Date: Thu, 10 Sep 1998 22:00:07 -0700 From: Stuart Hameroff Subject: [q-mind] Free will - Henry Stapp and David Hodgson MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" >From Henry Stapp To: David Hodgson Subject: Re: free will Dear David, Glad to know that you're e-mail accessible. I thank you for your delineation of our similarities and differences. Let me see if I can narrow the gap: I'll do so by interleafing some comments into your letter. On Wed, 9 Sep 1998, David Hodgson wrote: > Dear Henry, > > Thank you very much for your letter of 31 August, the e-forum material, and > your paper. I agree with very much of what you say, but we still diverge > at a few crucial points. > > Yes, our sophisticated theories are basically about 'close together and far > apart' and 'pushes and pulls' - but I think they're also about 'relevantly > like' and 'relevantly unlike', and that they depend upon qualitative > judgements and not just quantitative computations or proofs, and indeed are > ultimately resistant to any kind of mathematical or conclusive proof. My current position is that reality is basically knowledge-like: it is a growing state of (universal) knowledge that has a lot of mathematically representable structure. Our best contemporary way of representing this mathematical structure is via the quantum theoretical formalism, which combines the math of the deterministic (Schroedinger) evolution with the math of random variables. But there is a slackness described in my Whitehead paper, and the relationship of mathematics to this slackness is unknown.. > Our > brains could indeed be doing all they do by a basically mechanistic > process; but I suggest that if so, we cannot be rationally justified in > believing this, with any assurance. True. All we really know, with any solid basis, is that this formalism: (1) works very well in the very few cases where we can really test it with high precision, and (2) seems compatible with all the "solid" evidence. [I put in "solid" as a caveat, because of the putative paranormal "evidence", which I do not discuss here]. But the validity of EXTRAPOLATION from the well controlled physical cases to a system as complex systems as human mind/brains is a theoretical assumption, not a logical necessity. Still, science ought to push as far as they can the simplest logically coherent theory compatible with all the empirical evidence. > > I agree it is not enough to say that choice is fixed neither by laws nor > chance (nor both); and I acknowledge this in my section on plausible > reasoning. I think the explanation of our choices has to be sought > essentially through deep and careful consideration of the nature of our > informal rationality, including our moral and prudential reasoning. My Whitehead paper seems to establish that a person's conscious thoughts, per se, can enter into the determination of the course of his thinking in a way that shift some part of the causal chain outside the body/brain route that quantum theory specifies mathematically. This result lends support, coming from within the framework of contemporary physical theory. to your thesis of a possible non-mathematical component. > > Turning to your Whitehead paper, it seems to me that the observer's freedom > to choose what question to pose cannot, on your approach, be 'unconstrained > by known laws of nature' and not 'compromised by the statistical element in > quantum theory' as you suggest on p2. > > Assuming the choice of question involves experience, don't you have to say > it is the result of rules, chance, and perhaps a prior choice of question - > and so on back to the earliest relevant choice of question? You seem to > concede this in your communication of 31 August when you say 'the otherwise > completely loose Heisenberg choice ... is controlled by the experiential > quality felt as "direction of attention" in earlier experiences.' You > later say that 'the issue of which possible experience e will be placed in > the question "Will e occur or not?" is not specified by the ordinary rules > of quantum theory'; but later again you seem to say that 'the influence of > intentionality of the present thought on the choice of the next question > .. is pretty mechanical because it follows from the quantum equations.' > My point seems to have been lost. I am not denying causation. The question is the structure of this causation. I am suggesting that the flow of conscious experience is not wholly determined by the local determinist law (expressed by the Schroedinger equation) in conjunction with the random choices, but that the causal chain goes through experiences in a way that makes the causal process not fully reducible to the laws of contemporary physics, and hence, as far as we now know, perhaps not fully reducible to mathematics at all. A coherent understanding of this is provided by taking the experiential increments in knowledge to be the realities. They are merely REPRESENTED (provisionally and pragmatically) within the physicist's representation of reality, namely the quantum state S of the universe, as a reduction of S that picks out, as a wholistic unit, from the prior potentialities, the entire pattern of brain activity that represents that experience. But the real process is in mind, and this process has a causal structure that is only PARTIALLY represented within the mathematical structure provided by contemporary physical theory. > The other (closely related) area where we diverge is your assertion that > 'the basic realities [are] idea-like events that are connected to each > other by the mathematical rules' - and your associated assumption that > 'each of the possible experiences e, being a possible real thing that can > actually occur in nature, will have a mathematical description and be a > possible mathematical object'. > > I'm not sure why you feel able to assume anything real must have a > mathematical description. I think experiences (such as of colour and pain) > have qualities that cannot be completely captured by any mathematical > description - and also that experiences in fact involve the interdependent > existence of conscious subject and object (experiencer and experience, or > doer and thing done), and that subjects cannot be completely captured by a > mathematical description. > > Such mathematical description as can be given of the subject and object (or > subject-and-object) may determine statistics for experiences and actions - > but I think that there will be a 'qualitative' residue, undescribed by the > mathematics, that will have a role in choices between possible outcomes, > choices that ultimately can be explained only in terms of the inconclusive > plausible reasons on which our decisions and actions appear to be based. > > Kind regards, David > > You are correct. What I should say, and indeed did say above, before I came to these final remarks of yours, is that the reality, which is growing knowledge, according to the pragmatic-idealist account, has a structure that is only partially described by contemporary quantum mechanical theory: my Whiteheadian-paper analysis show that something is left out. Whether or not this left out part can be expressed in "mathematical terms" or "logical" terms is an open question. In fact, what "mathematical" means in this context becomes problematic. Since this part is: (1) not fixed by the Schroedinger equation in conjunction with the random choice, and hence is not fixed by the math that physicists would normally say are controlling the physical aspects of nature, yet (2) seems to be tied to whole "thoughts" or "feelings", it seems clear that more evidence and theoretical development is needed to determine whether we can find any useful description of this extra left-out part beyond the detailed descriptions of our thoughts as they actually appear to us. So I guess it all boils down to saying that the development in my Whiteheadian paper brings me into a position of now being able to agree with your essential point, that we have no rational basis for saying that our experiential processes are completely governed by mathematically describable processes, or, in particular, by the sort of theory that physicists use to describe physical reality. I must add, however, that quantum theory does seem to specify a very narrow window for these effects. This means that scientists can study these effects within largely adequate quantum theory, much as they studied quantum effects within largely adequate classical theory. In that earlier case scientists discovered, within a structure that seemed irrational, a more complex mathematical structure that allowed the former theory to be recovered as a limiting case of its successor. Best wishes, Henry P.S. I think this exchange will be of interest to the e-forum q-Mind, and the Klein-mini-forum, and would like to post it. Do you object? Date: Thu, 10 Sep 1998 20:46:17 +1000 From: David Hodgson Dear Henry, I have no objection to your posting our exchange as you think appropriate. I'll respond in more detail in due course. Regards, David From stapp@thsrv.lbl.gov Wed Mar 3 10:37:04 1999 Date: Tue, 2 Mar 1999 12:15:00 -0800 (PST) From: Henry Stapp To: Hodgson Subject: Re: Your article On Mon, 1 Mar 1999, Hodgson wrote: > Dear Henry > > Thank you for you article 'Attention, intention and will in quantum > physics'. I very much agree with most of it, apart from your disavowal of > any reliance on randomness (pp5-6) and your sharp distinction between Dirac > choices and Heisenberg choices. > > At p15 you say 'The Heisenberg Choice ... is not fixed by the Schrodinger > equation, or by the Dirac Choice ...' I think this leaves you open to an > infinite regress objection. The Heisenberg Choice must arise from the > previous development over time of the system, and thus from the Schrodinger > equation and a Dirac Choice and a prior Heisenberg Choice; and the same > will apply to the prior Heisenberg Choice; and so on. You never get to a > Heisenberg Choice that injects indeterminism otherwise than by randomness > plus a prior Heisenberg Choice. You misunderstand me. I am not trying to get indeterminism. I am espousing a deterministic universe in which there are three intertwined processes, 1, the Schroedinger micro-local process, 2, the Heisenberg process that is explicitly in terms of thoughts, per se, and is represented within the quantum formalism in terms of properties of reduction events that project onto the neural correlates of conscious experiences, and, 3, a Dirac process that is global in nature, but because of our ignorance of the relevant global variable we must represent statisically. > > I believe the way to avoid this regress is to adopt my position which, as > you know, is that human choices (or intention or attention) determine > outcomes that the physical viewpoint can only treat as random. I know you > disagreed with my original formulation of this, but I think its current > formulation in the section on randomness and choice in my paper 'Hume's > mistake' (current version enclosed) shows that this can be embraced without > any conflict with quantum physics as a physical theory. > As far as I have determined we are in agreement, and differ only in that I am giving a description that is, from a physicist's viewpoint, more detailed, and more particularly identifies the lacuna in the quantum theoretical description that allows our thoughts per se to enter into the dynamics in a real bona fide way that is not parasitic upon the Dirac choice, which quantum theory claims to be purely random, and hence not baised by our thoughts: I allow the pure randomness of the Dirac choice to be strictly maintained, and the local determinism of the Schroedinger process to be strictly maintained, and yet find a causally efficacious real role for thoughts per se. > To me it is a pity that you burn your bridges as it were by so totally > denying relevance to the (apparent) randomness of quantum physics and thus > (so it seems to me) leave no room for escape from the regress objection; > particularly when we are so much in agreement on everything else. > As I say, I believe that there is within quantum theory room for our thoughts per se to act efficaciously to block the infinite regress by resolving at each stage the Heisenberg choice. Of course, in a fundamentally deterministic universe there are always causes, and in that sense a possibility of tracing backward to prior causes. But I see the problem not in the fact that everything has some sort of cause, but in the notion that this cause must be either of a local-mechanical or ramdom kind. The alternative in which complex real entities, our thoughts, enter directly as such into the causal chain is what is needed. I show how quantum theory, rationally developed, has an actual need for the entry of such a real element in the causal structure, even without appealing to the vagaries of the Dirac Choice. I would very much appreciate receiving a hard copy of Hume's Mistake. Best regards, Henry From stapp@thsrv.lbl.gov Wed Mar 10 13:05:07 1999 Date: Wed, 10 Mar 1999 13:03:29 -0800 (PST) From: Henry Stapp To: Hodgson Subject: Re: Your article Dear David, Many thanks for your patience in trying to allow me to understand the distinction you are driving at. It is a very difficult one for me to grasp. Perhaps there is just no hope for me, and we should give up on it. But your more detailed definitions certainly help to make the problem clearer. Let me comment on your endeavour in the light of these very helpful additions. On Wed, 10 Mar 1999, Hodgson wrote: > Dear Henry, > > When I say pre-determined or fixed in advance, I mean just that the initial > conditions and LAWS determine or fix a unique outcome before it occurs, > whether or not this outcome could be described in advance or calculated in > advance. > The word "laws" is not defined. I proposed that if, for any given the initial conditions, one and only one course of events is possible that then whatever constraints pick out, given the initial conditions, the unique course of events be called the "laws". > When I say an outcome is not pre-determined, but comes to be determined or > fixed by its antecedents when it occurs and no sooner, I mean literally > that the initial conditions and laws do not determine or fix the outcome > before it occurs (NOT just that the outcome cannot be described or > calculated in advance), but that the antecedents may nevertheless cause a > unique outcome, and thus determine it when it occurs, in bringing it about > by choice and not just by the operation of laws. (No generally applicable > law can be specified before or after the event linking initial conditions > and the unique outcome.) > With my definition of "laws" if the course of events is fixed, given the initial conditions, then it is the laws that do the fixing. Hence the whole issue becomes focused whether an event that is fixed by the laws is fixed "before" the event occurs or "when" the event occurs. In the most familiar case, namely a motion that is fixed by a differential equation, I think it is fair to say that the instantaneous value at time T is fixed at no time T' that satisfies T'< T. Thus, in your terminology, the value is not determined before the event, but only by a "choice" made at the time of the event. [Of course, you say "by a choice and not by the operation of laws". But with my definition of "laws" if what happens, given fixed initial conditions, can be only one thing then it is the laws (the operation of the laws) that do the fixing. So it is a contradiction in terms to say that a value is determined "by a choice and not just by the operation of laws".] It seems to me that, in spite of your commitment to rationality, to which you generally adhere so admirably, some murkiness has crept in here, right at the critical point. > The difference I am trying to bring out is between a process which is no > more than the working out of initial conditions and laws, so that > everything is fixed in advance whether calculable or not; and a process > which causes a unique outcome by resolving what was previously > inconclusive, such resolution becoming complete and definitive no sooner > than the actual occurrence of the outcome. > But no causal process actually, as a real process in time, fixes things in advance: causal processes fix things instant-by-instant as time advances. This distinction that you want to make between "laws" and "choice", and between "in advance" and "no sooner than" may have some roots in our intuitions, but the problem is how to reconcile those intuitions with rational analysis. It seems to me that Hume got it right, or at least that Hume followed a rational line of argument that I can follow. > There is force in your objection to separating the causal process into two > parts, when it is reasonable to believe in just one ongoing process. It is not, I think, just a matter of "reasonable to believe". It is a matter of making clear logical distinctions, and then arguments that follow rationally from them. > But I > say we don't at present have concepts adequate for a unitary account of the > single process, In Hume's day there was the clear idea of local deterministic Newtonian mechanics. Today we must accept nonlocality. So we can assume a non-local deterministic dynamics.. > and that the best we can do is to use the two incomplete > accounts we have, one in terms of the rules-and-randomness of physical > causation and one in terms of the choices of mental causation. At the > present, the best account of causation requires both - rather like the best > account of matter at present requires both the wave and the particle > versions. > On what grounds, other than your wish to adhere to ancient tradition and inherent intuition, do you assert that this is "the best we can do". Are you not open to the charge that you are, in the end, just accepting your own prejudices? I, for one, think that we can do far better than merely accept our own personal prejudices, and that doing better than that is what this sort of inquiry ought to be doing. > I think I previously sent you an early draft of my new book on choice, on > Ch3 of which 'Hume's mistake' was based. If you would like to see the > current version, I could send it to you by email or in hard copy. > I have been asked by Univ, of Arizona Press to review your new book, and have just received from them a copy. I admire your work, and expect to be able to give, after reading it, a favorable review. But I shall probably also need to express my reservations about this particular point that we are discussing, since it is pretty crucial. So any help you can give me to better understand your position would be helpful to me in my task. > The regress I complain about won't worry you if you are happy with > out-and-out determinism. But I am looking for a choice which is not itself > pre-determined by its antecedents, and so a regress to prior choices would > concern me. > I find out-and-out determinism (highly non-local of course) to be the most understandable possibility. I believe that, given a reasonable nonlocal determinism, the normal statistical rules of quantum theory can be DERIVED from it, as a consequences of our lack of knowledge about far-away aspects of the universe, and that our thoughts per se can enter in a causally efficacious and irreducible way into brain dynamics. I think this deterministic model provides a rational way of understanding ourselves that is compatible with our intuitive idea of ourselves, and the role of our minds in the determination of our actions. It does justify your general position, but in a way that I find clear and rational.. I suddenly recall, just now, about my distinction between Process Time and Physical Time (formerly called Einstein Time), and my picture of world process: Process Time ^ | -------- | | | | | -------- | | | | |----- | ------------------------------------------> Physical Time The horizontal evolutions are via the normal unitary evolution, and Physical Time is time in the rest frame of the universe. The vertical segments represent quantum jumps: instantaneous changes in the state of the universe. Something must fix, in a quantum jump, what the new state will be. But this something is not normal unitary evolution. This "Choice Process", which determines what the state will be after the jump, is represented by the vertical segment. Each such segment is confined to a single Physical Time, but has a finite extension in Process Time. This distinction between Process Time and Physical Time is explicit in the so-called "Heisenberg picture". In that representation the normal unitary evolution is attached to the `operators', not to the state, and it extends uniformly over all spacetime. It is frame independent (relativistically invariant). The quantum jumps are a completely different sort of beast, The state changes, rather than the operators, and this global change is instantaneous, in physical time.. This picture gives me a way of understanding what you are trying to get at. The key point is that limiting value/form of the state from times before the jump differs finitely from the limit from times after the jump: a finite change has occurred in zero physical time. This finite change involves, according to orthodox QM, TWO choices, the "Heisenberg" Choice of which question is to be put to nature (This choice is made by the experimenters), and the "Dirac" choice of what the answer will be. (This is sometimes called Nature's Choice) So NOW I can understand you: what was missing from your earlier account was the idea of a finite change occurring in zero physical time. Hume was thinking in classical (Newtonian) terms, where there were no instantaneous finite changes. In that context the idea of breaking the process in two is artificial. But if there is one process that occurs in physical time and another that occurs over a finite duration yet is confined to an instant in physical time, then the situation is quite different. Best regards, Henry