Friday, May 22, 2009

Is the discussion of free will an illusion?

Biologist Martin Heisenberg writes an article for Nature which purports to address the issue of free will, but ultimately does nothing of the kind.

Heisenberg describes the actual research around which the article is constructed, as follows:

My lab has demonstrated that fruit flies, in situations they have never encountered, can modify their expectations about the consequences of their actions. They can solve problems that no individual fly in the evolutionary history of the species has solved before. Our experiments show that they actively initiate behaviour. Like humans who can paint with their toes, we have found that flies can be made to use several different motor outputs to escape a life-threatening danger or to visually stabilize their orientation in space.

The 'expectations' of fruit flies?

Let us be generous, and accept that this term is used metaphorically. The problem with Heisenberg's article owes far more to the general thrust of the argument, which is merely to claim that animals are capable of adapting their behaviour, that "behavioural output can be independent of sensory input." Yet, as Heisenberg admits himself, "the idea that animals act only in response to external stimuli has long been abandoned, and it is well established that they initiate behaviour on the basis of their internal states, as we do." But given that this fact is well-established, it is difficult to see what Heisenberg thinks has been newly discovered in his lab.

Let us accept that Heisenberg's lab have correctly interpreted their empirical data, and that fruit lies are indeed capable of adapting to their environment. This would constitute a type of learning, but it is difficult to see how this bears upon the issue of free will. Neural networks, for example, are capable of learning, and there is a body of literature which demonstrates that recurrent neural networks can be trained to behave like deterministic finite-state automata (DFA). Fruit-fly learning and subsequent behaviour could be represented by such a neural network, but a neural network that can be trained to behave like a DFA is hardly considered to be the epitome of freely-willed behaviour. Neural networks themselves can be either deterministic or stochastic (i.e., random), but both types of causation are distinct from Heisenberg's notion of freely-willed behaviour as "self-generated," (i.e., neither determined, nor random).

If fruit flies are indeed capable of adapting to their environment, then this would be inconsistent with a behaviouristic interpretation of fluit fly behaviour (i.e., an interpretation which denies that fruit flies possess internal states), but it is perfectly consistent with a deterministic interpretation of their behaviour (as well as being quite irrelevant to the issue of free will). Without internal states, there can be no variation in the output response to input stimuli, but with internal states, the response to a stimulus can vary depending upon the internal state, and the internal state can be the result of prior learning.

So Heisenberg's lab have perhaps found evidence for the existence of internal states in fruit flies, but such a finding is of no relevance to the issue of free will.


Bob said...

I have no free will. I should get up and eat breakfast, instead I sit at the computerscreen and read blogs.

Ofcourse there is no such thing as absolute free will. If the complete history of my sensory inputs is known, if my own inner state is known, then my next decision is predictable. If it was not, then there should be something like an non-material mind. Which would be nice, but because of lack of evidence, I must reject it.

I will switch off the computer now. I will. Now.

Gordon McCabe said...

Indeed. Freely-willed conscious decision-making processes are simply special types of brain processes. If the brain is a wholly deterministic system, then such decisions are determined, whilst if the brain is a partially random system, then such decisions could be partially random.

Any concept of free will is merely an epistemological concept rather than an ontological concept, but post-Augustine, the concept of an ontic free will is part of Christian dogma, and it continues to be an axiom for religious thinkers.

The Dandy Highwayman said...

Arguments and assertions concerning the existence of free will often strike me as somewhat pointless. I have not really analysed it properly but it all smacks of a category mistake. Surely even if in some sense we are deterministic, we must continue to treat ourselves and others as if we possess free will. It does not really matter that ontic free will has no scientific justification, the concept of free will still has an ethical value.

People who get all worked up about free will seem to miss the point. I can reasonably think that a person is a good person without believing that physical analysis would reveal that he is composed of goodness-particles. Similarly, I can reasonably make ethical decisions based on the assumption that I and others possess free will without needing to postulate that we are composed in part of immaterial freedom juice.

Gordon McCabe said...

You can discuss free will completely independently of any ethical considerations; it is a metaphysical question rather than an ethical one, although clearly there are many people who believe that it is a metaphysical question with ethical implications.

Do we even have to treat people as if they possess free will in order to make ethical judgements? Suppose that the world is completely deterministic, and we know it to be so; some human actions could still be judged as good and some as bad, even though we know them to be the outcome of deterministic decision-making processes, and even though we know that our ethical judgements of those decisions are themselves the outcome of deterministic judgement-forming processes.

Clare Dudman said...

I agree with Bob. I have no free will either - although I like to think I have.

It is a hard thing to come to terms with, though, isn't it? The most conniving thief has no alternative but to steal; and the jury has no option but to find him guilty..or innocent.

It makes me wonder what is the point of anything.

See what you've done? I was perfectly happy until I happened to come here tonight. Now I know I have no free will and everything is pointless. Ugh. I need a drink.

The Dandy Highwayman said...

Sorry, I did not express myself very clearly. What I meant to say was that many arguments I have read concerning the issue of free will are not, in fact, metaphysical arguments but rather ethical arguments. They confuse the issue by dressing up their moral preferences in terms that suggest a rational, metaphysical argument.

You claim that you can discuss free will completely independently of any ethical considerations. That may be true but most discussions of free will (at least, those that I encounter while I while away my time trawling the internet) seem to be very much entangled with ethical considerations.

I claim that you can discuss the ethical implications of free will without the need to also answer any ontological questions. I also claim that we really do have to treat people as if they possess free will, regardless of any ontological arguments.

You wrote, "Suppose that the world is completely deterministic, and we know it to be so; some human actions could still be judged as good and some as bad..."

I think you are conflating two different meanings of good (and also of bad). On the one hand we have a moral judgment, on the other we have a preference for a certain outcome. Those are not the same thing.

I believe that it would be good if it were to rain before the grass on my lawn dies. However, I am not making any moral claim by expressing that belief. Similarly, it would be bad if a large volcano erupted and killed thousands of people but that wouldn't mean that the volcano was morally bad.

To be morally good or bad one must be a moral agent; that is to say, morality applies only to those capable of making moral judgments, i.e. those with free will.

An animist may consider a volcano evil, but only to the extent that he believes it to possess a spirit capable of moral judgment. I'd be surprised to hear a modern Westerner describe a volcano as evil.

Grinnyguy said...

As far as I'm concerned, the assumption among some people that we have free will is very odd. But it's hard to be cerain that we don't.

It certainly feels like we do, but there isn't much evidence for free will as far as I can make out.

I do think it has ethical implications though. Take prisons, for example. If prison is a punishment, that is unfair because they never had the choice of doing anything other than breaking the law. However, we can think of a better aim for prisons. It is a means of altering a person's internal state so that they do not commit the crime again (with as few other consequences as possible - such as physical pain, personality changes)

This and other examples show that a discussion of free will has implications beyond the academic ones.

Gordon McCabe said...

But how do you reach the claim, DH, that a moral agent, or an agent capable of making moral judgements, must be treated as if they possess free will?

We certainly need to distinguish between the conscious decision making processes of cognitive systems and the inanimate or unconscious behaviour of natural phenomena such as volcanoes, but the notion of a moral agent is perfectly coherent without invoking a dubious ontological concept such as free will.

There is, however, an epistemological concept of free will, and it may be that this is what you're getting at. Even though our conscious decision-making processes may be deterministic, we don't know what we're going to decide until we go through the process, and individuals capable of being in this epistemological condition are clearly distinct from inanimate and unconscious systems.

Gordon McCabe said...

GG: Even if we suppose that people's conscious decision-making processes are deterministic, it doesn't follow that the criminals in prison didn't have a choice. Most did have a choice, and chose to perform criminal acts. They went through decision-making processes, even if the outcome of those processes was determined. The origin and implementation of the justice system, and the incarceration of criminals, is then itself the outcome of other deterministic decision-making processes, and whether people judge it to be unfair to imprison criminals (with or without the hope of reform), is the outcome of deterministic judgement-forming processes.

The Dandy Highwayman said...

But how do you reach the claim, DH, that a moral agent, or an agent capable of making moral judgements, must be treated as if they possess free will?So far, I suppose I have defined "moral judgement" as a freely chosen ethical decision, which I admit is cheating as it rather begs the question. It is my intuition that it is free will that makes something a decision rather than merely an occurrence. I'll see if I can better justify my intuition.

We certainly need to distinguish between the conscious decision making processes of cognitive systems and the inanimate or unconscious behaviour of natural phenomena such as volcanoes...So how do we make that distinction? I am currently unable to distinguish between the inanimate behaviour of natural phenomena and the deterministic decision-making processes that you have described. I think your answer to this is the epistemological concept of free will:

Even though our conscious decision-making processes may be deterministic, we don't know what we're going to decide until we go through the process, and individuals capable of being in this epistemological condition are clearly distinct from inanimate and unconscious systems.However, I'm afraid what is clearly distinct for you is not so clear for me. What's the difference between not knowing what I'm going to decide and not knowing what the volcano is going to do?

Gordon McCabe said...

On the last question, the difference is that you can know what the volcano is going to do (if you have the necessary tectonic understanding and, say, seismological data), but it's not possible to know what your own decisions are going to be because self-knowledge can never be complete. If you knew what you were going to decide, it could change your decision, hence you cannot know what you're going to decide!

(Excellent contributions, as always DH).

Anonymous said...

I don't think the question of whether we have free will is metaphysical. I think it is a scientific one, but impossible to answer. If you have the time and patience please read the following argument:
We have a question, does free will exist or not?
We have two answers, with no possible third option:
Yes, or no.

1) If YES, then that means that either the particles (atoms and molecules) of the human brain have the spectacular behavior of defying laws of physics in order to lead to events which ultimately result in the satisfaction of the brain-owner, OR that the laws of physics themselves are not deterministic and they do leave a window open for random events to happen.

2) If the answer is NO, then what that means is that the particles of the human brain have to obey a set formula all the time, no exceptions made, ever.

A) but if "1" is true then it is impossible to confine the defiance of matter or the randomness of laws of physics to the spatial boundaries of the human brain. It must happen everywhere. Particles must defy laws of physics everywhere. Therefore any attempt to devise an experiment to measure how they behave will ultimately fail.

B) and if "2" is true, then it is impossible for a subset of particles to make an absolutely accurate measurement of the whole set, i.e. it is impossible for human brains, a subset, to devise an experiment that would produce an accurate measurement of the whole system.

Therefore it is impossible to determine whether we have free will or not.

Alright then, now I'm off to the pub :)

Gordon McCabe said...

Anon: In this context, I was using 'metaphysical' in contradistinction to 'ethical'. Note that science comes with its own metaphysics.

Advocates of free will often tend to speak of freely-willed behaviour as that which is neither determined or random, but 'self-generated'. There seems to be no coherent notion of what this means, but it does seem to imply that many such advocates are implicitly working with the notion of the self, (and often the soul), as the classic 'ghost-in-the-machine', pulling the levers of the brain, but also somehow operating outside the causal constraints of the physical world.

There is, however, one possible means of making this notion coherent: one might argue that the conscious self is an emergent phenomenon, supervening on the brain, and that there is downwards causation from the emergent self to the lower-level brain processes. This might be said to be self-generated behaviour: the properties and behaviour of the subsystems of the brain are modified by the properties and behaviour of the emergent mental self, which the brain subsystems themselves jointly determine.

The notion of downwards causation, however, is either incoherent or superfluous. If the brain properties and processes determine the mental self, and the mental self is then the cause of a change in the brain properties and processes, one can dispense with the mental self as a link in the causal chain and simply speak of one brain state causing another.

The Dandy Highwayman said...

I apologise for the formatting of my last comment: some line breaks that appeared in the preview seem to have disappeared in the comment itself. I blame Blogger.

Anyway, so you cannot accurately predict your own decision-making processes as any such prediction would become an input to the decision-making process and so invalidate the prediction. That seems fair enough.

However, there's no reason why someone else, equipped with the appropriate theoretical understanding and the necessary technology, could not predict your future decisions just as he could predict the actions of a volcano.

So, in the context of moral judgements, you appear to be defining 'to decide' as 'to undergo a physical procedure whose outcome you alone could not possibly predict'. Is that a fair assessment of your position?

I suppose that is indeed a well-defined state, distinct from that of a volcano which is unable to predict anything, but I don't see how it can entail moral responsibility.

In order for someone to be responsible for their actions, surely those actions must in some sense be self-generated? Is that not what we mean by the term 'responsible'?

I don't think it bothers me that morality and other "human phenomena" require us (as I claim) to posit the existence of things such as free will for which there is no scientific justification. It's just a feature of the way we work. Evolution is a blind process with no ability to plan for the situation in which an organism analyses those instincts and modes of thought which it has evolved. It does not seem improbable to me that we could have evolved patterns of social behaviour and methods of thinking that assume artifacts that do not physically exist.

Gordon McCabe said...

I was trying to define the epistemological notion of free will, DH, rather than trying to show how moral responsibility follows from it. In fact, I don't think that the unique epistemological condition of self-conscious decision-making cognitive systems does entail moral responsibility.

It should also be noted that the epistemological notion of free will requires more than mere decision-making capability, because an expert computer system possesses the latter. It requires the reflective nature of self-consciousness in addition to decision-making capability.

I would agree with the last statement that "we could have evolved patterns of social behaviour and methods of thinking that assume artifacts that do not physically exist." My argument, however, is that there is no need to treat people as if they possess free will (in the ontological sense) in order to treat them as moral agents; we merely need to identify them as fellow self-conscious decision-making cognitive systems. I don't think their status as moral agents follows from the fact that they are such systems; rather, I agree with you in the sense that it is more an instinctive part of our socio-biology.

The Dandy Highwayman said...

That's a good point.

I suppose I can't have my pseudo-theological deduction of moral responsibility from one's status as a moral agent at the same time as I explain away the necessity to posit unscientific entities as an artifact of our evolved socio-biological systems.

While we're on that topic, I just found some remarkably good carrot cake in the café downstairs. I ate it while reading Tolkien's letters to his son Christopher. Annoyingly, I don't have it anymore.

Gordon McCabe said...

I've never really 'got' carrot-cake. I can never get beyond the name; lumps of carrot embedded in a sponge? Same thing with cauliflower: why would you want to eat a flower?

The Dandy Highwayman said...

I agree that carrots are an absurd ingredient for a cake. When I first encountered carrot cake I naturally assumed that it was just one of those names - like how toad-in-the-hole does not actually contain toads - for surely no-one would be insane enough to really bake a cake with carrots in it!

It came as quite a surprise when I discovered, a good decade or two later, that carrot cake really does have carrot in it. However, by then I had many years of delicious cake eating experience to overrule my initial reaction of confused disgust.

Carrot cake, it turns out, is actually a wonderful invention.

Bob said...

Even if a criminal did not have a choice, it is still a good idea to put him in prison. If only for the reason that while he is in prison, he cannot commit any more crimes. And surely for a lot of people the concept of prison will prevent them of committing any. It is al determined up front, but it stil works. It is a little confusing, I admit;

This is why I talked about absolute free will. The 'free will' in an ethical context is based on someones personality: given a number of options, what does he decide to do? If he decides to go stealing or mobbing, then this is a result of his personality and/or his background, AND the consequences of his actions that he considers (e.g. prison).