The No Free Will Theorem

In one sense, I'm not ready to write this post; my subconscious mental machinery is still working to sort out all of the ideas in my head. But after not having done any reading for the past few weeks, before bed I picked up where I left off reading Pierce's An Introduction to Information Theory. But I had stopped in the middle of a paragraph, decided I needed to go back to the beginning of the chapter, tried to make progress, and gave up. So I switched to where I had set aside The Best of Gene Wolfe and resumed with the story The Death of Dr. Island. A passage that I will quote later caused a cascade of, if not pieces falling into place, a clarity of what questions to think about.

Earlier this week, over at
Vox Popoli, Vox took issue with a particular scientific study that concluded on the basis of experimental data that free will does not exist. While I think I agree that this study does not show what it claims to show, I nevertheless took the approach the free will doesn't exist. The outline of a proof goes like this.

Either thought follows the laws of physics, or it does not. X or ~X. I hold the law of non-contradiction to be true. Now, someone might quibble about percentages: most of the time our thoughts follow the laws of physics, but sometimes they do not. But that misses the point.

Why would anyone suppose that our thoughts don't follow the laws of physics? Perhaps because of an idea that thought is "mystical" stuff; that there is a bit of "god stuff" in our heads that gives us the capabilities that we have. If this were so, since the Christian God transcends nature, our thoughts would transcend nature. It's how we would avoid non-existence upon physical death: the "soul" which is made of "god stuff" returns to God. Perhaps it's due to not knowing how thinking is accomplished in the brain. What I'm about to say certainly isn't taught in any Sunday school I've ever attended, or been discussed in any theological book I've ever read. While that may be because I don't get out enough, I suspect my experience isn't atypical. Another, more general reason, is because that's the way our brains perceive how they operate. It's the "default setting," as it were. Most people, regardless of upbringing, think they have free will. I think I can explain why it's that way, but that's for another post.

How does one prove that thoughts follow the laws of physics? The ultimate test would be to build a human level artificial intelligence. I can't do that. The technology isn't there. Yet. The best I can do is offer a proof of concept. I maintain that this is better than what the proponent of mystical thought can do. I know of no way to build something that doesn't obey the laws of physics. By definition, we can't do it. So any proof would have to come form some source from outside nature held to be authoritative. In my world, that's typically the Bible. There is no end of Bible scholars who hold that Scripture teaches that man has free will. It doesn't, but my intent here is to make may case, not refute their arguments. Although I acknowledge that it certainly wouldn't hurt to do so elsewhere.

What is thought? Thought is matter in motion in certain patterns. This is a key insight which must be grasped. The matter could be photons, it could be water; in our brain it is electrons. The pattern of the flow of electrons is controlled by the neurons in our brain, just like the pattern of the flow of electrons is controlled by NAND gates in a computer. While neurons and NAND gates are different in practice, they are not different in principle. NAND gates can simulate neurons (there are, after all, computer programs that do this) and neurons can simulate NAND gates (cf.
here). Another way to view this is that every time a programmer writes computer software, they are embedding thought into matter. I've been programming professionally for almost 40 years and it wasn't until recently that I understood this obvious truth. But if this is so, why aren't there intelligent computers? As I understand it, there are some 100 billion neurons in the brain with some 5 trillion connections. Computers have not yet achieved that level of complexity. Can they? How many NAND gates will it take to achieve the equivalent functionality of 5 trillion neuron connections? I don't know. But the principle is sound, even if the engineering escapes us.

Humans are governed by the laws of quantum mechanics, just as computers are. Having just re-watched all four seasons of
Battlestar Galactica on Netflix, it was fascinating to watch the denial of some humans that machines could be their equal, and the denial of some machines that they could be human. In the season 4 episode No Exit, the machine's complaint to his creator "why did you make me like this," is straight out of Romans 9. Art, great art, imitating life.

However one cares to define the concept of "free will," that definition must apply to computers as equally as it does to man. The same principles govern both. As long as it meets that criteria, I can live with silly notions of what "free" means. "You are free to wander around inside this fenced area, but you can't go outside" is usually how the definitions end up. I think limited freedom is an oxymoron, but people want to cling to their illusions.

There is so much more to cover. If our thoughts are the movement of electrons in certain patterns, then how is that motion influenced? What are the feedback loops in the brain? What is the effect of internal stimuli and external stimuli? Is one greater than the other? The Bible exhorts the Christian to place themselves where external stimuli promotes the faith. The dances of their electrons can influence the dance of our electrons. Can we make Christians (or Democrats, or Atheists, or…) through internal modification of brain structures through drugs or surgery? How does God change the path of electrons in those who believe versus those who don't? Would God save an intelligent machine? Could they be "born again"? Does God hide behind quantum indeterminacy? So many questions.

In April 2009, I wrote the post
Ecclesiastes and the Sovereignty of God, which gave excepts from the book A Time to Be Born - A Time to Die, by Robert L. Short. Using the Bible, in particular the book of Ecclesiastes, Short reaches the same conclusion I do arguing from basic physics.

The universe controls us. We do not control the universe.

This brings me to the Gene Wolfe quote mentioned at the beginning of this post:

This is what mankind has always wanted. … That the environment should respond to human thought. That is the core of magic and the oldest dream of mankind…. when humankind has dreamed of magic, the wish behind the dream has been the omnipotence of thought.

[to be continued]
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