Thursday, September 16, 2010

The "Free" in Free Will

A few nights ago, I was having a chat with some of my atheist/agnostic friends about free will. While we seem to agree on the way things actually are, there was some disagreement as to whether we have free will. After some discussion, I think I discovered that for most of my friends, free means "not deterministic" or "not deterministic and not random". And, since my friends think the universe is pretty much deterministic, they don't believe free will exists.

If this was just a dispute about terminology, there wouldn't be much more to say. However, I could tell that for one or two of my colleagues, this lack of free will was the source of some angst. Why should that be? Why should anyone care about a rather mathematical abstraction like determinism?

This got me thinking more about value. Daniel Dennett says that determinism gives us all the free will that's worth having. So, what is it that we value?

In my opinion, what people value is the product of the work they do when making decisions. They want to have made good decisions for good reasons. What I intend to argue here is that throwing non-deterministic factors into decision-making will not increase what we value about our decision-making.

The short version of the argument is simply this: a good reasoner is determined to get to a good conclusion from initial premises.

Consider the classic Socrates syllogism:

Premise 1: All men are mortal.
Premise 2: Socrates is a man.


Conclusion: Socrates is mortal.

If we assume the premises, then the conclusion follows. Any person who assumes the premises, but determines that Socrates is not mortal is a bad reasoner. Injecting non-deterministic factors into the reasoning process will only make a good reasoner worse!

What's more, this syllogism is constant and time-independent. It's as true today as it was a billion years ago, or as it will be billion years in the future. The validity of the syllogism is a timeless fact. The thing that is time-dependent, the thing that happens in time, is the way our mind parses and traverses this timeless logical fact. And here, non-determinism in the conclusion one reaches will only make a good reasoner worse.

To be a bit more precise, getting to a non-deterministic conclusion would only make things better if we were really bad at reasoning. If our reasoning ability was worse than random guessing (e.g., if we pathologically got to wrong conclusions), then a non-deterministic element might improve our score, but I don't think we would value random guessing a whole lot more than we would value being absolutely awful at reasoning. Guessing just isn't the kind of reasoning we value.

The other reason why we might devalue deterministic reasoning is that the kind of deterministic reasoning that's on the table is physical determinism. If reasoning is the result of chemical interactions, then people worry that they didn't act for good reasons, but just because some electrons and nuclei buzzed around in their heads and created a new configuration. They worry that physical reasons are mutually exclusive of conceptual reasons.

This worry is the source of an anti-naturalistic argument called the Argument from Reason. The basic idea is that, if matter is not fundamentally mental at its lowest level, then thoughts are the results of non-mental physics (like chemistry). And if thoughts are non-mental underneath, then thoughts aren't really about things, and decisions are not for the reasons we think they are. And if reasons aren't reasons, then the reasons we gave for concluding that the world is based on non-mental physics are worthless, and naturalism is self-refuting.

I think the Argument from Reason is simultaneously under-appreciated and wrong. It's difficult to fault most naturalists when they follow scientific inferences and conclude that the mind is a biochemical mechanism, but I also think that it's important for naturalists to understand why the Argument from Reason is wrong.

The Argument from Reason assumes that things that occur for physical or chemical reasons cannot also occur for reasons in the world of ideas. This assumption seems reasonable at first. If we know that X is necessary and sufficient cause for Y, then we generally discount other, independent causes. In this case, if physics is a necessary and sufficient cause for what we think and do, then reasons from the world of ideas should be discounted as reasons for our thinking.

Greedy Reductionism
The problem with the assumption underneath the Argument from Reason is that it relies on something called greedy reductionism. Greedy reductionism is another expression we owe to Daniel Dennett. Reductionism is something that comes from the physical sciences. Historically, we have found that wide variety of objects and phenomena are actually the result of just a few kinds of objects and a few kinds of phenomena. For example, the periodic table of elements contains over a hundred chemical elements, and the number of chemical interaction phenomena is vast. However, we have discovered that chemistry is just the result of protons, neutrons and electrons interacting electromagnetically. The vast science of chemistry reduces to the physics of a few kinds of things that interact in one simple way. The complexity arises from the vast number of configurations that can arise from some simple physics. Carbon has unique chemical properties, but carbon is actually the result of electromagnetism plus protons, neutrons and electrons.

The greedy reductionist is the philosopher who takes this information and claims that chemical elements don't exist anymore. This is not an idea from the sciences. It is a confusion.

Reductionism identifies the thing being reduced with a configuration of something more fundamental. Reductionism doesn't replace the thing being reduced, but merely explains it. Our description of an interaction might be replaced by reductionism (e.g., a chemical reaction might better be described as an electromagnetic interaction between electrons), but the original thing is never eliminated by reductionism.

Minds have thoughts, and make decisions for reasons. If minds, thoughts and reasons reduce to physical mechanisms, then we eliminate neither minds, thoughts nor reasons. Those who champion physicalism are not saying that minds, thoughts and reasons do not exist. They are saying that minds, thoughts and reasons are physics. They are physical processes, states or configurations. Physics is not an alternative to thoughts and reasons as an explanation for thinking, but one and the same. Thinking is a physical process in humans.

This means that the physics of minds is not an explanation for thoughts that is independent of the conceptual reasons. And since physical mechanisms are not independent explanations, physical mechanisms are not mutually exclusive of conceptual mechanisms.

Explaining precisely how I thinking is a physical process is beyond the scope of this post, and, besides, I don't think such and explanation is necessary to refute the Argument from Reason. The Argument from Reason is really a gaps argument which says "I don't see how thinking can be a physical process, therefore it cannot be a physical process."

In summary, while the meaning of the word free is a matter of convention, I think that defining the word free to mean non-deterministic is confusing and counterproductive. What we care about is whether we have the kind of will that is valuable, and non-determinism doesn't help us get what we value.

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