that should be instinct but run contrary to cultural norms. Baumeister also states that the two most significant aspects to free will are self-control and rational, intelligent decision making. Humans, apart from any Slezak 9 other species, have developed a complex way of controlling actions that is yet to be completely understood. Aside from the neurological or quantum mechanical perspectives, this macro-level view of human interaction yields a perspective in support of free will. Regardless of the actual mechanics at work in our minds or in elementary particles, we as humans generally believe we have free will and thus act accordingly. This human belief in free will causes Baumeister to raise an interesting question: “If free will is entirely an illusion, however, then it becomes especially perplexing that people devote so much time and effort to sustaining those illusions” (Baumeister 18). He does not ultimately answer this question, but he offers one possible solution. Past research has established that a belief in free will supports socially desirable actions. Over time, humans have evolved to hold this belief in order to better function in a social society. According to this hypothesis, it is not certain whether or not we truly have free will, but it does imply that the belief that we do is an integral aspect of our everyday interactions. Conclusion Essentially, the issue of free will remains an unsolved puzzle. The neuroscientific perspective would tell us that all of our actions are results of neurological processes and free will is nothing but an illusion. On the contrary, quantum mechanics would say that there is some degree of randomness and unpredictability in elementary particles and that the same principle can be applied to human interactions. The one thing we can agree on is the importance of free will to society. Without the assumption of free will, society would be fundamentally unable to operate like it does now. Technological advances will eventually lead Slezak 10 us to an answer, but, in the meantime, society must go on under the presumption of human free will. Slezak 11 Works Cited Andersen, Holly. "Two Causal Mistakes in Wegner’s Illusion of Conscious Will." Choice Reviews Online 40.03 (2002): n. pag. University of Pittsburg - History and Philosophy of Science. University of Pittsburg. Web. 20 Sept. 2016. Baumeister, Roy. "Free Will in Scientific Psychology." Association for Psychological Sciences 3.1 (2008): 14-19. Print. Bayne, Timothy. "Phenomenology and the Feeling of Doing: Wegner on the Conscious Will." Does Consciousness Cause Behavior? (2006): 168-85. Web. 20 Sept. 2016. Clark, Tom. "The Illusion of Conscious Will." Naturalism. Just Magic Designs, 2002. Web. 20 Sept. 2016. Clarke, Peter G.H. "The Libet Experiment and Its Implications for Conscious Will." Bethinking. UCCF: The Christian Unions, 05 Feb. 2013. Web. 19 Sept. 2016. Conway, John, and Simon Kochen. "The Free Will Theorem." ArXiv (2006): 1-30. Print. ---. "The Strong Free Will Theorem." Notices of the American Mathematical Society 56.2 (2009): 226-232. Print. Libet, Benjamin, et al. "Time of Conscious Intention to Act in Relation to Onset of Cerebral Activity (Readiness-Potential)." Brain 106.3 (1983): 623-42. Web. Nagra, Jasvir. "Conway's Proof of the Free Will Theorem." University of Auckland Department of Computer Science. Jasvir Nagra, 27 Jan. 2005. Web. 20 Sept. 2016. Shibasaki, Hiroshi, and Mark Hallett. "What Is the Bereitschaftspotential." Clinical Neurophysiology 117 (2003): 2341-356. Elsevier. 28 July 2006. Web. 19 Sept. 2016. Slezak 12 Wegner, Daniel M., and Thalia Wheatley. "Apparent Mental Causation: Sources of the Experience of Will." American Psychologist 54.7 (1999): 480-92. UCSD Cognitive Sciences. University of California, San Diego, July 1999. Web. 19 Sept. 2016.