How physicists handle the idea of Free Will?

John Creighto

When I think, doesn’t it change the state of the atoms inside my head? Therefore, don’t my thoughts directly influence at least a small part of the physical world? Therefore, the dynamics of particles depends on how particles are organized in the whole.

We might say though that I have cause backwards. However, the motion of these particles is dependent on fields. Fields are the result of how particles are organized. Well, in theory we may suspect that fields can be modeled as a consequential sum of the totality of particle effects. However, the calculation of such fields is not as interesting as the structure of the fields. It is structure which is the most important property of the whole.

There is a duality between the whole influencing the small and the small influencing the whole. A wave for instance is a macroscopic property. It extends though all space but a single particle can be described as a super position of waves.

The wave isn’t just an emergent property of the particles as even the motion of a single particle is described by a wave. Thus the large and the small are inextricably linked.

The mind is a property of the large and it’s properties are inextricably linked to the states of the particles within our body. Therefore, motion of particles in some regards is influenced by our thoughts. Thus in some way our thoughts influence the small. If thought is equivalent to consciousness then we should also expect consciousness to directly influence the dynamics of particles. If consciousness is not equivalent to thought then what is it?

Ferris_bg

Here are the four standard models of mind-body interaction.

If we accept that the mind is a property of the whole, then as you say at first it seems logical that the mind influences the whole. There is a however one problem with this assumption and its well illustrated by the Supervenience Argument from Kim. The argument points out that the non-reductive physicalism theories entail epiphenomenalism. If the mind supervenes on the physical, then it should be casually inert, if we accept that this is not a case of causal over-determination.

Consciousness is equivalent to intentional/cognitive properties ("thought" as you say) plus qualitative properties of consciousness (qualia) or C = M + Q. C is also unified, meaning that you can't separate M from Q or vice versa.

sophiecentaur

When we examine our mind, we are a system trying to analyse itself. We are bound to fail to come up with a complete explanation.
I commented earlier that consciousness and 'god' (/faith) are very similar. My thought is that our consciousness is probably closely associated with the need for a complicated organism to communicate with other individuals (huge evolutionary advantage). When we 'consider' a problem in our minds, we use our consciousness to 'discuss' the matter with ourselves rather like we would discuss with someone else. To communicate anything to another person, we often need to express it via our consciousness in order to assemble the words etc.. There are, of course, forms of communication between individuals which are not conscious - as there are between humans and other animals and between other animals. The message is then unstated and 'non-conscious' but it is not an 'intellectual' message that is passed.

ThomasT

The term free will is commonly used to refer to at least two things. One is that we obviously consider alternative courses of action. This isn't incompatible with determinsim. The other is that our actions could have, given identical antecedent conditions, resulted in different consequences -- or that, given identical antecedent conditions, we could have thought and acted differently than what we did. This is incompatible with determinism, and amounts to an assumption that our universe is evolving indeterministically.

There's no known quantum level of events. There's only, as far as can be objectively known and unambiguously communicated, a macroscopic level of events. The indeterminism of quantum experimental events is realized at the macroscopic level -- the level of instrumental behavior amenable to our sensory apprehension.

Not so wrt the macroscopic apprehension of quantum experimental events. Radioactive decay is random, unpredictable. Does that mean that nature is fundamentally indeterministic? Not necessarily. There's just no way to ascertain it one way or the other.

Not necessarily. As noted above. I believe in, currently assume, a fundamental deterministic evolution of our universe, but I also think that the term free will has a certain meaning compatible with that assumption.

It isn't necessarily a dilemma. It just depends on how the term is defined. Ie., one can assume a fundamental determinism (and there seems to be compelling evidence for this assumption), while still entertaining a connotation of the term free will that's compatible with that assumption. Ie., our choices and actions are causally linked to certain subsequent events.

One conception, phrasing, of free will is that you could have, given identical antecedent events, chosen/done otherwise. The problem with assuming this is that there's absolutely no evidence for it. All that's known is a certain set of antecedent conditions, a certain subsequent set of actions, and a certain subsequent set of conditions -- all of which is compatible with the assumption of a fundamental determinism.

Bottom line -- our universe doesn't appear, taking into account all observational evidence, to be evolving indeterministically. So, a fundamental determinism is assumed, which is compatible with a certain connotation of the term, free will.

sophiecentaur

People bandy around the term 'free will' but I doubt that anyone could genuinely quote an instance where they were aware of actually having made a purely mental decision (genuinely used their free will) and could describe how they got there. When you actually HAVE made a 'decision' then you start to rationalise it post hoc. On another day, you'd quite possibly come to the exact opposite decision. The term 'free will' is not unlike the term 'democracy'. In both cases the individual has some sort of mis-guided notion that they can actually affect what happens to them. We are at the mercy of Politicians, our pasts and our hormones (all 'random' and powerful influences on what we like to call our free choices.
The only decisions / conclusions that you can arrive at, ante hoc, are the conclusions that arrive from a mathematical process, which is repeatable again and again.
But Maths is neither like our brains nor the Physical World. It is based on axioms.
This thread can never go anywhere because people are trying to relate the nature of the Universe (deterministic or otherwise) to the detailed functioning of their brains (to a depth that has fundamental limits).

madness

I mean that in our universe, every identical physical setup will lead to an identical instantiation of consciousness. In philosophical jargon, this means that consciousness naturally supervenes on the physical. However, since it is conceivable that we could have lived in a universe in which these same physical processes lead to a different conscious experience (e.g. we see red as blue and blue as red), we see that consciousness and physical processes are not logically identical.

Ferris_bg

That sounds like the Zombie argument from Chalmers, but I don't like it and to be more precise, the word "conceive" in it.

madness

Well unfortunately, the arguments for physicalism (materialism) come from the same notion of supervenience, which is based on "possible worlds" or "conceivable worlds". It's not something you can get around if you are looking at philosophical debates of this kind.

pftest

About the supervenience: isnt that how all physical things work? If two riverbeds have an identical setup, the water will flow through them identically. If two planets are identical, the spacetime will be distorted identically. If two computers are identical, the current will flow through them identically. Etc. In all those instances, there is causal interaction between the system and that which supervenes (riverbed <> water, planet <> spacetime), and there is no epiphenomenon.

sophiecentaur

So how does this relate freedom to make a decision totally independently of the 'Physical' world? What do we mean by 'free will' (the most important word in the title of this thread)? If free will is just an illusion - a view that I tend to favour - then it is generated by the mind as a strategy for marshalling an incomprehensible amount of processes that are going on below the surface. These processes are subject to the same influences that are studied in Science but involve many more variables that are discussed in Physics. In the Physics of large numbers (gas laws and QM) the number of variables are much fewer than are involved in the functioning of the Mind and those situations are all dealt with statistically. In the study of the Mind, we have to use the same level of description that our consciousness uses, of course. This is, necessarily, very approximate and superficial - which is how I see a lot of 'Philosophy' working, being propped up by a set of axioms rather than data. Fair enough and very good fun - but is it really anything more?
This may be difficult for people to accept because it turns us more into automatons than perhaps we would like to be. But that explanation doesn't particularly have to interfere with enjoyment of life and appreciation of all the finer things. It just puts things into perspective.

madness

The point is to make the distinction between logical and natural supervenience, and to argue that consciousness supervenes naturally but not logically on physical processes. If something is logically reducible to physical processes, then it is in some sense reducible to or identical to those physical processes. If something is naturally supervenience then they are conceptually distinct entities which seem to coincide in our universe.

I think you may have misunderstood supervenience. Riverbed <> water is not an example of supervenience. H20 <> river is a better example, which would count as logical supervenience.

Pythagorean

Show me a river that's exactly identical to another river. Unique pattern generation isn't unique to humans.

It could also be that different physical processes can lead to (more or less) the same conscious experience. And in fact, they do at the molecular level. Changing concentration slightly in some local part of the brain would go unnoticed. In most cases, the systems would perform as normal. You already don't attend consciously to much of the plasticity occurring in your CNS right now.

Of course, taking half your brain out or something dramatic like that comes with consequences, but most people still "feel" like the same person, even though they may feel different about themselves. It's not like they lose complete memory of who they are.

http://en.wikipedia.org/wiki/Hemispherectomy#Results

Consciousness is an ill-defined problem. It depends on where you set all the ranges of the parameters of the set of observables that you consider to be consciousness. It's difficulty for us to intuitively understand high-dimensional objects.

It's obviously very difficult to measure subjective experience (which is where some people narrow their definition of consciousness to: the phenomenology), but people attempt other observable measurements.

http://en.wikipedia.org/wiki/Big_Fiv...onality_traits
http://en.wikipedia.org/wiki/Intelligence_quotient
http://en.wikipedia.org/wiki/Graduat...d_Examinations

In most social structures, many different members of society can fit the same role, where some social aspect of their personality is defined by the social vacuum they filled, not some internal emergent property.

madness

I'm not sure if you are trying to argue against what I have been saying because I don't particularly disagree with anything you wrote here. I don't really see how it fits in with what I have been saying. Supervenience doesn't imply a bijection between the base and supervenient properties it just implies that the supervenient properties are somehow entailed in the base properties.

Pythagorean

not at all meant to be a dispute; just another consideration.

Goodison_Lad

Good question. Is it possible to be conscious without thought? I think it is - we can be conscious of our thoughts, as we can be conscious of periods when there are no thoughts at all. This view would suggest that consciouness and thought processes are not the same thing, even though they occur in the same arena and usually together.

Very true. Should a computer pass the the Turing Test to everyone's satisfaction, there could be little doubt that what it was doing was functionally indistiguishable from thought. If this observable is taken to be a key indicator of consciousness, then the computer could reasonably be considered conscious. But I think many observables people suggest are more linked to thinking rather than the conscious experience.

The rather unsettling conclusion that must be accepted if you subscribe to the view that there is no such thing as genuine free will is that there can be no such thing as responsibility for your actions. If free will is an illusion, so is personal responsibility - your actions are the result of the laws of nature in operation, no matter how inscrutable the processes are. So, as an automaton, I cannot reasonably be held to account any more than I can put a computer on trial for some perceived misconduct. I may in practice be held to account - but it wouldn't be reasonable to expect me to have behaved any differently.

And a whole buch of other cherished notions would also be illusory e.g. merit. We already accept that it's silly, really, to praise somebody for how good-looking, tall, intelligent they are because they had nothing to do with it, yet we believe they had some control over their work-rate, generosity and so on.

Just because these are unpleasant conclusions doesn't mean they're not true. But I happen not believe in the existence of so many illusions.

Pythagorean

I don't agree. You're still accountable. And the other members of your organismal ensemble will make sure of it... in a deterministic matter.

sophiecentaur

It strikes me that the term 'supervenience', in this context, is just a way of implying a connection that is not necessarily there. Just because 'we make a decision' - which can obviously affect the way that the molecules of the World behave - does not imply anything at all about any 'supremacy' of that decision over the World. That decision can have easily arisen from the random arrangement of some of the atoms in our brains. Assigning any free action of the mind to make this decision and subsequent action is a massive assumption and not justifiable imho. The reason that you think you made a totally thought-out and independent decision need only be because your mind has developed to give you that impression. It is easy to see that some sort of evolutionary advantage could have turned us out in this way.