26 March 2013

Jerry Coyne: missing the mark on free will... again

I like Jerry Coyne and I agree with him often, but whenever he starts ranting about the non-existence of free will, I have to part ways with him. He decries the compatiblism to which I subscribe, essentially arguing that all choice is illusory. 

In a post yesterday, he talked about a recent study in which, like Libet's experiments in the 1970s, researchers were able to predict subjects' decisions before the subjects were aware of making them. Coyne makes much ado of this, touting it as strong evidence that we aren't really in control of our perceived volition. But, as usual, the devil is in the details.

While I'm not going to rehash all my arguments regarding free will, I do want to summarize – I think that Jerry's position, and indeed that of all "hard determinists", is rooted in a fallacy of composition. Quarks, atoms, molecules, and neurons don't have free will; we are made of those things, ergo we do not have free will. But as is often the case in reality, a construct (like the brain) can exhibit properties not present in its constituent parts.

Then there is the question of whether choice is "real". Of course it's real. But it's here where I invoke Stephen Hawking's model-dependent realism – the idea that there is no model- or theory-independent means of understanding reality. Under model-dependent realism, it's pointless to ask what is "real", only what is the more useful description. Sean Carroll, who nicely encapsulates my position in an essay called Free Will is as Real as Baseball, has this to say:
We talk about the world using different levels of description, appropriate to the question of interest. Some levels might be thought of as “fundamental” and others as “emergent,” but they are all there. Does baseball exist? It’s nowhere to be found in the Standard Model of particle physics. But any definition of “exist” that can’t find room for baseball seems overly narrow to me. It’s true that we could take any particular example of a baseball game and choose to describe it by listing the exact quantum state of each elementary particle contained in the players and the bat and ball and the field etc. But why in the world would anyone think that is a good idea? The concept of baseball is emergent rather than fundamental, but it’s no less real for all of that.
Likewise for free will. We can be perfectly orthodox materialists and yet believe in free will, if what we mean by that is that there is a level of description that is useful in certain contexts and that includes “autonomous agents with free will” as crucial ingredients. That’s the “variety of free will worth having,” as Daniel Dennett would put it.
While Sean doesn't use the term model-dependent realism, that's the concept in a nutshell and I think it applies perfectly to our ideas of free will. Reductionism can equally be used to argue that consciousness, the self, and virtually every aspect of our human experience is illusory as well, but obviously that's not a very useful description.


So, on to Jerry Coyne's latest post. He concedes toward the end of the article that "the decisions are not readable with 100% accuracy". Uh, yeah, that's an understatement. The actual accuracy was about 60% – not much better than a coin toss. And a coin toss is exactly what it was, since the subjects were only making a simple "add or subtract" decision – hardly representative of the complex decisions we make every day. 

But even to the extent that the scientists were able to accurately predict the subjects' decisions, they did so by inferring it based upon subconscious brain activity. In other words, the process of decision making, as with virtually all cognition, may involve processes of which we are not consciously aware. So what? In no way does that undermine the reality that we are indeed making a conscious choice. Jerry, like Sam Harris, makes a big deal of the fact that much of our brains' operations are processes over which we have no conscious control. But it's a non sequitur to suggest that because we don't consciously control the processes in our brains that we have no control over our actions at all.  Sean Carroll, again:
If we know the exact quantum state of all of our atoms and forces, in principle Laplace’s Demon can predict our future. But we don’t know that, and we never will, and therefore who cares? What we are trying to do is to construct an effective understanding of human beings, not of electrons and nuclei.
I think Jerry overlooks the fact that we are our brains. Our ability to choose is therefore no more illusory than consciousness, self, or anything else encompassed by the human experience. To appeal to reductionism to undermine the reality of choice results in an absurd and ultimately useless model of human behavior.

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.