Stephen Law (S.L.) What is ‘free will’? How do we know we have free will?

Helen BeeBee (H.B.) Well, we can only know we've got something if we know what we're looking for, and part of what the free will debate is about is, precisely, what free will is. You might think of having free will as being a matter of having a kind of unconstrained choice about what you do: your freely ordering the lasagne rather than the pizza requires that you could have ordered the pizza instead. Or you might think of it as having a kind of control over your actions (both your mental actions, such as decisions, and your physical actions): if you're acting freely, what you do is fully under your control. Your action isn't just random or instinctive; it's something that you brought about, something that stems from reasons for acting in that way, something that makes sense in the light of your goals and desires and beliefs.

That said, it's not at all clear – and this is one of the major bones of contention – that those are really two different ways of thinking about free will. In particular, you might think that if you couldn't have chosen the pizza instead of the lasagne – if there was only one choice you could really make – then ordering the lasagne wasn't really under your control. Most philosophers agree that acting freely requires that your action is under your control; but they disagree a lot about what that requires, and in particular whether (or in what sense) it requires that you could have done something else instead.

S.L. How does free will relate to moral responsibility?

H.B. That's another thorny question! Some philosophers – and I'm one of them – think that free will is basically the ‘control condition’ on moral responsibility, as it's sometimes put. What kind of control do I need to have over my actions if I'm to be held accountable for them, so that it would be appropriate to praise me if I do something good and blame me if I do something bad? Whatever that kind of control is, that's what free will amounts to. (What is that kind of control? That's a hard question. The kind of control a well-trained dog has isn't enough. The kind of control God would have over his actions is more than we need. So something in the middle.)

On the other hand, some philosophers take the question of what free will is – and whether or not we have it – to be a question of pure metaphysics. The question would make perfectly good sense, they think, even if human beings had never developed any kind of moral sensibility at all – if they'd never gone in for the practices of praising or blaming, or felt any kind of moral emotion or attitude, like shame or guilt or resentment or forgiveness. From my point of view, though, the question – what is free will? – wouldn't really make sense in that scenario. Such humans would have certain kinds of control and not others. Some of them would have kinds of control that others would lack. Fine. Which out of kinds of control would be the kind that constitutes free will? I just don't see a non-arbitrary way of answering that question. The connection with moral responsibility is what gives the question about free will not just its importance but its meaning.

S.L. In setting up the ‘problem of free will’, philosophers usually refer to something called ‘determinism’. Could you briefly explain what determinism is, why we should think determinism is true, and why determinism might seem to pose a threat for free will?

H.B. The basic idea of determinism is that – in principle – the entire Universe is completely predictable. If only we could write down all the basic laws of nature, and plug in the entire state of the Universe at a particular time, we'd be able to derive from that exactly what's going to happen in the next ten seconds or the next twenty minutes or, for that matter, the next billion years. Of course we'll almost certainly never know all the basic laws, and we could certainly never know the exact state of the entire Universe at a given moment, but that's not the point: determinism is the thesis that those two things imply all the facts about what will happen in the future.

We don't know whether or not determinism is true – the evidence as it stands is that it probably isn't – but it's often thought that determinism is incompatible with free will. So if the Universe is deterministic, nobody ever acts freely. All of our behaviour – including when and how we scratch our noses, what pops into our heads, what we decide – all of it – is the inevitable result of facts about the distant past, which of course we have no control over, and the laws of nature, which we also have no control over. And since we don't have any control over those things, we surely don't have any control over what they imply. Or you could put more or less the same problem in terms of being able to do otherwise, as per the thought that I ordered the lasagne but I could have ordered the pizza instead. If I was determined by the state of the entire Universe a hundred years ago (or a billion years ago, or whatever) to order the lasagne, then surely that was the only thing I could have done. I couldn't have ordered the pizza, even though it seemed to me, before I decided on the lasagne, that that option was genuinely open to me. It wasn't really open to me at all – it just seemed that way because I didn't know all of the facts that implied that I'd go for the lasagne.

S.L. What's a good way of setting up the problem of free will in a nutshell – just a few premises and a conclusion?

H.B. Well, this is loosely based on Peter van Inwagen's famous ‘Consequences Argument’:

Premise 1: Helen ordered the lasagne at time t.

Premise 2: If determinism is true, then facts about the state of the Universe at some time in the distant past (call that ‘time t-minus’) plus facts about what all the laws of nature are entail that Helen ordered the lasagne at t.

Premise 3: If someone has no control over some fact X, then they have no control over any fact that X entails.

Premise 4: Helen had no control over the state of the Universe at t-minus; nor did she have any control over the laws of nature.

Conclusion 1: So if determinism is true, Helen had no control over ordering the lasagne at t.

Premise 5: Doing something freely requires having control over doing it.

Conclusion 2: So if determinism is true, Helen did not order the lasagne freely.

And of course you can substitute any person, action and time you like for ‘Helen ordered the lasagne at time t’ and the argument will run just the same. So the ultimate conclusion is that if determinism is true, nobody ever acts freely.

Van Inwagen actually sets it up not in terms of control but in terms of the ability to do otherwise. Another – related but distinct – way of putting the problem is in terms of ‘sourcehood’: according to some incompatibilists (that is, people who think that free will is incompatible with determinism), the problem with determinism isn't that it renders us unable to do otherwise but that it means we can't be the ‘ultimate sources’ of our actions. The deterministic chain running back in time from your action to its causes to the causes of their causes and so on runs right through you and back out the other side. So the ultimate ‘sources’ of my ordering the lasagne lie in the distant past, way before I was born. And – so such incompatibilists claim – that means that the buck doesn't stop with the agent. Which is where – allegedly – it would need to stop if we are to have the kind of control over our actions that moral responsibility for them requires.

S.L. What are the leading solutions to the problem of free will? Which do you favour, and why?

Well, the argument above leaves us with various options. You can grant that the argument is valid but deny determinism – that's the route that so-called ‘libertarians’ take. Or you can grant that the argument is valid and embrace determinism – and hence embrace the view that there's no free will. That's the route the ‘hard determinists’ take. Or you can find fault with the argument. That's what ‘compatibilists’ need to do – people who think that determinism is no bar to acting freely.

Compatibilists have come up with all manner of moves to get out of the argument, but – as I said before – the basic issue is the notion of ‘control’. Compatibilists think that (in normal circumstances anyway) we do have the kind of ‘control’ over our actions that is required for acting freely. As I said, what ‘control’ amounts to is a thorny issue. Some compatibilists agree with van Inwagen that the kind of control that's required is the ability to do otherwise, but they argue that the ability to do otherwise doesn't require the falsity of determinism. The way I just set up the argument, that amounts to straightforwardly denying Premise 3. I say ‘straightforwardly’, but you have to come up with an account of the ability to do otherwise that is compatible with determinism – and that's a tricky business. One way to get the basic idea, though, is to think about dispositions, such as fragility or laziness. When it comes to ascribing fragility to a glass – roughly, the disposition to break when dropped – or laziness to a person (the disposition to, say, take the car to the station rather than walk even though it's only five minutes and you're perfectly capable of walking), the truth of determinism is neither here nor there. Compatibilists of this kind take the ability to do otherwise as a kind of disposition – I was able to choose the lasagne, even though I was determined not to, just as the glass is disposed to break when dropped, even though it was safely on the shelf and was determined just to sit there and not fall off.

Other compatibilists concede that the ability to do otherwise is incompatible with determinism, but deny that the ability to do otherwise is required for control. That amounts to saying: ‘OK, if by “control” in Premise 3 you mean the ability to do otherwise, then Premise 3 is true – but Premise 5 is false, since that kind of control isn't required for acting freely. If, on the other hand, in Premise 3 you mean the kind of control required for acting freely, then, again, Premise 3 is false.’ Daniel Dennett once said something like: nobody thinks that the truth of determinism means that thermostats don't control the temperature. His point was that there is at least a perfectly ordinary sense of ‘control’ that nobody takes to be incompatible with determinism. Of course, thermostats don't act freely (or indeed at all). But in his view, human beings are different from thermostats only in that we are far more sophisticated. A thermostat is sensitive to exactly one thing – the temperature – and it can only do exactly two things: turn the heating on or off. By contrast, we are sensitive to a vast array of different circumstances, and in particular to our own beliefs and desires; and we can do a lot of things. I can control my own temperature by putting on or taking off a jumper, but I can also control how hungry I am by eating, I can control whether I keep my promises or walk to the station, and so on. But the basic notion of ‘control’ when it comes to our own actions is pretty much the same as the notion of control that we apply to the thermostat, and so our control over our actions is no more threatened by determinism than is the thermostat's control over the temperature.

I guess I am neutral between both of those compatibilist responses. Or rather, I'm fine with the Dennett approach. But if you really want to insist that acting freely requires the ability to do otherwise, I'll just point you at the compatibilist-friendly accounts of the ability to do otherwise. What's crucial for me is that whether or not determinism happens to be true just doesn't matter for moral responsibility. Our practices of praise and blame, reward and punishment, are completely insensitive to whether or not they are determined – and so they should be. What matters is why you acted as you did. When you blanked me in the street, were you sleepwalking, or did you not notice me waving at you, or did you just not recognize me? Those things would all get you off the hook. If the laws determined that you deliberately and maliciously snubbed me, well, that does not get you off the hook.