Dasein
18th August 2011, 12:07
The Illusion of Free Will, an excerpt from The Moral Landscape by Sam Harris. Dr. Harris holds a degree in philosophy from Stanford University and a Ph.D. in neuroscience from UCLA.
Brains allow organisms to alter their behavior and internal states in response to changes in the environment. The evolution of these structures, tending toward increased size and complexity, has led to vast differences in how the earth's species live.
The human brain responds to information coming from several domains: from the external world, from internal states of the body, and, increasingly, from a sphere of meaning--which includes spoken and written language, social cues, cultural norms, rituals of interaction, assumptions about the rationality of others, judgments of taste and style, etc. Generally, these domains seem unified in our experience: You spot your best friend standing on the street corner looking strangely disheveled. You recognize that she is crying and frantically dialing her cell phone. Did someone assault her? You rush to her side, feeling an acute desire to help. Your "self" seems to stand at the intersection of these lines of input and output. From this point of view, you tend to feel that you are the source of your own thoughts and actions. You decide what to do and not to do. You seem to be an agent acting of your own free will. As we will see, however, this point of view cannot be reconciled with what we know about the human brain.
We are conscious of only a tiny fraction of the information that our brains process in each moment. While we continually notice changes in our experience--in thought, mood, perception, behavior, etc.--we are utterly unaware of the neural events that produce these changes. In fact, by merely glancing at your face or listening to your tone of voice, others are often more aware of your internal states and motivations than you are. And yet most of us still feel that we are the authors of our own thoughts and actions.
All of our behavior can be traced to biological events about which we have no conscious knowledge: this has always suggested that free will is an illusion. For instance, the physiologist Benjamin Libet famously demonstrated that activity in the brain's motor regions can be detected some 350 milliseconds before a person feels that he has decided to move. Another lab recently used fMRI data to show that some "conscious" decisions can be predicated up to 10 seconds before they enter awareness (long before the preparatory motor activity detected by Libet). Clearly, findings of this kind are difficult to reconcile with the sense that one is the conscious source of one's actions. Notice that distinction between "higher" and "lower" systems in the brain gets us nowhere: for I no more initiate events in executive regions of my prefrontal cortex than I cause the creaturely outbursts of my limbic system. The truth seems inescapable: I, as the subject of my experience, cannot know what I will next think or do until a thought or intention arises; and thoughts and intentions are caused by physical events and mental stirrings of which I am not aware.
Many scientists and philosophers realized that free will could not be squared with out growing understanding of the physical world. Nevertheless, many still deny this fact. The biologist Martin Heisenberg recently observed that some fundamental processes in the brain, like the opening and closing of ion channels and the release of synaptic vesicles, occur at random, and cannot, therefore, be determined by environmental stimuli. Thus, much of our behavior can be considered "self-generated," and therein, he imagines, lies a basis for free will. But "self-generated" in this sense means only that these events originate in the brain. The same can be said for the brain states of a chicken.
If I were to learn that my decision to have a third cup of coffee this morning was due to a random release of neurotransmitters, how could the indeterminacy of the initiating event count as the free exercise of my will? Such indeterminacy, if it were generally effective throughout the brain, would obliterate any semblance of human agency. Imagine what your life would be like if all you actions, intentions, beliefs, and desires were "self-generated" in this way: you would scarcely seem to have a mind at all. You would live as one blown about by an internal wind. Actions, intentions, beliefs, and desires are the sorts of things that can exist only in a system that is significantly constrained by patterns behavior and the laws of stimulus-response. In fact, the possibility of reasoning with other human beings--or, indeed, of finding their behaviors and utterances comprehensible at all--depends on the assumption that their thoughts and actions will obediently ride the rails of a shared reality. In the limit, Heisenberg's "self-generated" mental events would amount to utter madness.
The problem is that no account of causality leaves room for free will. Thoughts, moods, and desires of every sort simply spring into view--and move us, or fail to move us, for reasons that are, from a subjective point of view, perfectly inscrutable. Why did I use the term"inscrutable" in the previous sentence? I must confess that I do not know. Was I free to do otherwise? What could such a claim possibly mean? Why, after all, didn't the word "opaque" come to mind? Well, it just didn't--and now that it vies for a place on this page, I find that I am still partial to my original choice. Am I free with respect to this preference? Am I free to feel that "opaque" is the better word, when I just do not feel that it is the better word? Am I free to change my mind? Of course not. It can only change me.
It means nothing to say that a person would have done otherwise had he chosen to do otherwise, because a person's "choices" merely appear in his mental stream as though sprung from the void. In this sense, each of us is like a phenomenological glockenspiel played by an unseen hand. From the perspective of your conscious mind, you are no more responsible for the next thing you think (and therefore do) than you are for the fact that you were born into this world.
Our belief in free will arises from our moment-to-moment ignorance of specific prior causes. The phrase "free will" describes what is feels like to be identified with the content of each thought as it arises in consciousness. Trains of thought like, "What should I get my daughter for her birthday? I know, I'll take her to a pet store and have her pick out some tropical fish," convey the apparent reality of choices, freely made. But from a deeper perspective (speaking both subjectively and objectively), thoughts simply arise (what else could they do?) unauthored and yet author to our actions.
As Daniel Dennett has pointed out, many people confuse determinism with fatalism. This give rise to questions like, "If everything is determined, why should I do anything? Why not just sit back and see what happens?" But the fact that out choices depend on prior causes does not mean that they do not matter. If I had not decided to write this book, it wouldn't have written itself. My choice to write it was unquestionably the primary cause of its coming into beings. Decisions, intentions, efforts, goals, willpower, etc., are causal states of the brain, leading to specific behaviors, and behaviors lead to outcomes in the world. Human choice, therefore, is as important as fanciers of free will believe. And to "just sit back and see what happens" is itself a choice that will produce its own consequences. It is also extremely difficult to do: just try staying in bed all day waiting for something to happen; you will find yourself assailed by the impulse to get up and do something, which will require increasingly heroic efforts to resist.
Of course, there is a distinction between voluntary and involuntary actions, but it does nothing to support the common idea of free will (nor does it depend upon it). The former are associated with felt intentions (desires, goals, expectations, etc.) while the latter are not. All of the conventional distinctions we like to make between degrees of intent--from the bizarre neurological complaint of alien hand syndrome to the premeditated actions of a sniper--can be maintained: for they simply describe what else was arising in the mind at the time an action occurred. A voluntary action is accompanied by the felt intention to carry it out, while an involuntary action isn't. Where our intentions themselves com from, however, and what determines their character in every instant, remains perfectly mysterious in subjective terms. Our sense of free will arises from a failure to appreciate this fact: we do not know what we will intend to do until the intention itself arises. To see this is to realize that you are not the author of your thoughts and actions in the way that people generally suppose. This insight does not make social and political freedom any less important, however. The freedom to do what one intends, and not to do otherwise, is no less valuable than it ever was.
Brains allow organisms to alter their behavior and internal states in response to changes in the environment. The evolution of these structures, tending toward increased size and complexity, has led to vast differences in how the earth's species live.
The human brain responds to information coming from several domains: from the external world, from internal states of the body, and, increasingly, from a sphere of meaning--which includes spoken and written language, social cues, cultural norms, rituals of interaction, assumptions about the rationality of others, judgments of taste and style, etc. Generally, these domains seem unified in our experience: You spot your best friend standing on the street corner looking strangely disheveled. You recognize that she is crying and frantically dialing her cell phone. Did someone assault her? You rush to her side, feeling an acute desire to help. Your "self" seems to stand at the intersection of these lines of input and output. From this point of view, you tend to feel that you are the source of your own thoughts and actions. You decide what to do and not to do. You seem to be an agent acting of your own free will. As we will see, however, this point of view cannot be reconciled with what we know about the human brain.
We are conscious of only a tiny fraction of the information that our brains process in each moment. While we continually notice changes in our experience--in thought, mood, perception, behavior, etc.--we are utterly unaware of the neural events that produce these changes. In fact, by merely glancing at your face or listening to your tone of voice, others are often more aware of your internal states and motivations than you are. And yet most of us still feel that we are the authors of our own thoughts and actions.
All of our behavior can be traced to biological events about which we have no conscious knowledge: this has always suggested that free will is an illusion. For instance, the physiologist Benjamin Libet famously demonstrated that activity in the brain's motor regions can be detected some 350 milliseconds before a person feels that he has decided to move. Another lab recently used fMRI data to show that some "conscious" decisions can be predicated up to 10 seconds before they enter awareness (long before the preparatory motor activity detected by Libet). Clearly, findings of this kind are difficult to reconcile with the sense that one is the conscious source of one's actions. Notice that distinction between "higher" and "lower" systems in the brain gets us nowhere: for I no more initiate events in executive regions of my prefrontal cortex than I cause the creaturely outbursts of my limbic system. The truth seems inescapable: I, as the subject of my experience, cannot know what I will next think or do until a thought or intention arises; and thoughts and intentions are caused by physical events and mental stirrings of which I am not aware.
Many scientists and philosophers realized that free will could not be squared with out growing understanding of the physical world. Nevertheless, many still deny this fact. The biologist Martin Heisenberg recently observed that some fundamental processes in the brain, like the opening and closing of ion channels and the release of synaptic vesicles, occur at random, and cannot, therefore, be determined by environmental stimuli. Thus, much of our behavior can be considered "self-generated," and therein, he imagines, lies a basis for free will. But "self-generated" in this sense means only that these events originate in the brain. The same can be said for the brain states of a chicken.
If I were to learn that my decision to have a third cup of coffee this morning was due to a random release of neurotransmitters, how could the indeterminacy of the initiating event count as the free exercise of my will? Such indeterminacy, if it were generally effective throughout the brain, would obliterate any semblance of human agency. Imagine what your life would be like if all you actions, intentions, beliefs, and desires were "self-generated" in this way: you would scarcely seem to have a mind at all. You would live as one blown about by an internal wind. Actions, intentions, beliefs, and desires are the sorts of things that can exist only in a system that is significantly constrained by patterns behavior and the laws of stimulus-response. In fact, the possibility of reasoning with other human beings--or, indeed, of finding their behaviors and utterances comprehensible at all--depends on the assumption that their thoughts and actions will obediently ride the rails of a shared reality. In the limit, Heisenberg's "self-generated" mental events would amount to utter madness.
The problem is that no account of causality leaves room for free will. Thoughts, moods, and desires of every sort simply spring into view--and move us, or fail to move us, for reasons that are, from a subjective point of view, perfectly inscrutable. Why did I use the term"inscrutable" in the previous sentence? I must confess that I do not know. Was I free to do otherwise? What could such a claim possibly mean? Why, after all, didn't the word "opaque" come to mind? Well, it just didn't--and now that it vies for a place on this page, I find that I am still partial to my original choice. Am I free with respect to this preference? Am I free to feel that "opaque" is the better word, when I just do not feel that it is the better word? Am I free to change my mind? Of course not. It can only change me.
It means nothing to say that a person would have done otherwise had he chosen to do otherwise, because a person's "choices" merely appear in his mental stream as though sprung from the void. In this sense, each of us is like a phenomenological glockenspiel played by an unseen hand. From the perspective of your conscious mind, you are no more responsible for the next thing you think (and therefore do) than you are for the fact that you were born into this world.
Our belief in free will arises from our moment-to-moment ignorance of specific prior causes. The phrase "free will" describes what is feels like to be identified with the content of each thought as it arises in consciousness. Trains of thought like, "What should I get my daughter for her birthday? I know, I'll take her to a pet store and have her pick out some tropical fish," convey the apparent reality of choices, freely made. But from a deeper perspective (speaking both subjectively and objectively), thoughts simply arise (what else could they do?) unauthored and yet author to our actions.
As Daniel Dennett has pointed out, many people confuse determinism with fatalism. This give rise to questions like, "If everything is determined, why should I do anything? Why not just sit back and see what happens?" But the fact that out choices depend on prior causes does not mean that they do not matter. If I had not decided to write this book, it wouldn't have written itself. My choice to write it was unquestionably the primary cause of its coming into beings. Decisions, intentions, efforts, goals, willpower, etc., are causal states of the brain, leading to specific behaviors, and behaviors lead to outcomes in the world. Human choice, therefore, is as important as fanciers of free will believe. And to "just sit back and see what happens" is itself a choice that will produce its own consequences. It is also extremely difficult to do: just try staying in bed all day waiting for something to happen; you will find yourself assailed by the impulse to get up and do something, which will require increasingly heroic efforts to resist.
Of course, there is a distinction between voluntary and involuntary actions, but it does nothing to support the common idea of free will (nor does it depend upon it). The former are associated with felt intentions (desires, goals, expectations, etc.) while the latter are not. All of the conventional distinctions we like to make between degrees of intent--from the bizarre neurological complaint of alien hand syndrome to the premeditated actions of a sniper--can be maintained: for they simply describe what else was arising in the mind at the time an action occurred. A voluntary action is accompanied by the felt intention to carry it out, while an involuntary action isn't. Where our intentions themselves com from, however, and what determines their character in every instant, remains perfectly mysterious in subjective terms. Our sense of free will arises from a failure to appreciate this fact: we do not know what we will intend to do until the intention itself arises. To see this is to realize that you are not the author of your thoughts and actions in the way that people generally suppose. This insight does not make social and political freedom any less important, however. The freedom to do what one intends, and not to do otherwise, is no less valuable than it ever was.