Friday, November 18, 2005

On Free Will: Part I

Introduction

I've been meaning to post something on free will, given a recent conversation I had (you know who you are), but the topic is so rich, I imagine it will grow into several posts.

I can kick it off with a recent anecdote. I was having a conversation with a very prominent government official. I can't identify him by name or by title to protect his identity (and to some extent to protect my own anonymity), but suffice it to say that he operates at the highest level of government and is on first name basis with at least one Supreme Court justice and the current resident of the Naval Observatory. I say this not to impress but to give you some context.

We were discussing Consilience, a book by E.O. Wilson, a Harvard biologist, which he had read and I have not. Wilson's basic thesis is that the human condition, its literature, its religion, and its culture will one day be understood through the study of physical processes, particularly the brain. The official told me that he envisions that one day, but not in his lifetime, and in all likelihood not mine either, neuroscience will be able to achieve complete understanding of how the brain shaped the human condition.

Now this happens to be a small pet cause of mine, especially after reading the seminal book How the Mind Works by Steven Pinker and On Intelligence by Jeff Hawkins. So I asked him the next logical question: How did he think society would react when neuroscience is able to demonstrate the non-existence of free will. (This is not beyond possibility, the technical minded can imagine an experiment which would demonstrate the mind as a Turing machine or an Oracle.)

His response:
"What do I care, I'll be dead?"

Tolstoy vs. Carmell

I finished reading Tolstoy's War and Peace over Simchas Torah, but lingered over his second epilogue, which is basically a treatment of free will and history. In it he utterly destroys a kiruv clowny argument made by Aryeh Carmell in his essay "Freedom, Providence, and the Scientific Outlook," which I read in Challenge, a collection of essays on reconciling Torah and science edited by Carmell. I don't want to knock the essay too badly, because some of it is quite good, especially the section that addresses the semantics of free will. And, although for some odd reason he bothers to discuss it, he eliminates quantum mechanics and the uncertainty principle as possible saviors of free will. He also has some strange speculation of the existence of a mindon or psychon fundamental particle responsible for free will, which quite frankly is entirely kiruv clowny.

In his essay, Carmell writes:
In any case, if there were indeed a conflict between physics and free will, which would have the burden of proof? Which represents itself with more certainty to the human mind? The laws of physics are, after all, derivative, while of my ability to make decisions I have direct cognisance.

Arthur H. Compton, the Nobel physicist, put this point very forcefully: "One's ability to move his hand at will is much more directly and certainly known than are even the well-tested laws of Newton and...if these laws deny one's ability to move his hand at will, the preferable conclusion is that Newton's laws require modification."

Compton did not of course mean his remarks to apply only to Newtonian physics. They apply certainly with no less force to modern physics with its basically statistical laws.
Phew. So basically free will exists because we think it does. It is odd for a scientist to trust his own intuition over physical law, no?

As it turns out Tolstoy thought so too. In his second epilogue to War and Peace he writes:
(1) To whatever degree we may imagine a man to be exempt from the influence of the external world, we never get a conception of freedom in space. Every human action is inevitably conditioned by what surrounds him and by his own body. I lift my arm and let it fall. My action seems to me free; but asking myself whether I could raise my arm in every direction, I see that I raised it in the direction in which there was least obstruction to that action either from things around me or from the construction of my own body. I chose one out of all the possible directions because in it there were fewest obstacles. For my action to be free it was necessary that it should encounter no obstacles. To conceive of a man being free we must imagine him outside space, which is evidently impossible.

(2) However much we approximate the time of judgment to the time of the deed, we never get a conception of freedom in time. For if I examine an action committed a second ago I must still recognize it as not being free, for it is irrevocably linked to the moment at which it was committed. Can I lift my arm? I lift it, but ask myself: could I have abstained from lifting my arm at the moment that has already passed? To convince myself of this I do not lift it the next moment. But I am not now abstaining from doing so at the first moment when I asked the question. Time has gone by which I could not detain, the arm I then lifted is no longer the same as the arm I now refrain from lifting, nor is the air in which I lifted it the same that now surrounds me. The moment in which the first movement was made is irrevocable, and at that moment I could make only one movement, and whatever movement I made would be the only one. That I did not lift my arm a moment later does not prove that I could have abstained from lifting it then. And since I could make only one movement at that single moment of time, it could not have been any other. To imagine it as free, it is necessary to imagine it in the present, on the boundary between the past and the future- that is, outside time, which is impossible.

(3) However much the difficulty of understanding the causes may be increased, we never reach a conception of complete freedom, that is, an absence of cause. However inaccessible to us may be the cause of the expression of will in any action, our own or another's, the first demand of reason is the assumption of and search for a cause, for without a cause no phenomenon is conceivable. I raise my arm to perform an action independently of any cause, but my wish to perform an action without a cause is the cause of my action.

The arm raising thought experiment is nonsensical and it taints Carmell's essay. What is interesting is that neither Tolstoy nor Carmell inform their work with any neuroscience. Tolstoy, writing in the 19th century, had an excuse.