Free Will



A few social media debates on the subject of “free will” have interested me recently (in January 2023). The debate is basically, “Do we have free will?” If this has passed you by you might think it’s an odd thing to debate. In essence, there are people who say that we don’t have free will; we are just automata, programmed to do the things we do by impersonal physical forces. This is so strangely contrary to everyday experience that they must have strong reasons for the assertion and my purpose in this essay is to examine what those reasons are as well as whether there’s anything in the idea.

Although it’s easy to say “We have free will” or “We don’t have it”, it’s not so easy to be sure what these statements mean. What is free will? The usual statement of freedom is along the lines, “In a choice between actions A and B, I did A, but in exactly the same situation I could have chosen to do B”. “Actions” extend to the things we say and even what we think as well as physical actions, and by “exactly the same situation” is meant not just a simple repetition, but the whole universe having the identical configuration; so the choice really comes just once. Doing A then B doesn’t demonstrate the claimed freedom because the universe was subtly different the second time.

That’s the usual definition in this debate, and it has to be said that there are some problems in it. The whole claim is based on things I don’t do. I did A; I could have done B, but I didn’t. This can never be tested because the chance to do B instead of A in that exact situation will never come again. No-one will ever have the chance to see me choosing to do B, so what does it mean to say I could have done it? It’s even more tricky with thoughts: “I thought of A, but I could have thought of B…”; “But wait, you just did! Or did you?”

This definition of free will is logically consistent but it can never be tested even in principle. Later I’ll suggest a way of making a more useful definition.

Why would anyone want to suggest that we don’t have free will? The idea usually comes from a particular interpretation of science. As soon as Newton, Laplace and others began to develop the description of the universe in which everything is made up of particles which move according to physical laws, the problem posed by this description was apparent. These particles don’t have any choices, they just have to follow the laws. So if we’re made of such particles, we don’t have choices either. Ah, maybe we’re thinking beings? But either our brains are also made of those choiceless particles, or we are spirits which have no way of controlling them. To change the behaviour of our bodies by thought would mean breaking the laws of physics which the particles making us up must obey. The whole picture makes us seem like clockwork creatures, very complex maybe, but in the end completely predictable.

This is a bleak picture. It seems to exclude morality. What credit is due to me for doing anything good if I was unable to do otherwise? Why should I be punished for a crime if I was unable not to commit it? Whatever I may have done, right or wrong, it was only because of the unbreakable laws which my brain and body have to obey.

So why would anyone accept such a bleak picture? The first reason is the emphasis on deterministic physical laws which I’ve mentioned. Coupled with this there’s a metaphysical viewpoint. This view of science is essentially an atheistic one. Its proponents are alive to the possibility that one possible escape is to postulate a non-material soul or spirit which lives in us, giving mind to our brain and controlling some of the matter which composes us by non-physical means. But once they allow soul or spirit into their world-picture, it becomes difficult to definitely exclude God! To exclude Him, they’re willing to pay the price: deterministic science controls all; everything is just matter; even our thoughts aren’t really under our control. That’s where this whole debate originates, and it’s a metaphysical motivation, not a scientific one.

This deterministic picture has the disadvantage of being contrary to experience. Every day in innumerable ways we all make choices. We choose what to eat, where to go, what to do, who to meet and what to say to them. Our thoughts do control the movements of our bodies. We’re very clear about the fact that these actions are choices made by us. This is true for materialist atheists as well as the rest of us. On a practical level no-one can really live day-to-day believing they’re just a clockwork mechanism. The usual explanation (in “strong determinism”) is that we are just spectators. We think we are making these choices, but really they are just the results of physical laws. Our strong belief that we’re making choices is also just another result of those laws working on the matter in our brains. We could have done nothing other than what we did, even if we think otherwise. The brain’s role is more one of constructing a narrative explaining what we do rather than making choices about it. Yes, this is extremely counter-intuitive, but to some it’s a price worth paying.

I would actually say that this is an unscientific attitude. Science should follow observations, not seek to reinterpret them. Even without doing any “scientific experiments”, a key starting observation for me is that I’m conscious, I have intentions and I make choices. My thoughts animate my body. Real science will start by acknowledging these observations and building them into further discoveries, not try to explain them away. As Descartes said, “I think, therefore I am”.

There’s an even bigger disaster lurking here for science, but before I go into it, let me mention a couple of possible escapes from determinism. These days Newton doesn’t have the last word. To correctly predict what all the particles in the universe will do next, we can point out that an infinite amount of information would be required. We would want the coordinates, speeds, spins etc. of every particle. To record all this information accurately could require storage as big as the universe! Modern Chaos theory adds to the storage required by pointing out that all those pieces of data would be needed with infinite precision, so actually every single parameter would require infinite storage. Any attempt to introduce approximations could change the results out of all recognition. Finally, there’s Quantum Mechanics: particles aren’t really as simple as Newton thought and in some situations they can behave as if their positions or movements are undefined. All this doesn’t really provide free will though; introducing some randomness or uncertainty doesn’t mean we get to make choices among possible alternatives. (Unless we suspect that minds are in some way “quantum agents”; that’s an interesting contemporary speculation which I won’t go into now).

Well, what’s the really big issue in all this for science? Basically, this: if I assume determinism I seem to have a situation in which two individuals can hold different opinions about a subject, and both of them have their opinions given to them by impersonal mechanistic effects from the chemical reactions in their brains. Let’s say that one of them thinks “The sky is blue” and the other thinks “The sky is yellow”. Both of them also have the illusion that they’re free and able to assess the things they’re thinking about. How can we decide who is right?

This dives into a huge area of philosophy around the question, “What is truth”? How can we define truth? Philosophers offer various answers to this and I’ll go with the one which seems common-sense and is also popular in science: a statement is true if it corresponds to what’s real. So with those two thinkers above, we could observe that the sky is blue and say that, even though they both think they’re right, actually the first one is right and the second one is wrong. This point of view is good for science because it provides a clear role for observation and experiment.

But there’s still a big problem; really big. Who decides what corresponds to reality? We might think that we can just look at the sky, see what colour it is and decide which of the two thinkers is right. But we’re in the same boat as them! If we’re also deterministic, our thoughts about what we’ve seen in the sky are also the product of mindless chemical reactions in our brains. We might be deluded; our inner narrative would never know it. It will be complete accident for us to agree with one thinker or the other.

What this comes down to is, if we’re such limited beings, with deterministic thoughts, no real choices and only an illusion of freedom, we cannot do science. This view is a disaster for any kind of conversation based on observations and notions of truth. There is no reason why containers of complex chemical reactions should ever be able to discover anything about reality, although they might “think” they have.

What's more, it’s always illuminating to take an idea and ask, “What does it say about itself?” Let me revisit those two individuals and suppose that they’re now thinking, “We don’t have free thought” and “We do have free thought”. If the first one is right, we don’t have it and, again, we’re not the kind of beings which can really know anything (although we might think we do). If the second is right, there is a chance that the two of them can do some observations, talk it over and reach an agreement (of course, they might still slip up somehow and conclude that the first is right!) But from our point of view, why would we ever take any notice of the first thinker? He’s saying that whatever he thinks he knows cannot be checked; he has no way of being sure that his thoughts align with reality. So at the same time as telling us that we don’t have free thoughts, he’s also telling us we needn’t believe him! His words are contradicting themselves and therefore don’t carry any meaning. He can be safely ignored.

But I said I’d offer a better definition of “free” and find an escape from all this. To do that, I’m going to go back and base things on the definition of truth and the method of science, which is pre-eminently our best method for finding out about the natural world. So a statement (a scientific theory even) is true if it corresponds to reality. We find out what corresponds to reality by the methodology of science, which typically works in stages:
My proposed escape from the confusion is this: to do science we must accept that we are the kind of creatures capable of doing science. Some of the justification for the “no free will” idea seems to be from an interpretation of science, but if we’re using science we have to accept that it means something and that human beings can learn from it successfully. Now it’s clearer what having free thought must mean: I have real choices about what to think; I’m capable of deciding what observations mean; I’m able to use logic and rules of inference to assess observations and form hypotheses; I’m capable of deciding whether an idea corresponds to reality – whether it’s true. If all this isn't the case, nothing can be learned from science.
I can therefore define “free” like this: my thoughts cannot be just a by-product of chemical reactions. They correctly embody logic and its rules of inference, and they're under my control to direct as I see fit. This is not an illusion. There’s no reason why chemical reactions in my brain should embody these things, so thought isn’t solely produced by those reactions. (Once I’ve asserted the necessity of free thought, free will won’t be a problem; I can think about what to do at every moment). OK, I might still slip-up and misinterpret observations and I’ll never be able to know everything, but at least I can get started.

I have to stress that this isn’t a preference. It’s not what I want or choose to be true. It’s what must be true before beings like me can find out anything. It’s what’s called an axiom. Without this view of thought, science is impossible and nothing can be known. Anyone who says it isn’t true is essentially contradicting themselves and has nothing meaningful to say.

As this is an axiom I have no way of proving it; proof just isn't a thing that applies to axioms. To give another example, in Euclid’s geometry there’s a starting axiom that, given any two points, a line can be drawn between them. You can never prove that this is true using geometry, but if it isn’t true there’s no such thing as geometry.

However, in the case of science I think I can make an argument for plausibility by pointing to how successful it is. Just think of how different our lives are to how they would have been in the stone age. Consider advances in medicine based on our understanding of how our bodies work. Think about the technological marvels available to us, including the devices we're using right now. See how far through space we've thrown our gadgets.  It's not plausible that our ideas derived from science are only right “by accident” and the whole enterprise really has no foundation in truth.

So if a piece of scientific work seems to say that we don't have the free will needed to do science, it has to be rejected. It's like the thing that may well have happened to you if you do much maths: after several pages of algebra you end up concluding that -1=1. The conclusion is wrong, and you don't need to go back over all the work to know that you've made a mistake. Finding the mistake might still be hard, but knowing that it's in there somewhere is easy. I take the same view of any interpretation of science which says we're incapable of doing science; it’s wrong because it says it is.
I know that there are some who won’t like this viewpoint. It will seem to let in the idea of a non-material soul or spirit which has some relationship to my brain and supplies the necessary freedom in my thoughts. Atheists won’t like this because, if a soul gets in to our world-view, what’s to keep God out? I make two answers to this. First, if we start to speak about a soul, I don’t know any more than anyone else. I’ve gone as far as I can by asserting that if we’re going to do science we have to be creatures which are capable of doing science. Using science I can’t deduce from this what’s going on “behind the scenes” on any non-material level where science doesn't look. Second, I’m not impressed by someone who's willing to deny the possibility of knowing anything just to avoid knowing about God! To try to knock away the foundations of science just to maintain a metaphysical prejudice seems to me very silly. It’s like the man up a tree sawing off the branch he’s sitting on. To such people I say, “OK, carry on sawing if you like, but don’t expect me to join you up there!”

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