Thoughts on Free Will
I love watching Christopher Hitchens. Although we don’t agree on everything, he’s probably my favorite debater. He has the important skills: passion, eloquence, command of facts. And, he favors the Oxford debate style, where the goal is to be right, rather than to build consensus.
But I always cringe when he gets asked about free will. Hitchens is, I think, at core an anti-totalitarian of the Orwell cast. So, despite being an avowed Atheist, he bristles at the idea of agreeing that there is no free will, even though it is the consequence of believing in a deterministic materialistic reality. He inevitably gives the same answer – “I have no choice.” It’s clever, but it’s clearly a dodge.
It got me thinking on the question, and I think I’ve reached some interesting conclusions. This essay will probably be a bit involved, so please get a cup of tea or coffee before you jump down the rabbit hole with me.
As I see it, there are both necessary and sufficient conditions for free will. These can be made more specific, but the general idea is this:
The necessary condition for free will is that the universe (or multiverse) be non-deterministic.
The sufficient condition for free will is that human beings have some sort of access to the necessary condition.
That leaves 5 possibilities:
1) Universe is deterministic, so we have no free will. (Determinism)
2) Universe is deterministic, but we still have free will. (I would call this a religious argument)
3) Universe is non-deterministic, and we have free will. (Hooray!)
4) Universe is non-deterministic, but we have no free will. (That is, for example, humans are predictable but electrons aren’t).
5) There’s some other possibility I’m not considering.
Let’s look at the necessary condition first. For a long time, I was troubled by this thought experiment: Let us suppose that the universe is deterministic, meaning that each action is simply the result of the prior moment. Now, let us suppose that in this universe, you took a subsection (say a 20x20x20 meter cube) and built a computer that knew all the parameters of everything inside. Let’s also suppose there’s a person inside. Now, suppose the computer predicts to the human, that today for lunch he’ll have a ham sandwich. What’s to stop the human at that point from defying the prediction?
This confused me because it seems like you arrive at a contradiction by assuming a deterministic reality. But, I thought about it more, and I eventually arrived at this conclusion: The thought experiment is faulty, because the monitoring computer has to be considered part of the system. That is, in order to know it’s predicting correctly, the computer must know the state of all of its own parameters in addition to the parameters in the cube. This seems to me to be impossible, because the computer would have to perfectly simulate a system more complex than itself! This leads to even deeper problems, since (if true) it’d mean that even if reality is deterministic it could never be determined, even by a being who exists outside of reality.
After that, I started to wonder if philosophy wasn’t the right way to approach this problem, at least not yet. After all, free will is essentially an empirical question, at least as posed above. Does the universe meet the necessary condition, and do humans meet the sufficient condition?
For the necessary condition, it’s useful to look to physics. Although determinism makes intuitive sense (since it seems impossible to have effects without causes and vice versa), there are strange things in physics that make you wonder if reality is actually non-deterministic. So, it seems to me that we don’t have an answer for the necessary condition, as it is an empirical query without an answer.
But let’s not stop there. This opens up another possibility. What if there is no answer to the necessary condition? That is, suppose we discover that for good scientific reasons it is never possible to determine whether reality is deterministic or not. Does that mean reality may as well be non-deterministic? After all, if we can never know the answer, pragmatically speaking any answer is appropriate.
I think that, if the necessary condition is impossible to get it, it may be worthwhile to consider the sufficient condition. For, if the sufficient condition cannot be met, the necessary condition is moot.
I think it’s conceivable that you could have a non-deterministic world that has deterministic stuff in it. For example, it’s possible to imagine a complex molecule whose components have some quantum wobble to them, but which in aggregate interact at a purely chemical level.
If that’s the case, we have to ask ourselves whether there’s an evolutionary advantage to free will that’d cause access to it to be a fitness advantage. An simple example of animal access to free will would be a machine in the brain that performs the double slit experiment every time your brain needs a random number for something. Okay, bit of a lame example, but I think it’s a decent proof of concept. You can imagine how a creature that is capable of truly random action might strategically outdo an opponent who behaves in very recognizable patterns. Anyone who’s ever played a single player video game long enough to exploit the AI knows this to be true.
I don’t know if we possess abilities like this or not, but it’s interesting to contemplate. What’s even weirder is that you can imagine a species that lacks free will, but which is at some point able to install a machine into itself that gives it access to free will! I’ll have to write a sci fi story about that one day.
So, where does this leave us? Right back at the beginning, I’m afraid. As far as I’m aware, we can’t make a final judgment on either the necessary or sufficient conditions. Perhaps then Hitchens’ irony is entirely appropriate. We have a question we can’t answer. A question we may never be able to answer. So, we might as well have a laugh at it.