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Henry StappIntroduction and articles relative to Henry Stapp's theory of quantum consciousness 1.) Introduction 2.) Attention, intention and will in quantum physics - Henry Stapp 3.) Bourget's criticism of Stapp 4.) Reply to Bourget's critique - Henry Stapp 5. The Hard Problem: Henry Stapp Introduction: Henry Stapp Henry Stapp believes that classical physics cannot describe the brain, and thinks that a quantum framework is needed for a full explanation. He is sympathetic to the pre-quantum age ideas of William James, who suggested that consciousness was a ‘selecting agent’ present when choices have to be made. Stapp bases his theory of consciousness on Heisenberg’s interpretation of quantum theory. The Copenhagen interpretation was the first quantum orthodoxy promulgated by Neils Bohr. This was pragmatic in recommending quantum mechanics as a system of rules that allowed the calculation of empirically verifiable relationships between observations. Heisenberg refined this position. Bohr and Heisenberg agreed in viewing the theory as a set of rules for making predictions about observations made under experimental conditions. However, Heisenberg thought that the theory was something more than a system of statistical rules, and that the probability distribution of quantum theory really existed in nature. He considered that the evolution of this probability distribution was punctuated by uncontrolled quantum wave collapses, which are the events that actually occur in nature, and the manifestation of which eliminates the other possibilities in the probability distribution. The emphasis is thus on the probability distribution. Heisenberg did not view the quanta as actual things, but as tendencies for certain types of events to occur. The orderly evolution of the quantum system is deterministic, but this controls only the tendency for things or propensity for events and not the actual things or events themselves. The things or events are controlled by quantum jumps that do not individually conform to any natural law, but collectively conform to statistical rules. With respect to the brain and consciousness, Stapp considers that some brain processes such as the calcium ions that are involved in the release of neurotransmitters at synapses need to be treated quantum mechanically. Further, he thinks that the non-linearity of the synaptic system and the large number of metastable states into which the brain can evolve point to a quantum mechanical structure. Top-Level Control Although Stapp thinks there is quantum based activity in the synapses and possibly other aspects of the brain, his theory, in contrast to quantum brain dynamics or Orch OR, is not really based at the microscopic level. Instead, Stapp envisages consciousness as exercising top-level control over neural excitation in the brain. Quantum brain events are suggested to occur at the whole brain level rather than the level of the synapses. In this system, conscious events are selected from the large-scale excitation of the brain. He speaks of a creative event bringing into being one of a range of possibilities that exist in Heisenberg’s quantum distribution of probabilities. The neural excitations are a code, and each experience is regarded as a selection from this code. The conscious brain is seen as a system that is internally determined in a way that cannot be represented outside the system, whereas in the rest of the physical universe an external representation of an object or system and knowledge of the laws of physics allow accurate predictions as to future events. Stapp views the brain as a self-programming computer with self-sustaining input from memory, which is a code derived from previous experience. This results in a number of probabilities from which consciousness has to select. The conscious act is a selection of a piece of top-level code, which then exercises control over the flow of neural excitation. Each human experience is accompanied by the activation of a top-level code. Evidence for Stapp's Model Stapp says that proof of his theory requires the identification of the neurons that provide the top-level code and also the mechanism by which the memory store is turned into further top-level code. The conscious events are seen as being capable of grasping a whole pattern of activity, and this in turn is seen as accounting for the unity of our consciousness. Stapp envisages a top level of brain processing involved with information gathering, planning of actions, choice of particular plans and execution and monitoring of these plans. It is suggested that each top-level event is linked to a psychological event, which connects the psychological to the quantum. Each human conscious experience is seen as a ‘feel’ of an event in the top level of processing in the human brain. Consciousness & Chance Stapp sees the physical world as a structure of tendencies or probabilities within the world of the mind. He thinks that the introduction of an irreducible element of chance into nature via the collapse of the wave function, as described in most forms of quantum theory, is unacceptable. The element of conscious choice is seen by him as removing chance from nature. Henry Stapp Lawrence Berkeley National Laboratory, University of California, Berkeley Attention, Intention and Will in Quantum Physics Journal of Consciousness Studies, 6, Nos 8-9, pp. 143-64 Stapp starts by taking the view that the mind/matter problem represents a conflict between classical physics and our own intuitions. In classical physics we have to be automaton, while our intuition tells us that we are in charge of our actions. The dominant paradigm in neuroscience and philosophy is based on classical physics, and attempts to explain away the intuition of free will. Stapp, however, thinks it is necessary to bring in a form of quantum theory, which emphasises the importance of the observer. This allows a theory that is much closer to our intuitions. The need for a self-observing quantum system to ask particular questions produces a causal opening for mind/brain dynamics. Classical Physics & Consciousness Classical physics was based on the concept of bits of material localised in small regions, with all of the motion of these bits of matter determined by other bits of matter. The local character of this form of physical law was a central feature. The localised bits of matter respond only to their immediate neighbours, and not at all to more distant objects. The evolution of the physical universe is governed by the totality of local processes. This makes it difficult to discuss consciousness, which is a large-scale property of brains. However, in a system entirely driven by small scale interactions, there is nothing for the larger scale property of consciousness in the brain to do, or that it can do. Stapp takes the view that the success of classical physics in the 18th and 19th centuries has dazzled modern philosophers, so that they conceive it as part of their role to explain away consciousness. The dominant role of philosophers in the science of consciousness is itself interesting. While philosophers may have a useful role to play in interpreting science, it is difficult to think of another scientific area, where a hypothesis put forward by scientists and medical experts would be openly ridiculed without even the courtesy of advancing a decent argument against it. Stapp suggests that most modern philosophers make the assumption the classical physics is all they have to pay attention to. Stapp points out that the assumptions of classical theory are now known to be incorrect, albeit they represent a useful approximation of the truth. Stapp believes that quantum theory can provide a better understanding of the mind brain problem. The original Copenhagen Interpretation of quantum theory was thrashed out at the Solvay Conference of 1927. It was agreed that the wave function represented our knowledge of the system. Our knowledge, in this interpretation, is knowledge of a mathematical theory, and not knowledge of a real world of particles and fields. The mathematical formulas were to be seen as representing the knowledge of the human observers rather than external real events. The Copenhagen interpretation became the mainstream consensus for much of the 20th century, but it has become less invariably accepted in recent decades. Stapp, however, holds to an interpretation close to Copenhagen. Stapp discusses the amendments to Copenhagen introduced by von Neumann. Von Neumann brought the human observer into the physical system of the quantum state. However, the basic concept of Copenhagen was retained, that is that the quantum is to do with knowledge, and reductions in the quantum wave are necessary for any increase in knowledge. There is a link between the reduction of the quantum wave and an increase in knowledge in the consciousness of the observer. Stapp goes on further to discuss the role of the observer in traditional interpretations of quantum theory. The original Schrödinger equation does not specify where and when the question leading to reduction will come, or what the question is. The ‘Heisenberg choice’, favoured by Stapp, is Heisenberg’s 1927 idea that the observer in quantum theory chooses the questions that will be put to nature. The original Schrödinger equation does not specify where and when the question leading to reduction will come, or what the question is. Body Schema Stapp drawing on studies of infants assumes that humans have a hard-wired body-world schema. Consciously directed action is seen as a projection of this body-world schema into the future, with a corresponding representation in the brain. This body-world schema is seen as directing the unconscious brain, issuing commands for motor action and instructions for mental processing. On going questions to nature continue to be posed by the observer. This equates to the ‘Heisenberg choice’, where the human observer has to decide what question to put to nature. In this case it is the conscious processing in the brain that does this. Each experience leads to further updating of the system. When an action is initiated by a thought, this usually includes some monitoring of the subsequent action, to check it against the intended action. So something experienced as an intention becomes an action, the attention to which is also experienced. Stapp views the deterministic unfolding of matter according to the Schrödinger equation as running parallel to the movement from intention to attention, as two poles of the same quantum event. He also sees a tripartite structure being the Schrödinger equation, the Heisenberg choice of question to ask and the (Dirac) choice of answer from nature. Stapp’s point is that only a conscious observer within the brain can ask the question, and drive the quantum process. This also allows the experiental process to enter into the causal structure of the body/brain. Stapp feels that some additional process is needed and the conscious observer is a perfect candidate. He sees quantum theory as informational in nature and thus linked to increments in knowledge occurring in the brain. The increment in knowledge is seen as linked to a reduction in the quantum state, thus linking mind to the physical world. Mind is thus seen as entering into the physical world through the Heisenberg choice. When the quantum state is reduced a wave that extends over an indefinite amount of space is instantaneously reduced to a tiny local region. Stapp feels that this constitutes a representation of knowledge rather than a representation of matter. The wave before collapse is seen as a matter of potentiality or probabilities, which are themselves often conceived as ideas rather than realities. However, the quantum state pre-collapse evolves in line with the deterministic Schrödinger equation, giving the state some of the properties of the physical, thus and creating in fact a sort of hybrid. Stapp does not suggest that our conscious thoughts are completely unconstrained, but he does see our thoughts as a part of the causal structure of the mind-brain that is not dominated by the actions of the smallest components of the brain, but is also not a random effect. Our thoughts are seen not as linked to external objects, but instead linked to patterns of brain activity. Stapp points out that his theory has a place for an efficacious conscious mind linked to the physical processes of the brain. In the latter part of his article, Stapp does attempt to address the problem of what happened when there were no human minds to poses questions of nature. He suggests that the dynamic of the Schrödinger evolution, which is to produce an event that replicates the event that produced, it could somehow stand in for the later action of conscious minds. On the surface of it, this does not seem very convincing, since the rest of article has been stressing the difference between the questions posed by conscious minds and their timing on the one hand and the determinism of classical physics as applied to the brain on the other hand. The identity theory of mind claims that each mental state is identical to some process in the brain. However, classical physics says that the entire causal structure of a physical system is determined by the microscopic level of the physical structure, so that larger scale effects such as consciousness cannot have any influence. The problem with Stapp’s theory and with the whole Copenhagen influenced interpretation of quantum theory is the apparent dualism. Mathematics can be seen as a mental process instantiated in protein, which cannot directly influence the external world. Somehow the mathematical description of the quantum waves is sitting out there in space, and then as a result of a measurement becomes a physical particle. The problem is really the same as with dualism. In Copenhagen, a mental concept external to the body becomes physical with no explanation as to how the two could interact. In dualism, the spirit stuff and the material stuff are supposed to act on one another, but it is not clear how, without one taking on some of the characteristics of the other, at which point the system is no longer dualistic. The Copenhagen system has the additional problem of what was happening before human minds emerged to perform measurements, for which Stapp’s explanation appears rather sketchy. References:- (1) Dennett, Daniel A Companion to the Philosophy of Mind ed Samuel Guttenplan Blackwell Schwartz, J. (1999) A role for volition and attention in the generation of new brain circuitry Journal of Consciousness Studies, 6, (8-9) pp. 115-42 Stapp, Henry P. (1972) The Copenhagen Interpretation American Journal of Physics, 40, pp. 2098-2116 Stapp, Henry P. (1993) Mind, Matter and Quantum Mechanics Springer Verlag Stapp, Henry P. (1998a) Pragmatic approach to consciousness Brain and Values ed. Karl Pribram von Neumann, J. (1932) The Mathematical Principles of Quantum Mechanics Princeton University Press (1955) Wigner, E. (1961) The probability of existence of a self-reproducing unit The Logic of Personal Knowledge, ed M. Polyani Routledge & Kegan Paul David Bourget University of Toronto Quantum Leaps in Philosophy of Mind Journal of Consciousness Studies, 11, 12, 2004, pp. 17-42 In this article, David Bourget attacks Stapp’s theory of quantum consciousness. First he discusses some of the difficulties posed by quantum theory itself. He regards von Neumann’s 1955 version as the final version of the orthodox view of quantum theory. This distinguishes the collapse of the quantum wave from the evolution of the wave. The collapse of the wave is here related to a measurement. The evolution of a system subject to a measurement is termed a projection postulate. It is not deterministic, in that the state that the system evolves into is not determined by the current state which is the wave function. However, probabilities can be assigned to the various possible outcomes. Stapp refers to these types of measurement as empirical questions. The questions have to have yes or no answers in response to questions about observables, such as ‘is the particle at position P’? In contrast to the actual collapse of the wave function, the evolution of the wave is determined by Schrödinger’s equation, and specifies deterministically what state the system will be in in the future providing no measurement takes place. This system represents a superposition of states that an observable could be in. What the theory does not define is what processes occur when the wave function collapses. The theory does not state when a measurement should occur. It is left to the mind of an experimenter to decide the timing, make the measurement, and apply the projection postulate. Nor does the theory specify what type of measurement should be made. This is again left to the mind of the experimenter, but the choice of type of measurement has an important impact on the future development of the system. In the orthodox theory there is also a problem as to where the collapse takes place between an original photon collision and the subsequent neural events in an observers mind. Stapp, who claims to follow Heisenberg’s interpretation, sees the collapse of the wave function as a real event, which draws a dividing line between the potentials of the quantum world and the objects of the classical world. Freewill Stapp criticises the classical view of freewill, because it leaves no room for the conscious will to determine actions. The universe would be no different if it did not exist in the view of classical physics. He favours a theory that frees the will from domination by the lowest level of physical objects, which is what happens in the classical theory, and he looks to quantum theory for an explanation. Stapp’s original view of how free will functioned in the brain drew on the ideas of Eccles (1994)(1). This relates to the release of neurotransmitters from the boutons at the end of axons. The bouton contains vesicles holding neurotransmitters. A nerve impulse, or fluctuation in electrical potential in the axon, causes an influx of calcium ions into the bouton, which set off a process that triggers a release of neurotransmitters into the synaptic cleft. Eccles pointed out that normally only one vesicle released its neurotransmitters, although there could be as many as 50 vesicles potentially able to release neurotransmitters. Eccles suggested that the mind exerted control at the quantum level by tuning the grid that holds the vesicles. Stapp suggests that the calcium ions could be in superposition. However, Bourget thinks that if indeterminancy did arise at individual synapses they would average out across the brain. Stapp, however, thinks that indeterminacies could be amplified across the brain into large patterns. He envisages self-sustaining neural groups driven by these indeterminacies. Eventually the strongest signal is extracted from competing signals, so the original intervention of the mind at the neurotransmitter level can be amplified up. The choice open to the mind is to choose which probability emerges from the wave function collapse, but it cannot specify anything else in this theory. Bourget claims that Stapp altered his view of freewill during the 1990’s According to Bourget, it is only in the later versions of his theory that Stapp says that freewill is not involved in the collapse of the wave function, but only in the inderterminacies of quantum measurement. Stapp thinks that the indeterminancies as to the timing of a quantum measurement leave scope for freewill. Stapp sees the freedom of the will as limited to asking or not asking a particular question, such as ‘am I moving a finger? The frequency with which the will asks questions of the system can alter the dynamics of the brain system. (Misra and Sudarshan 1977) (Joos, 1996) (Itano et al 1990) (2-4). The Unity of Consciousness Stapp concentrates on the unity of consciousness. He thinks that this requires a physical correlate that does not exist in classical physics. Stapp relates this to quantum non-locality, where the collapse of the wave function of one particle, decides the outcome of the collapse of another, even though the latter is out of range of a signal travelling at the speed of light, or any other physical contact. Because of its unity, consciousness cannot be seen as the action of separate particles, but as holistic collpases over large parts of the brain. Stapp defines our experience of consciousness as the feeling of events in the top-level processing of the brain. Qualia are defined as non-decomposable patterns of neural activity, while intentional states are seen as combinations of such patterns. Stapp draws a distinction between qualia such as the redness of red, the elemental or absolute units of experience and the meanings or intentional states that arise from the basic units of qualia. Bourget considers that decoherence may present a problem for Stapp’s theory. He points out that the brain, in Stapp’s theory, seems to wander between the superposed yes and no answers to questions until freewill holds it onto either a yes or a no answer. Bourget thinks that Stapp’s account implies superpositions not only of brain macrostates but of their environment. References:- Atmanspacher, H. Quantum Zeno perception Biological Cybernetics Barrett, J (1999) The Quantum Mechanics of Minds & Worlds Oxford University Press Ghiradi, G et al (1990) Continuous spontaneous reduction model involving gravity Physical Review A, 42, pp. 1057-64 Giulini, D. (1996) Decoherence and the appearance of a classical world in quantum theory Springer Libet, B. et al (1983) Time of conscious intention to act Brain, 106, pp.623-42 Libet, B. (1999) Do we have free will? Journal of Consciousness Studies, 6 (8-9) pp. 47-57 Lockwood, M. (1989) Mind, Brain & Quantum Oxford University Press Stapp, H. (1993) Mind, Brain and Quantum Mechanics Springer-Verlag Stapp, H. (1995) Why classical mechanics cannot accommodate consciousness in Scale in Conscious Experience ed. J. King and K. Pribram Stapp, H (1996a) The Hard Problem Journal of Consciousness Studies, 3 (3) pp. 194-210 Stapp, H (1996b) The Evolution of Consciousness Proceedings of Towards a Science of Consciousness Tucson conference Stapp, H (1997) Science of consciousness and the hard problem The Journal of Mind and Behaviour, 18 (2-3), pp. 171-94 Stapp, H (1999) Attention, intention and will in quantum physics Journal of Consciousness Studies, 6, 8-9, pp. 143-64 Stapp, H. (2000) The importance of qunatum decoherence in brain processes www-physics.lbl.gov/~stapp/stappfiles.html Stapp, H. (2001) Quantum Theory and the role of mind in nature Foundation of Physics, 31, pp. 1465-99 Stapp, H. (2002) The basis problem in many-world theories Canadian Journal of Physics, 80, 1043-52 von Neumann, J (1955) Mathematical Foundations of Quantum Mechanics Princeton University Press Wigner, E. (1962) Remarks on the mind-body question in the Scientist Speculates ed. I.J. Good Wigner, E. (1973) Epistemological perspective on quantum theory in Contemporary Research in the Foundations of Quantum Theory ed. C. A Hooker Henry Stapp Lawrence Berkeley Laboratory Quantum Leaps in Philosophy of Mind: Reply to Bourget’s Critique Journal of Consciousness Studies, 11, No. 12, pp. 43-9 In this paper, Stapp addresses Bourget’s criticism of the idea, derived from von Neumann, that the original Copenhagen interpretation of quantum theory needed to be supplemented by the conscious choice of the observer. Stapp stresses that he adheres to orthodox physics and disagrees with Eccles suggestion that the physical law can be biased by a non-physical mental effort. Stapp says that his objective is to identify how patterns of neural excitation are excited. Stapp considers that the selection contains a willful element and a statistical element. The willful element is the so-called Heisenberg choice. The second part is what the physicist, Dirac, referred to as ‘a choice on the part of nature’. Stapp’s theme is that the collapse of the wave function that results in the particular position of a particle being chosen is not determined by the laws of quantum theory. In the von Neumann interpretation of quantum theory the timing of the wave function collapse is determined by the experimenter and the choice of position for the particle, the projection operator, is random. Stapp sees these elements as providing a dynamical gap that allows mental effort to influence brain activity. He thinks that the choice of when the wave function collapse occurs, and what the projection operators decides is a joint effort of the mental and physical aspects of the brain. Freewill comes in at this level which is not statistically controlled. In particular, Stapp thinks that mental effort could effect the rapidity of the collpase of the wave function, and this is relevant to findings in psychology and neuroscience that have a bearing on mental effort and will (Schwartz et al, 2003) (1). Stapp moves on to discuss the difficult question of what is the mental agent that determines the rapidity of collapse. In practical terms, this is mental effort, but what is this mental effort. Stapp does not rule out the possibility of discovering a physical determinant of the wave function collapse, but points out that science has not been able to find this during a period of 25 years, because the mathematical basis of the theory ties it to probabilities rather than certainties. In Copenhagen the evolving wave function is not enough to specify reality, and human choices have to enter into the flow of events. Thus choice comes not from a mechanical process, but partly from an evaluative process, which is what we experience as happening. There could be two reservations with regard to Stapp’s work. First, it is based on a version of Quantum Theory which is close to Copenhagen. Many modern physicists dislike this approach, mainly because of the dualistic way in which the real universe somehow arises from mathematical concepts. Even if this is allowed, on the basis that it is still to some extent a mainstream interpretation of physics, the theory is blatantly dualistic in that the mental agent the decides the rapidity of the wave function collapse is stated to be most likley non-physical. References:- (1) Schwartz et al, (2003) The volitional influence of the mind on the brain in Consciousness, Emotional Self-Regulation and the Brain..ed. M. Beauregard John Benjamins Schwartz et al, (2004) Quantum physics in neuroscience and psychology Bourget, D. (2004) Quantum leaps in philosophy of mind Journal of Consciousness Studies, 11 (12) pp. 17-42 Stapp, H (1993) Mind, Matter and Quantum Mechanics Stapp, H. (1997) Science of consciousness and the hard problem Journal of Mind and Behaviour, 18, (2-3) pp. 171-94 Stapp, H. (1999) Attention, intention and will in quantum physics Journal of consciousness Studies, 6, (8-9) pp. 143-64 Stapp, H. (2001) Quantum Theory and the role of mind in nature Foundation of Physics, 31, pp. 1465-99 Stapp, H. (2004) Quantum approaches to consciousness in Cambridge Handbook of Consciousness ed. M. Moskovitch & P. Zelato www.physics.lbl.gov Stapp. H. (2004) The Mindful Universe Henry Stapp Theoretical Physics Group, Lawrence Berkeley Laboratory, University of Caligornia This article comprises Stapp’s response to Chalmers views on consciousness. Stapp’s view of consciousness is that while in the future neuroscientists may be able to identify particular correlates of consciousness, it will be impossible to deduce from the principles of classical mechanics that these correlates must be accompanied by the conscious experience of feeling, because such feeling is never mentioned in classical mechanics. Reductionist neuroscience and articicial intelligence are both very fond of the idea that increasing complexity somehow leads to consciousness. This can take either the form that complexity leads to this extra state not mentioned in classical physics, or that certain complex calculational structures somehow simply are consciousness, although neither of these ideas were ever stated in classical physics. The idea that certain logical structures as in computers amount to consciousness is known as functionalism. Stapp says that in functionalism two things, the operation of the brain and qualia such as pain are said to be the same thing. He says it is not helpful in discussing pain that we have known since childhood, to say that the feeling that we have does not exist, or to say that they do not exist as feelings, but are simply patterns in the brain. Stapp then goes on to look at the situation in quantum mechanics. He adheres to the traditional Copenhagen interpretation of quantum theory or something close to it. This system brought the conscious experience of observers into physics. The Copenhagen Interpretation is not interested in the reality of the particles involved but in the observers experience of them. This orthodox interpretation sees that quantum waves as merely abstract systems for predicting what observers can expect to experience. Neils Bohr saw our experience as the final data, and science as being to do with the correlation of data. Experience is thus a primitive fact in ortodox quantum theory, which is absent in classical physics. Einstein opposed this view, wanting to grasp physical reality independent of any observer. Stapp sees the quantum collapse of the wave function state at a high level covering the whole of the impending action of an organism and this is suggested to correpond to an experiental effect. The brain is seen to proceed by periods of unconscious processing punctuated by conscious events. Each conscious event chooses from a range of possibilities allowed by the previous unconscious processing. The act of choosing seems to be equated to the actual conscious experience. A person or possibly self is seen as a serious of discrete experiences bound together by the physical body. He does not agree with the view that the self is an illusion, because he sees it bound together by the continuity of the body and the memory store. Stapp does not see the randomness of the quantum wave collapse as a problem, because he views what happens as a choice between plans of action drawn up by the organism as a unit. References:- Bohr, Niels (1934) Atomic Physics and Human Knowledge Cambridge University Press Bohr, Niels (1958) Essays on aomic physics and human knowledge Wiley Heisenberg, Werner (1958) Physics and Philosophy Harper and Row Stapp, H. (1972) The Copenhagen Interpretation American Journal of Physics, 62, pp. 880-7 Stapp, H. (1993) Mind, Matter and Quantum Mechanics Springer Verlag Stapp, H. (1994) Strong versions of Bell’s Theorem Physical Review, A49, 3182-7 Stapp, H. (1995) Quantum coherence, resonance and mind Proceedings of Symposa in Applied Mathematics Wigner, Eugene (1961) Remarks on the mind-body problem in Ed. Good, I. The Scientist Speculates Heineman |
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