Saturday, 25 August 2012

Free will: Misconceptions answered

Having established the problems with reductionism, and having established a need to explain the 'world' of abstract ideas on a higher-than-deterministic level, let's turn to some of the more common determinist and compatibilist claims about free will.
An action is only free if it was possible to do otherwise. Our thoughts consist of activity in the brain, which is a purely physical phenomenon. Physical activity is either random or deterministic – so our thoughts are either physically inevitable (determined) or controlled by random factors. Neither of these allow for free will.
For a start, this isn't very helpful in itself. Like solipsism, it merely proclaims the non-existence of something, not because it's a bad explanation, but just because of an apparent logical difficulty. It denounces a host of experiences as illusory, closing off the possibility of finding better explanations for them. It's not a good approach.

It's also a reductionist argument. It assumes that people's choices must be explained in terms of low-level interactions, as if this form of explanation were more 'fundamental'.  Even if we did know all the (inconceivably many) physical events that led to a certain thought, they wouldn't be a good explanation of why the person had that thought. If I think to myself, 'I need to write a blog post', the reason I had that thought could be explained as, 'Because X neurons fired off in Y and Z locations' – but this only tells us what physically prompted my thought.  It was already clear that neurons needed to signal in order for me to have had a thought. So it tells us nothing we didn't know already.

Fine, some stuff is emergent. But still, every effect has a cause. Even if my thoughts and actions are caused by emergent ideas and circumstances, according to causality they're still unavoidable. So for every decision I make, I couldn't have done otherwise.
People are creative. Ideas change, technology progresses, all the time people form new theories in the light of criticism. It doesn't make sense to talk about creativity in terms of sufficient causes, because if a new idea could be inferred from something that went before, that thing would contain the idea – and so it wouldn't be new at all. The future is unavoidable only on a lower level of explanation with respect to that of knowledge-creators. On the abstract level of creative thought, causal determinism isn't applicable. It is true that there is always a single answer to questions about what *physical* state something will be in in the future. Physically it is determined. But on the emergent level of knowledge creation the future has to be open.
But you don't know what your thoughts are going to be before you think them. And you can't be in control of something if you can't predict what it's going to do, surely. So how can you be in control of your thoughts?
Again, if you could predict your own thoughts, those predictions would be the thoughts themselves. There's no real reason to think you can't be in control of a thought as you're having it, though it didn't occur to you to have it beforehand. We pursue certain trains of thought purposefully: we can freely intend to come to a conclusion without knowing in advance what the conclusion will be. This doesn't imply a lack of control; it just implies creativity.
People are free in the sense that they have evitability: They can alter their courses of action according to projected consequences. Even if at the micro-level we are behaving deterministically, we're still free in the sense that matters.
This view of free will would mean that a simple computer program could have a little bit of that which makes humans free. It is true that computers can be programmed to follow abstract rules, such that their activities couldn't be explained in purely physical terms. But human freedom is on a higher level of emergence than that, because of creativity. If we were 'free' in the same way as that computer program, just to a higher degree, our actions would be predictable in principle and hence determined. So there's more to it than having purpose and 'evitability'.

Tuesday, 7 August 2012

Free will emerges

Free will and notes on The Beginning of Infinity, Chapter 5
Arguments against free will tend to make the reductionist assumption that, because there isn’t a physical explanation for human freedom, it must be an illusion. Broadly, reductionism is the idea that the world can only be explained as the sum of interactions of its fundamental parts. For example, the high-level properties of a substance (such as boiling point or state at room temperature) can be predicted from low-level atomic interactions. Lots of these sorts of ‘reductive’ theories are true and useful; they have reach. Newtonian mechanics was a ‘reduction’ of Kepler’s laws of planetary motion and Galileo’s theories of motion. But reductionism as a methodology is mistaken. Science doesn't progress by analysing high-level phenomena into low-level phenomena. There are lots of high-level phenomena that, while they ultimately consist of low-level phenomena, have patterns and laws that are present on the higher level but not, so far as we know, on the lower level.

Douglas Hofstadter gave the following as an example of the inadequacy of reductionist explanations for emergent phenomena. Imagine a set-up of millions of dominoes, placed closely together (so that they can knock each other over in the usual way) in a complex pattern of rows. The dominoes are spring-loaded and, if knocked over, will pop back up after a set time. If a row is knocked over it can be interpreted as a binary ‘1’, and if not knocked over, a binary ‘0’. The set-up is sufficiently rich and complex that it can perform computations, and in this instance it is set up to tell you whether the number keyed in (by placing a row of that number of dominoes at a specified position) is a prime. One domino in the set-up is the output domino: If it is knocked over at the end of the computation, it means a divisor was found and hence the input number is not a prime. If it stays standing, the input number is a prime.

Now, if the output domino stays standing after one of these operations, an observer may single it out and ask: “Why did that domino never fall?” The reductionist explanation would be: “Because the domino behind it never fell, because the domino behind that domino never fell, because…” – and so on, or: “Because none of its neighbours ever fell, because none of their neighbours ever fell,” and so on.  This answer is true, but it is not an explanation: It merely states the already obvious fact that no domino will fall unless one of its neighbours falls. To explain why the domino didn’t fall, we have to make reference to the non-physical concept of primality and to the dominoes’ emergent capacity to say whether a given number is a prime.
So reductionist 'explanations' are inadequate for some emergent phenomena. Even if the series of physical events described by the reductionist account did actually happen, such emergent patterns have to be explained on their own terms. If human freedom is emergent, it doesn’t conflict with physical determinism -- it just has nothing to do with it.

There is a reductionist idea that the mind cannot affect the physical world, on the grounds that only physical events can cause other physical events. But the idea of a ‘cause’ is abstract; at the purely physical level, cause and effect are interchangeable. The laws of motion can retrodict as well as predict. So a cause is just an explanation we infer for why something happened, and there is no reason to think that physical explanations are the only explanations we have.

For more, see David Deutsch, The Beginning of Infinity, Chapter 5.

Popper’s three Worlds

To describe the emergence of human knowledge, Popper posits three worlds -- World 1, the world of physical events; World 2, that of mental states or subjective experiences; World 3, that of products of the human mind: theories, scientific (or otherwise intellectual) problems, the information (if not the physical stuff) in books and libraries. It used to be popular to deny the existence of World 1 and to claim that only subjective experience exists. Now it’s more fashionable to claim that only the physical world exists and to deny the existence of experience. The once-popular denial of the reality of World 1 was refuted by Dr Johnson on the grounds that it ‘kicks back’. If the physical world is an illusion, and that illusion behaves exactly as though it were real, then it needs to be understood and explained in exactly the same way as would a real physical world. It kicks back, and so it might as well be considered real.

To explain the physical (World 1) presence of man-made objects -- say, skyscrapers, computers, nuclear reactors -- we have to refer to the theories people formed about how to produce them. These World 3  theories could also be mistaken. A miscalculation might lead to the World 1 event of a bridge collapsing. World 3 has a logical structure that exists independently of humans. For example, though natural numbers are a human invention, facts about them can be discovered, such as the existence of primes.

The ‘human’ dimension of World 3 also kicks back. We make judgements about people’s beliefs, values, habits, etc., and explain their actions as responses, based on those things, to a given set of circumstances. I might be convinced that my boss is going to sack an incompetent colleague, but then discover that, because my boss is the forgiving type, the colleague has instead been put on a training programme. Using the laws of physics to explain all of these things reductively would be absurd. It would be as much as to say that they don’t exist, even though they kick back. If someone thinks that 4+4=9, he will be kicked back by the laws of mathematics. Similarly, (and quite rightly), people who deny the existence of free will are kicked back by the contradiction inherent in proposing such arguments as things that people ought to favour (to choose) over other theories.

For more on the three Worlds, see Karl Popper, The Open Universe, Addendum 1: Indeterminism is Not Enough.