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The so-called Darwinian model of free will

  1. Oct 15, 2005 #1
    The so-called "Darwinian model" of free will

    See http://www.geocities.com/peterdjones/det_darwin.html#introduction

    The above link introduces the "Darwinian model", which purports to show how indeterminacy can endow an otherwise deterministic agent with free will.

    I prefer to call this model the Accidental model, rather than the Darwinian model (for reasons that will become clear later). With all due respect, I feel that calling it the Darwinian model is insulting to Darwin (imho I do not believe Charles Darwin would have wanted to be associated with this model).

    The main problem with most “indeterminacy” models of “free will” decision-making is that introducing indeterminacy arbitrarily into the decision-making process leads not to “free will”, but to capricious (irrational) behaviour. In the Accidental model, an attempt is made to remove the capriciousness without destroying the indeterminacy. This is done by having a 2-stage decision-making process. In the first stage a “random idea generator” (hereafter RIG) creates multiple alternate ideas according to an indeterministic process (this is the source of indeterminacy); in the second stage a “sensible idea selector” (hereafter SIS) examines the various alternate ideas created by the prior indeterministic stage, and rationally (and deterministically) selects one of the ideas for action.

    This model may seem superficially to provide a means of generating “free will”. There is a random element (the RIG) combined with a deterministic element (the SIS). The model is thus claimed to be both indeterministic and yet not capricious (it makes, up to a point, rational choices). But does it endow “free will”?

    Firstly we need to ask whether or not we have eliminated the capriciousness. If the RIG generates too FEW alternate ideas as input to the SIS, then the system will still appear to behave capriciously (the SIS will have insufficient choices for rational action because of the limited number of ideas generated by the RIG, hence overall behaviour will be dictated by the RIG). Therefore the RIG needs to generate a reasonable number of alternate ideas for each decision.

    Secondly we need to ask whether or not we have eliminated determinism. If the RIG generates too MANY alternatives as input to the SIS, then the system’s behaviour will start to be dominated by the SIS, which operates deterministically. Therefore the RIG needs to generate not too many alternate ideas for each decision.

    Can we say whether this model actually endows “free will”?

    I cannot answer that question definitively without making an assumption on the definition of “free will”, and that is a notoriously difficult thing to do (I do not agree that the definition provided in the above link is rigorous enough).

    In the absence of an agreed definition of free will, what I CAN do is both (1) to show how this model applies to “machines” and (2) to examine some of the strange consequences (which I have chosen to call flaws) of the Accidental model.

    1 – Applying the Accidental model to machines
    Imagine that we have a deterministic computer-based decision making machine (this should not be difficult, our present-day lives are surrounded by such machines, I am typing on one now).
    We now add to this machine a “random idea generator” which generates random ideas based on a truly indeterministic process (possibly powered by some quantum-based device). The RIG generates alternate ideas for action, inputs these ideas to the computer, and the computer then decides which of these ideas to turn into action. The computer in this case is performing the role of the SIS.
    Now, IF it is true that the Accidental model endows “free will”, THEN it also follows that the machine we have just created has “free will”.

    Would you agree that this simple machine has “free will”?

    If not, why not?

    2 – Flaws in the Accidental model
    Some may consider the implication that “free will” is endowed upon the simple machine described above a “flaw” in the Accidental model. I certainly do.
    Let us take a closer look at some other fundamental flaws in this model.
    Applying the Accidental model to a human subject, let us take a very simple “free will” decision process as an example, and work through exactly how the Accidental model is supposed to operate.
    The precise nature of the decision is not important, but let us assume that seen from a totally objective perspective the human agent has a total of 5 (and no more than 5) different alternate courses of action for this particular decision. We can label these 5 different courses of action as A, B, C, D and E.

    We need a benchmark against which to measure the Accidental model. Let us define the “Ideal Deterministic model” (ID model) as a world where ALL possible courses of action (and not just a selected number of the possible courses of action) are offered up to the SIS for consideration, and the SIS operates in the same manner as before, ie it selects the most rational course of action. The SIS is deterministic, therefore clearly each time we run the ID model we will get the same results from the same starting point. In each case, the ID model will select the most rational course of action from ALL possible courses of action (and not just a select few possible courses of action).

    Let us also suppose that we can “interrogate” the agent after each decision, to ask it questions relating to that decision. Now we take our simplistic scenario, where we have a total of 5 possible courses of action.

    Applying the ID model to our scenario, we find (let us say) that the SIS ranks these alternate courses in terms of rationality in the order E>D>C>B>A (where the SIS determines that E is the most rational course of action, and A the least). In this case, the model will always (deterministically) select E as the chosen course of action. Advocates of the Accidental model would clearly claim that the ID model does not exhibit any free will.
    (Note the actual number of possible courses of action is not important – it could be 5, 50, 500 or 5,000 – the logic stays the same.)

    Now let us take the same scenario, and apply the Accidental model. In this case, the RIG throws up a limited number of possible alternate solutions. Since there are a maximum of 5 possible solutions, the RIG clearly must throw up less than 5 possible solutions. Let us say that we run the model once and it throws up the 3 solutions C, D and E. The SIS works as before, and ranks these as before in the order E>D>C. In this case the agent chooses E as the course of action. When we interrogate the agent and ask it why it chose “E” as the best course of action, it will naturally say “well I considered three possible courses C, D and E, and E seemed the most rational course to me”. Nothing wrong with the logic there at all.

    Now run the Accidental model again, and we see that the RIG throws up a different combination of possible solutions, let us say A, B and C. Again the SIS ranks these in order of preference C>B>A, and the agent chooses C as the course of action. When we interrogate the agent this time and ask it why it chose “C” as the best course of action, it will probably say “well I considered three possible courses A, B and C, and C seemed the most rational course to me”. Again nothing wrong with that logic in isolation.

    If we now ask it “but in fact there is rationally an even better course of action, which is E. Why did you not choose E as a course of action” it will probably respond “ummmmm, oh well, I just never considered E as a possibility!”

    The question I have at this point is : Is this what we consider to be free will? To be able to choose a non-optimum solution simply because such a choice is non-deterministic (which is what the Accidental model boils down to)?

    We can run the Accidental model many times, and we will find that it does not behave predictably, since it chooses different courses of action depending upon the random output of the RIG. This is exactly what is supposed to happen, and advocates of this model will claim that it is precisely this type of indeterminism which endows the agent with free will.......

    Does anyone out there genuinely believe that this (the behaviour of the Accidental model) is what humans mean when they speak of human free will?

    The Accidental (or Darwinian) model clearly therefore does not endow free will, and I have yet to see an explanation of how indeterminacy in any form can endow an otherwise deterministic agent with anything that could be called free will....... does anyone know of a better model?

    MF
     
    Last edited: Oct 15, 2005
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  3. Oct 17, 2005 #2

    Q_Goest

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    You ask if indeterminacy can endow free will, but one could equally ask, can determinacy endow free will? Both questions make the assumption that we merely need to consider one or the other in order for the concept of free will to emerge.
    I'd have to say the basic assumption, that we merely need to look to the two possibilities of determinacy and indeterminacy, is incorrect. Basically, the question is flawed. Free will is a feature of consciousness. An unconscious mechanism has no free will regardless of whether it is made up of deterministic or indeterminate mechanisms. How consciousness comes about and why it should give rise to something called free will is unknown. A better question would be imho, "Can reductionism give rise to consciousness and can reductionism give rise to free will?"

    Edit: To elaborate, reductionism assumes all phenomena emerge from the interaction of causally deterministic and possibly indeterministic mechanisms or processes. One can break something up into small bits, larger than atoms or molecules but as small as or smaller than living cells, and the properties these bits have must produce all the phenomena we see. There is also the concept of emergence as defined by Laughlin and others which I understand to say that such properties as superconductivity, phase transition, superfluidity and other phenomena can not be calculated to emerge from the interaction of subatomic particles, but this is a slightly different type of emergence theory than the emergence of consciousness in a brain if and only if one proposes quantum phenomena have nothing to do with consciousness.

    Whether such emergent phenomena as proposed by Laughlin and others can give rise to consciousness requires there be quantum interactions in the brain. At least, that's the way I read his work. Feel free to point out any error there. The point is to clarify what emergent phenomena means. Emergent can mean the phenomena emerging from subatomic particles - but to suggest emergence of some phenomena depends on the properties of something as large as a neuron or even smaller is incorrect, I don't believe there is any such theory of emergence. If one can define something as large as a neuron that has no quantum mechanical interactions, then any phenomena which comes out of those interactions can be defined in reductionist terms. So without the process or mechanism of emergence being defined at this level, the question of determinate or indeterminate mechanisms giving rise to consciousness which can also give rise to "free will" is reduced to the question of "Can reductionism give rise to consciousness and can reductionism give rise to free will?" Thus the above question.

    In answering that, I think it seems obvious to most that the answer is yes, consciousness can come about from the interaction of neurons at a macroscopic leve, thus consciousness is governed by determinate physical interactions, and free will is governed only by determinate mechanisms. However, there is also a possibility that neurons interact on a quantum mechanical level, (a view held as highly as non-local hidden variable theories), in which case we have to go back to quantum indeterminacy to describe consciousness and thus free will depends on quantum indeterminate processes unless non-local hidden variable theories are real. So, "Can macroscopic reductionism give rise to consciousness and can macroscopic reductionism give rise to free will?" may be a more appropriate question.
     
    Last edited: Oct 17, 2005
  4. Oct 17, 2005 #3
    I'd say that the function of the decision making process and the manner in which it works would be the measure of free will.
    The example of possible decisions A, B, C, D, and E with E being the most logical course of action is too perfect. In reality there isn't likely to be any one course that is the very best.
    Consider a situation where there are multiple possible courses with approximately the same value in regards to being logically the best. The decision maker must decide what sort of outcome is preferable to it's self or situation even though say three of these outcomes are more or less equal in preferablility. Lets say that the decision maker does not "flip a coin" nor does the decision maker follow any explicit rules for making the decision, the decision making process will then likely lie somewhere between determinate and indeterminate wouldn't it? Would you say that this is about where the idea of free will fits in?
     
    Last edited: Oct 17, 2005
  5. Oct 18, 2005 #4
    Agreed that the source of free will (if it exists) may not lie “simply” in either deterministic or indeterministic processes – there may also be (as you describe) emergent phenomena at work.
    However, the statement “the world operates deterministically” must be (assuming the law of the excluded middle) either true or false. Hence the world is either deterministic or it is not. A world (or a system or a process) which is not deterministic is by definition indeterministic.
    Therefore if free will exists then “whatever process it is that endows free will” (whether or not that process is based on consciousness, whether or not that process is emergent) must be (overall) either a deterministic or an indeterministic process (there is no third way).

    I am not disputing that “free will may be based on emergent properties”. What I am saying is that (whatever the source of free will) it must be based on either a deterministic or an indeterministic process.

    How would you define free will? With respect, unless or until this definition is provided, OR we can provide an account of how consciousness endows some kind of free will, then the statement “Free will is a feature of consciousness” is (with respect) a statement of belief.

    Consciousness may indeed (as you suggest) be an emergent phenomenon (I prefer to use the term epiphenomenon, but you may disagree with some of the connotations of that term) of the brain. However it is not clear to me how such consciousness would then endow an agent with free will (where such free will does not exist in the absence of consciousness), and in the absence of descriptions of any of the properties of the free will thus endowed, it makes it difficult (even impossible) to provide any genuine understanding, or constructive critique, of the statement “free will is a feature of consciousness”.

    Can you give an example of another emergent phenomenon (apart from consciousness) that we could discuss in greater depth, to try to understand exactly what is going on in "emergence"?

    We need to be very careful with terminology here – by “indeterminate” do you mean the same as “indeterminable”, an epistemic property, or “indeterministic”, an ontic property. These are very different.

    Many Thanks

    MF
     
  6. Oct 18, 2005 #5
    I agree with this – but we may disagree on the details (see my preferred definition of free will below).
    Given a “deterministic sensible idea selector” (which is what is proposed in the Darwinian model), and given the same “input” each time, then it is necessarily the case that re-running the SIS will always “rank” the options in the same order each time. I agree it may be the case that the SIS may decide that two options are of “equal rank” (for example it may decide E=D>C>B>A), but the logic of my argument would still be essentially the same as before. If the SIS is then constrained to always pick “one” option, then in the case of E=D it would presumably just not be able to complete it’s task (unless we also provide a random selector stage after the SIS to cater for this possibility – but this would only make the final choice random and would not endow anything that could be called free will).
    “Approximately the same” is not synonymous with “exactly the same”. The SIS is deterministic, thus no matter how small the difference in value the SIS can (in principle) still discriminate.
    Again, “more or less equal” is not the same as “equal”.
    Is there something “between determinate and indeterminate”? What might that be?
    Take any given process, it is either determinisitic or it is not. If it is not deterministic then by definition it is indeterministic. Logically (it seems) there is no “third way”.
    Can you can explain what the properties of this third way might be?
    My oipinion? I think free will is compatible with both determinism and indeterminism (but importantly, being compatible with determinism, it does not REQUIRE indeterminism), but I probably don’t define free will the same way as most people who believe in what we might call “genuine free will”. I can offer my definition of free will, which is :
    Free will (definition) : Free will is the ability of an agent to behave rationally yet not necessarily predictably, where the source of the agent’s unpredictability is largely based on the complexity of the agent’s deterministic decision-making processes, and is not solely down to any indeterministic processes.
    In this definition I use the term “predictable” in the sense of an observer being able to predict the agent’s actions (ie predictability is an epistemic property).
    To my mind, the important issue is not so much “what is my definition of free will”, but more importantly “is my concept of free will compatible with either a deterministic or an indeterministic model of the universe?” (because there is no third way). If one’s chosen definition of “free will” is incompatible with both determinism and indeterminism then (with all due respect) one’s concept of free will is fundamentally flawed.
    with respect
    MF
     
  7. Oct 18, 2005 #6
    This is an important point in decision making though. Nothing in the real world, which humans whom supposedly possess freewill make decisions based off of, is perfectly quantifiable. This is why I say "approximately" and "more or less" because nothing will be "exactly" or "perfectly" equal. So you might say then that which ever has the "higher value" in such a case would receive the priority. If an outcome though is analyzed properly it will be analyzed in multiple fashions and in consideration to multiple attributes. In this way each outcome will have multiple values. Outcome 'E' could have a strong value under element 'x' but a weak value under element 'y' while outcome 'D' has a strong 'y' and weak 'x'. Then the value of each element to the outcome must be decided based on contexts and differing contexts could yield differing values for the elements. The value of the context must be determined. Evaluating a decision like this could easily go on for quite some time. The process has to finish at some point if it is to be useful. So either you have to set particular deterministic rules that will make the process choose one over the other or set in a "flip of the coin" function to make the decision randomly. Which would best parallel a human's decision making though? And if the final decision is based on the "flip of a coin" function is it then a deterministic or non-deterministic process(assuming that the coin flip is truely random)?

    Sorry. This is the product of my preferance to stray from binary thinking. I don't like to consider things to be only one way or another because in my experience things never seem to turn out simply one way or another. Perhaps some things are deterministic while others aren't or perhaps everything really is deterministic but due to a lack of ability to measure and quantify certain elements of reality they are non-deterministic in a pragmatic sense.
     
  8. Oct 19, 2005 #7
    Agreed. The decision-making in the Darwinian model is carried out by the SIS, which is purely deterministic. No matter how complex the decision-making algorithm, no matter how many variables or how many “multiple fashions” or “multiple attributes” are involved, the SIS will carry out this process relentlessly deterministically, such that re-running it with the same input, no matter how complex the decision-making algorithm, will always produce the same output (that is the definition of deterministic). That output may indeed include an “equal ranking” of some possible options, but this does not detract from the argument or change the conclusion that “there is nothing involved in the decision-making which could reasonably be called free will”.
    The SIS is purely deterministic, hence (if it is able to identify an option with a maximum value) it will always behave deterministically, there is clearly no free will here.
    If you are however suggesting that another “stage” be added to the model, subsequent to the SIS, which involves a truly indeterministic choice between two equivalent choices by the SIS (in the case where for example the SIS decides that choices E and D have equal value), then this would be the equivalent of the “flip of a quantum coin”, and would result in an indeterministic outcome. But are you suggesting this indeterministic coin-flip is the source of free will?
    I am not saying the world is black and white in the sense “everything is deterministic” or “everything is indeterministic”. What I am saying is that each “thing”, each component of our universe, must be either deterministic or indeterministic.
    Are you suggesting here that you believe there exist some things/processes which are genuinely neither deterministic nor indeterministic? Can you rationalise and defend this, or is it just (with the utmost respect) hand-waving?
    MF
     
  9. Oct 19, 2005 #8
    .

    Ye-e-es If you fiddle with the parameters it will stop working.A kidney or heart will stop working under
    the wrong circumstances too. The point is
    that there is at least one way in which it could work.


    "Why not" has to have something to do with the definition of FW being
    employed. If it is the ability to make unpredictable choices, then yes it
    does. If it is that ability combined with certain levels of consciousness
    and rationality, then no, it doesn't. If you think artificial intelligence is
    possible, then yo need to explain why FW would not be included along with
    other human faculties. If you think AI is impossible you need to explain
    why -- are people equipped with non-physical souls ?

    It is also the ability to generate better, more optimal solutions in the first
    place. You speak as though your solutions A..E are hardwired givens. But they
    have
    to come from somewhere. If not from some kind of trial-and-error (even over
    evolutionary time), then where ? A faculty that could generate
    the optimal solution in any given situation would indeed be more worth
    having than FW as I describe it, but I do not see how such a faculty could
    exist naturalistically -- it would be a kind of omniscience. The first time
    someone's RIG ever comes up with a particular idea is IMO the creative process itself.
    It is true that everybody before that was behaving sub-optimally in relation
    to it. But your
    only alternative would be to be born as gods, knowing everything.
     
  10. Oct 19, 2005 #9
    It think I used the pharse "more or less deterministic". A SIS which
    operated on a fixed set of rules would not be much good, as there
    would be no capacity to learn form experience. OF course learning
    ability need not be partiuclarly indeterminstic.
     
  11. Oct 19, 2005 #10
    "more or less deterministic"?????

    That sounds like a good escape route :smile:

    We are left with the same puzzle. If the SIS is not entirely deterministic, then in what sense can the inclusion of indeterminism in the SIS "endow free will"?

    It's like trying to grab hold of a slippery snake, which has lots of escape routes to evade capture :smile:

    I disagree. I can see how a completely deterministic machine could learn from experience. I don’t see what “learning” has to do with indeterminism.

    Exactly right. In fact, why need learning ability be indeterministic at all? If I am going to learn from experience I am sure that I would want that learning to be rational (deterministic) and not random (indeterministic).

    MF
     
  12. Oct 19, 2005 #11
    Sorry, I’m not sure what is being objected to here. I am not suggesting “fiddling with the parameters”, I am just looking to see what properties the RIG must have in order for it to be effective. One property is that, in order to be effective, it must offer up less than 100% of all possible actions (otherwise the entire model becomes deterministic), but at the same time must offer up a reasonable percentage of all possible actions (otherwise the entire model becomes capricious).
    Surely whether it “works” or not is demonstrated by whether it endows something that could be called free will? Which I respectfully suggest has not yet been shown.
    Is this what you mean by free will? Simply the ability to make unpredictable choices? Surely not. Any random number generator can do that.
    What would the inclusion of consciousness and rationality add to the model (in terms of endowing free will)? Surely nothing could be more rational than the SIS, which is already included?
    Implicit in this is the assumption that free will (however we define it) exists. The assumption may be wrong.
    Sorry, I do not understand the question. I need “to explain why….. what”? “Why are people equipped with non-physical souls?” I am not suggesting they are.
    You have a very valid point here, and it may indeed be the case that there is something akin to the RIG in the human brain (I never suggested this could not be the case). The RIG would then serve the purpose of generating random ideas which we can analyse rationally. This may be where “intuition” comes from (or may be an element of intuition).
    In order to generate apparently random ideas, must the RIG necessarily be indeterministic in this case? I would suggest that an indeterminable RIG would serve the purpose (of generating apparently random ideas) just as well. A computer random number generator is deterministic yet not determinable (unless one knows the algorithm).
    The problem is, I do not see how this alone (whether the RIG is truly indeterministic or just indeterminable) can generate something that we call “free will”. Again I would cite the example of the simple deterministic machine, with a RIG tacked onto the front of it. The machine output may no longer be determinable, but in what sense are you suggesting that it then has free will?
    MF
     
  13. Oct 19, 2005 #12

    Q_Goest

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    Ok MF, I don't know if this will help at all or not, but I'll throw it out there for consideration. Consider it "just a thought".

    Regarding free will - is this a feature of consciousness in the sense that a conscious entity experiences a sensation that the future has yet to be determined? Or is free will a mechanism that can be reduced to deterministic and indeterministic processes? The first definition seems more reasonable to me, free will seems to be something we experience. People seem to know what free will is but it's rather difficult to define except in terms of how it feels to have it or experience it. Free will is the experience that we are making choices. It is not the process of making that choice. So to answer the question, "Does free will require indeterminate processes" seems to be the wrong question, I define it as a feature of consciousness. I think it's incorrect to try to define it in terms of determinism and indeterminism. It is not a process, it is an experience of making a choice just as the color red is not a process it is something we experience when we see a particular color.

    One could come back and ask then a more pointed question, "Does making a decision require indeterminate processes?" I think this is a bit more to the point of your question. It's still not very good because it still makes some assumptions about what may or may not be happening. The only indeterminate processes we know of are QM processes, and as you've pointed out it may be incorrect to ask the question if these processes are determinate or not. One could suggest non-local hidden variable theorems can explain determinate processes so the universe is determinate. But such a process may (or may not) be beyond our ability even in principal to know. (is that ontic or epistemic? Please explain, I'm not up on all the philosophical terms yet.)

    I think the better question to ask is the one I've suggested earlier, and one that helps reduce the question to the possibility that QM processes may be relied upon by the brain in order to give rise to consciousness.

    How would you answer the question, "Can macroscopic reductionism give rise to consciousness and can macroscopic reductionism give rise to free will?"

    If you say "Yes, macroscopic reductionism is sufficient," then the answer to the question, "Does free will require determinate or indeterminate processes?" the answer is "determinate processes". Would you agree to that? I don't know there are any other good responses. If we assume consciousness is computational or if we assume more broadly that it relies on laws of physics at a macroscopic level then there really doesn't seem to be an alternative response. Can you think of any logical way one could respond, "Yes, macroscopic reductionism is sufficient but it depends on indeterminate processes."? For example, one might suggest the flip of a theoretical "GhostCoin" is indeterminate (whatever that is), and thus can get us away from having to concede that consciousness is dependant on determinate processes. But I think once we get above the level of quantum uncertainty, things such as die rolls, coil flips and random number generators in computers are all determinate and I think you'd agree with that.

    So if one can prove computationalism is false, if one can create a working theory which includes a test that can be used to prove that a given phenomenon is not reducible to its constituent parts (at a macroscopic level), then what we have proven is that consciousness depends on something other than what I'm referring to here as "macroscopic reductionism". It must depend on quantum mechanics.

    That said - please note that this of course assumes no "emergent" phenomena can come out of such a system which arises from a "macroscopic reduction" of the system. If (a BIG if) we assume such emergent properties exist then we need to come up with a theory about those emergent properties which is something that's never been done before nor even seriously considered. Emergent properties are only seriously considered at the QM level as far as I know. So I'll dismiss emergence as a possible way out of the conundrum if macroscopic reductionism is insufficient.
     
  14. Oct 20, 2005 #13
    Imho I believe so, yes. (Caveat : The “danger” of expressing free will simply in this way is that it then “seems like an illusion” – which with all due respect I think does a dis-service to the concept of free will. I believe free will is alive and kicking, it just needs to be defined very carefully, and it is probably not what most people like to think it is).
    Imho, by definition any given mechanism msut be (overall) either deterministic or indeterministic – if this is not the case, what could the “third way” be?
    Agreed (with the caveat given above)
    This is good. I like it. But I wonder if this definition of free will (that free will is just a feeling, like the sensation of seeing the colour red) would be acceptable to those who profess to “believe in” the everyday concept of free will? It would be interesting to know Tournesol’s opinion on this?
    This is not the question I was trying to address, but let’s go with this for the time being.
    Epistemic is what we “know”. Ontic is what “is”.
    The core philosophy of classical physics is based on the premise that we can in principle “know” what “is”. The quantum revolution buried that idea for good (there is a fundamental limit, what I like to call the epistemic horizon, to what we can ever “know” about “reality”).
    Do you mean "Can (macroscopic) reductionism explain consciousness”?
    Before I can attempt to answer that question, I would first have to ask “what exactly is it that we are trying to explain?”. We could explore this, but it may take us a long way off-topic – perhaps we should start another thread for this question?
    On the second question “can (macroscopic) reductionism explain free will?", I would first have to ask “what do you mean by free will?” The definition of free will I have offered above (see post #5 of this thread) is :
    Free will (definition) : Free will is the ability of an agent to behave rationally yet not necessarily predictably, where the source of the agent’s unpredictability is largely based on the complexity of the agent’s deterministic decision-making processes, and is not solely down to any indeterministic processes.
    In this definition I use the term “predictable” in the sense of an observer being able to predict the agent’s actions (ie predictability is an epistemic property).

    I believe that free will as I have defined above is completely understandable in terms of reductionist principles.

    No. I don’t see that reductionism is necessarily linked to determinism (in the sense that “deterministic processes” implies “reductionism”). This would imply that reductionsim is incompatible with indetermnism, and I don’t see why that should be the case?
    Reductionism has nothing necessarily to do with determinism.
    But then, with respect, I personally do not believe that the introduction of indeterminism helps us to explain anything, so there is no point asking me whether there is any meaning to the statement “macroscopic reductionism is sufficient but it depends on indeterminate processes”.
    Yes. I see no “benefit” that any kind of ontic indeterminism endows on the world – it does not explain concepts like free will or consciousness.
    OK. Can you provide an example of a phenomenon that is not reducible to its constituent parts?

    MF
     
  15. Oct 20, 2005 #14

    Q_Goest

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    How do you know if something is reducible to its parts without a theory of how to do that? How do you reduce something to its parts and then determine if a phenomenon can exist or not? Is there a theory and a test of some sort one can utilize that can logically and mathematically reduce a given mechnism to its constituent parts, and then provide a test with which you can determine if the phenomenon is still possible or not?

    With this theory and test in hand we can go around and reduce phenomena and test all sorts of things! Unity and the binding problem would be the first target.
     
  16. Oct 20, 2005 #15
    You have defined FW as the ability to make rational choices that are
    unpredictable. If D and E are both rational, and you choose randomly between
    them (the Buridan mechanism), that seems to fulfill your criteria.

    (However the real problem is that you are assuming that because the SIS is
    more-or-less deterministic, it always makes the same choices given the same
    inputs -- although deterministic systems can adjust their weightings on the
    basis of feedback).


    If a process is deterministic, B will follow on A 100% of the time. If it is
    not, it will be less than 100%. Less than 100% could be 99.9%; it could be
    0.01%. It seems to me that it is mostly middle ground.


    Meaning that you can no longer say "Fred has FW" but rather "Fred has FW as
    judged by John, but not as judged by Mary, who has access to a supercomputer
    loaded with information about human psychology".

    If one has good reaon to suppose that FW exists in the first place. Some
    people claim that there is good reason to define FW in a way that is
    incompatible with both determism and indeterminism, and conclude
    that FW does not exist.
     
  17. Oct 20, 2005 #16

    Q_Goest

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    Yes, I don't think I've made the point very clear. The point is not that indeterminism is incompatible with reductionism. I accept your argument that one might in theory be able to reduce any mechanism to its constituent parts and those parts may be indeterminate, and reductionism can include both determinate and indeterminate processes.

    The point is that we all seem to recognize such things as the roll of a die or the toss of a coin are determinate, and we intuitively understand this because such objects are relatively large and not affected by quantum uncertainty. The question regarding free will depends on what assumptions we make about consciousness. If we assume consciousness can be created by macroscopic things like switches then free will depends only on determinate mechanisms. If we assume consciousness depends on quantum mechanical things, then free ill may (or may not) depend on mechanisms that are indeterminate. So the question, is free will endowed by interdeterminate mechanisms has everything to do with our assumptions about what physical processes are needed for consciousness.

    I realize this isn't an answer to your question nor is it likely to feel like a good answer to you because it doesn't address your desire to understand what possible processes are used by a conscious entity to endow free will. But if we assume free will is a feature of consciousness, a feeling or experience, then the assumptions we make as to how consciousness can come about (ie: computationalism versus some QM mechanisms) directly affects our conclusions regarding free will.
     
  18. Oct 21, 2005 #17
  19. Oct 21, 2005 #18

    Q_Goest

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    Tournsel, yes I can accept the point that perhaps chaotic behavior can in fact be due to 'quantum indeterminism' if we look hard enough (is that your point?)

    However, computer switches (or "symbol manipulation") are completely determinate processes. There is unfortunately no room there for indeterminate behavior by a computer except perhaps for us to suggest:
    1. QM results in the computer "breaking" (ex: stress fractures within the chip might be at least be due to bonding energy and when the bond breaks and results in catastrophic failure might be very very slightly affected by indeterminate QM processes.).
    2. A computer switch governed by radioactive decay. :yuck:
    3. etc... (processes that break the machine or otherwise are not simply computational) (Double yuck!) lol

    But a computer that hasn't failed nor is it connected to some other QM mechanism is completely deterministic.
     
  20. Oct 21, 2005 #19
  21. Oct 21, 2005 #20
    With respect, there is no conclusive evidence that QM is necessarily ontically indeterministic. The results of QM can be explained in terms of deterministic non-local hidden variables.
    Perhaps.
    Not necessarily. Even though free will may be a feature of consciousness, it may not necessarily depend very much on how consciousness comes about.
    MF
     
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