Consciousness in David Bohm's ontology

Consciousness in David Bohm's ontology

by Paavo Pylkkänen

Consciousness Studies Programme

Department of Humanities
University of Skövde
P.O. Box 408
S-541 28 Skovde
Sweden
E-mail: paavo@ihu.his.se

Introduction

David Bohm was one of the foremost physicists of his generation and made significant contributions to e.g. plasma physics and the foundations of the quantum theory. As is well known, his interests and explorations extended far beyond physics. His biography Infinite Potential by David Peat, for example, makes it clear that a very primary interest in Bohm's life was with the question of how to bring about a good society. His engagement with physics, philosophy, social theory, religion and eventually a form of group dialogue all were strongly connected to his concern for "making the world a better place". It is fair to say that Bohm was most concerned about consciousness in the sense of trying to bring about a kind of mind and way of being that would contribute to an overall coherence and creative harmony for humanity. This is not to deny that a great deal of Bohm's work can be seen to be motivated by a more intrinsic interest, in the sense that the issues that are explored are taken to be interesting in themselves, without clear connections to the broader social aims. But it is important to appreciate just how central for Bohm was the concern with transforming society through transforming both individual and social consciousness. In this course our topic is "quantum approaches to consciousness", and on this I will now focus. However, references to Bohm's work concerned with the broader ideas are also made from time to time in the text below.

Our question in this lecture is: "What were David Bohm's ideas about the relationship between quantum theory and consciousness?" This is no easy question to answer, for Bohm's views about the quantum theory developed and changed, as did his views about the mind and consciousness.

I have written some new material for this lecture and also included some previously published material, as well as references to websites. There is in particular

1) Historical overview of Bohm's work on mind and matter , specifically written for this course (by Paavo Pylkkänen)

2) An exposition and analysis of Bohm's early (1951) analogies between quantum processes and thought, specifically written for this course (by Paavo Pylkkänen).

3) Web reference to Bohm's 1990 article "A New Theory of the Relation between Mind and Matter", originally published in the journal Philosophical Psychology. In this paper Bohm summarizes his quantum approach to mind and matter.

4) Web reference to the physicist Chris Dewdney's home page where you can find a good summary and visual illustrations of Bohm's "causal interpretation" of the quantum theory.

5) Introductory material to Bohm's quantum approach to mind, as well as a discussion of it (by Paavo Pylkkänen, modified for this course).

6) Web reference to Basil Hiley's overheads in the Tucson III conference, which make an overall presentation of the field of quantum approaches to consciousness, and explain some of his latest ideas on the topic.

7) A brief paper by Paavo Pylkkänen on Bohm's view of causality as it develops in the early 1960s in the Bohm-Biederman correspondence (Routledge, 1999).

1. Historical overview of Bohm's work on mind and matter

The idea of this section is to briefly review some of Bohm's major contributions relevant to "quantum approaches to consciousness". The following list is not meant to be exhaustive, but tries to give a basic orientation. It expands more on Bohm's lesser known work and is relatively brief in the well known work (e.g. the implicate order).

* 1940s -> groundbreaking contributions in some more standard areas of physics like plasma physics. Bohm suggested that the plasma behaved in some respects like a living organism. If you disturbed it it would shield itself etc.

* one of the clearest formulations of the "standard" interpretation of the quantum theory in his 1951 text book Quantum theory. Particular emphasis on making explicit the physical meaning of the theory (as opposed to a mere exposition of the mathematical formalism). Yet Bohm said that after writing the book he still felt he couldn't understand the theory well enough. The book also has a well known section where analogies between quantum processes and inner thought processes are discussed (to be considered in section 2 of this lecture).

* dissatisfaction with standard quantum theory catalyzed by discussions with Einstein led Bohm to "do the impossible" (Bell) - to offer a consistent alternative interpretation of the quantum theory, published in 1952 as two papers in the journal Physical Review. According to this intepretation a quantum system like an electron always a particle accompanied by a new type of field. This made possible an unambigous ontology where particles were moving under the action of not only classical potentials but also a new quantum potential. A striking non-classical feature was non-locality or action at-a-distance, a feature of quantum mechanics which Einstein, Podolsky and Rosen had made explicit in their 1935 attempt to argue against Bohr's conventional quantum theory. Because of the uncertainty principle it is not possible to verify Bohm's intepretation, and it remains partly a hypothesis about what might be going on where we are not able to look. At the same time it provides perhaps the most elegant account of the observed facts of the quantum theory, at least for those feel theories are allowed or even supposed to make assumptions about the unobservable to account for unintilligible observed facts.

Bohm called his approach initially a "hidden variable" interpretation, and a bit later he called it the "causal" intepretation. A yet another name used is "pilot-wave" interpretation. Actually de Broglie had proposed something very similar to Bohm's theory already in the 1920s under the title "theory of a double solution", but soon dropped the idea due to heavy criticisms especially from Wolfgang Pauli. Bohm was able to answer these and as a result de Broglie returned to develop his original approach. Thus it is common to refer to the view also as "de Broglie - Bohm interpretation". There one needs to remember that regardless of striking similarities there are also important differences. One of these is that de Broglie's view sees the electron as a singularity of a field, whereas Bohm's 1952 papers postulate the electron to have a particle aspect which exists over and above the wave aspect.

Bohm develops his approach in co-operation with e.g. Vigier and later on with Basil Hiley and their research students like Chris Dewdney at Birkbeck College, University of London. More description, references and "movies" of Bohm's approach, as well as a description of recent developments, can be found at Chris Dewdney's home page and you are recommended to check this out later on, in section 4 of the lecture at:

For an exposition of a more "mechanistic" line of development (known as "Bohmian mechanics") that has arisen from Bohm's work, see Sheldon Goldstein's home page.

The importance of Bohm's 1952 approach to the "quantum consciousness" debate arises especially thorugh a later re-intepretation of the model, where Bohm suggested that the wave aspect of the electron contains "active information" that in a subtle "non-mechanistic" way in-forms (rather than mechanically pushes and pulls) the particle aspect. In this week's lectures this idea will be extensively discussed, as follows. In section 3 of this lecture it is recommended that you read Bohm's own paper on the topic at

Paavo Pylkkänen's introduction into the approach and a discussion of Bohm's above paper is also included later on in this lecture, in section 5. Section 6 of the lecture then suggests that you go through Basil Hiley's overheads to the Tucson III meeting at

Let us go back to the historical overview. The next philosophically important step is

* the book Causality and Chance in Modern Physics (1957, republished by Routledge in 1984), where the causal interpretation is placed into a wider, non-mechanistic world-view, where "qualitative infinity of nature" is a key concept. The critics had accused Bohm for making a conservative step back towards the mechanical Newtonian deterministic physics in his 1952 "hidden variable" papers, and Bohm takes great pains to deny that his causal intepretation implies that nature is a deterministic machine. In a dialectical fashion he sees determinism and indeterminism as two sides of any process in nature. In some domains one of these sides, say, determinism may dominate so that a deterministic theory provides a correct account of that domain (e.g. in the domain of classical physics, there seems to be no principal limit to the accuracy in which we cann predict the behaviour of an individual system). Yet if one were able to see that process from "another side" or more precisely one would see indeterminate features coming in (e.g. the more accurate study of particles like electrons showed basic limitations in our ability to predict their behaviour, thus revealing the aspect of indeterminism). Bohm's controversial idea then was that in an even more accurate study, revealing a "sub-quantum level" we might well discover a new kind of determinism, and his 1952 causal interpretation showed one such possible deterministic model. But the key point was that even if some such model were found to be correct, it would not prove that nature is absolutely determinisitc, for Bohm's scheme suggests that we would be likely to find a new kind indeterminacy even at the sub-quantum level in an accurate enough study.

He emphasized that each theory in science is correct only with respect to a particular domain and that similarly, determinism and indeterminism are features of some limited domain (such as the domain of classical physics, quantum physics, subquantum etc.) The essence of "mechanistic philosophy" was defined as "...the assumption that the great diversity of things that appear in all of our experience, every day as well as scientific, can all be reduced completely and perfectly to nothing more than consequences of the operation of an absolute and final set of purely quantitative laws determining the behaviour of a few kinds of basic entities or variables. In this connection it must be stressed, however, that the mere use of a purely quantitative theory does not by itself imply a mechanistic point of view, as long as one admits that such a theory may be incomplete. Hence, mechanism cannot be a characteristic of any theory, but rather ... a philosophical attitude towards that theory" (pp. 38-9).

* in a correspondence with the American artist Charles Biederman he further develops his views about necessity and contingency, and begins to consider the concepts of order and structure as the fundamental concepts in the description of nature (Bohm and Biederman 1999). This reflects itself in 1965 papers such as "Space-Time considered as Discrete Structural Process" and "Problems in the Basic Concepts of Physics", in a paper on the notion of "order" in biology (1969) and eventually in two papers on the notion of the implicate order 1971 and 1973, which were republished in Wholeness and the Implicate Order (1980).

For a brief description of how necessity and contincency are understood in the BB correspondence, see my paper "Quantum interweavings", included as section 7 of this lecture.

* a paper discussing "The Problem of Truth and Understanding in Science" appears in Popper's Festschrift in 1964.

* discussions with the Indian-born teacher J. Krishnamurti begin in the early 1960s and continue till Krishnamurti's death in 1986. This offers Bohm, among other things, a "method" of introspection; consciousness and the possibilities of its transformation become a central focus of his work. Joint books are published, in particular The Ending of Time and The Limits of Thought (posthumously). The interest in Krishnamurti combines with Bohm's earlier concerns with the social dimension, and in the 1980s we see Bohm advocating a form of large group dialogue as means of social exploration, transformation and well-being.

* the 1965 text book The Theory of Special Relativity contains an appendix "Physics and Perception" which argues that Relativity describes human perceptual process better than Classical Physics. On the whole during this period we see in Bohm's writing more concern with trying to understand human mental processes as a special and developed case of general processes of "reflection" to be found in nature. The later discussions of consciousness in the context of the notion of implicate order bear a clear resemblance to these ideas in the early sixties, both in the Bohm-Biederman correspondence, the article "Space-Time considered as Discrete Structural Process" and in the appendix "Physics and Perception".

* the 1973 paper "Human nature as the product of our mental models" considers the idea that our mental reality is in some sense produced by our mental models. This anticipates the later (1980s) ideas, where meaning is seen as the key factor of being. A number of other philosophical and psychological papers appear in the mid 1970s.

* the 1977 paper "Science as Perception-Communication" summarizes Bohm's study of Bohr's interpretation of the quantum theory, where communication plays a central role. The book Fragmentation and Wholeness shows Bohm's concern with the mechanization of modern society. A new more holistic and process-like mode of language, the Rheomode, inspired by quantum theory is introduced. Another paper explores the implications of the idea that both reality and knowledge are considered to be processes.

* the book Wholeness and the Implicate Order of 1980 presents together six previously published papers and introduces a new one, titled "The enfolding-unfolding universe and consciousness". The Revision magazine features Bohm "holographic universe" alongside Pribram's holographic theory of the brain, and Renee Weber's interviews convey Bohm's approach to a wider public.

* the book Unfolding Meaning (1985) (edited by Donald Factor) includes the paper "Soma-significance" where meaning is seen as a key factor of being. The ideas about dialogue in the sense of a special form of group process begin to take concrete shape. The book Changing Consciousness with Mark Edwards presents Bohm's approach to the human condition. Later publications along similar lines include the posthumously published book On Dialogue.

* the anthologies Beyond Mechanism (ed. by D. Schindler) and Physics and the Ultimate Significance of Time: Bohm, Prigogine and Process Philosophy include important articles by and on Bohm.

* the paper "A new theory of the relation between mind and matter" (1986) presents the idea of active information for the first time.

* The book Science, order and creativity (1987) with David Peat presents a popular account of many of Bohm's ideas.

* Bohm's festschrift Quantum Implications (edited by Hiley and Peat) comes out 1987. In his own paper Bohm explains the relationship between the hidden variables and the implicate order. A number of other papers by eminent authors discuss issues relevant to "quantum consciousness.

* in the paper "Meaning and information" in the anthology The Search for Meaning (1989) he further develops the ideas of soma-significance and active information. A developed version of the paper "A New Theory of the relationship between mind and matter" appears in the journal Philosophical Psychology in 1990. See
(this paper is also recommended reading for this lecture, see section 3 below)

* Bohm has discussions with the biologist Rupert Sheldrake, where interesting connections are explored between "formative fields" in physics and biology. These are published in the 2nd edition of Sheldrake's book The New Science of Life.

* Bohm reconsiders his ideas on cognition in the late 1980s and early 1990s in co-operation with Paavo Pylkkänen, who is writing a PhD on Bohm and cognitive science. The co-operation results in a manuscript of an article, which is not completed due to Bohm's death 1992. It may be published posthumously in some form.

* Completed before Bohm's death in 1992, The Undivided Universe with Basil Hiley (Routledge, 1993) summarizes the work on the ontological intepretation and explores new developments thorugh the notion of implicate order, also discussing the mind-matter relationship. The book is hailed by C.J. Isham as "One of the most important works on quantum theory during the last twenty years".

* David Peat's biography of Bohm, Infinite Potential appears in 1994.

* posthumous publications include On Creativity (edited by Lee Nichol, Routledge), which includes many articles on mind. The first volume of the Bohm-Biederman correspondence (ed. by P. Pylkkänen) is published by Routledge in 1999. Bohm's widow, Mrs Saral Bohm has played a key role in helping this as well as other posthumous publications to appear.

As already mentioned, one of the difficulties of stating Bohm's quantum approach to consciousness is that he explored many differents views of quantum theory, opening up different ways to discuss consciousness in a quantum context. It is easy to confuse these different ideas with each other. Before discussing the 1951 analogies, let me therefore briefly summarize how Bohm's mind-matter ideas from different periods relate to the different views of quantum theory that he explored.

Phase 1: the conventional interpretation of the quantum theory

* until 1951 Bohm was the supporter of the "conventional" interpretation of the quantum theory, Bohr's approach in particular. Thus his 1951 discussion of analogies between thought and quantum processes are based on the conventional approach and must not be confused with those of his later (1980s) ideas on mind and matter (e.g. active information) that arise from a re-interpretation of his own 1952 causal or ontological interpretation.

Phase 2: hidden variables and the qualitative infinity of nature

* the 1952 papers on hidden variables do not explicitly discuss the mind-body problem. But they are philosophically relevant because they present a "realist" alternative to the prevailing "positivist" Copenhagen view. That is, Bohm argues that unlike Bohr had claimed, it is both possible and meaningful to think about quantum processes at the level that we cannot observe. This is a typical tension between realism and positivism, and Bohm explicitly mentions positivism as his opponent in the papers. The philosophical point is that Bohm tries to show that there exists a mind-independent well-defined reality at the quantum level in the sense that particles, for example have a well-defined position and momentum. The quantum world exists ontologically independently of the human mind, and the quantum world gives rise to the classical world in situations where the effect of the quantum potential is negligible. In contrast Bohr and others had claimed that quantum theory gives us an epistemological lesson, in the sense that we are not justified in assuming the existence of a well-defined physical reality at the quantum level, independently of the observational phenomena that are known to us; and those observational phenomena do not reveal a well-defined quantum world, but only certain features (like position) at one context, while others equally important (like momentum) are unobservable (complementarity).

One of the characteristic features of philosophy since Kant has been to emphasize the role of the human mind in constructing our experience of the world and to be silent about the nature of the unobserved and unobservable world that is not constructed by us. In this general sense Bohr clearly belongs to the Kantian tradition, as did the positivist (though see e.g. Plotnitsky's book Complementarity for considerations that Bohr also radically breaks away from the Kantian tradition) . Scientific realists, on the other hand, oppose Kant and the positivists and claim that it is possible to know the "real world", at least to a certain approximation (truthlikeness or verisimilitude). Bohm is clearly a representative of scientific realism in his 1952 papers.

Commentators like Stapp have been keen to note that Bohm's 1952 approach leaves out the mind of the observer from the physical universe. However, this would only follow if Bohm claimed that his version of the quantum theory is a final and complete description of the physical universe, and this he didn't claim or even imply. But perhaps the point was not made clear enough in the 1952 papers, given that so many people took Bohm to represent simplistic determinism and even a kind of elimination of consciousness from the scientific view of the world.

* in any case already in the 1957 book Causality and Chance in Modern Physics Bohm explicitly professes the view that no theory can ever plausibly be considered complete, due to his assumption that the universe is infinite not only in a quantitative but also in a qualitative sense. He clearly makes room for the existence of consciousness in the physical world, although he doesn't discuss what consciousness is and how it relates to the physical world.

Phase 3: Back to the conventional interpretation of qm and towards the Implicate Order

* partly as a result of heavy criticisms of the 1952 causal interpretation and partly as a result of not seeing how to develop the approach further, Bohm seems to give up the causal interpretation for a number of years, and starts to reconsider Bohr's approach, as well as to consider a wider framework in which the different contradictory theories of physics (especially quantum theory and general relativity) could be reconciled. This leads later on to the idea of the implicate order. It is very important to realize that the ideas of the implicate order are in some respects more similar to Bohr's approach than to Bohm's own 1952 approach. For example, Bohm begins to consider in 1960s that we must give up the traditional notion of space-time. In the early papers from mid-1960s one finds references to Bohr's discussion of the indivisibility of the quantum of action as important in this context but no references to Bohm's own 1952 work. Bohm's concept of mind as a highly developed process of "reflection" (in some ways similar to "reflection" occuring at the level of physics, with light etc.) begins to emerge in those papers in the mid-1960s, but the 1952 causal interpretation does not seem to play any significant role in that period. Thus one might say that the sort of "quantum approach to consciousness" that Bohm presents in the final chapter of the book Wholeness and the Implicate Order is in some ways more in the line with Bohr's approach than it is in the line of his own 1952 approach.

phase 4: the grand synthesis: active information and the implicate order

* Bohm started to reconsider the 1952 work in the late 1970s and it is only in the 1980s that we see Bohm developing a "quantum approach to mind" in relation to the re-intepreted 1952 causal interpretation, with the suggestion that the quantum field contains "active information" which guides the particle aspect. To understand how Bohm himself looked at the relation between the 1952 approach and the implicate order, it is worth reading his own paper in his Festschrift Quantum Implications. The idea is that eventually one could look at "active information" as an example of the implicate order, and that both concepts are necessary to work out the Bohmian approach to mind and matter. But given that Bohm's views changed a lot, it is no easy task to spell out the "grand synthesis". Indeed, it seems that Bohm felt that these ideas were very much in the early stages of development.

With these remarks in mind, let us now move on to consider Bohm's 1951 ideas about analogies between quantum processes and thought.

2) Analogies between thought and quantum processes (1951)

Probably Bohm's first published remark on the relation between quantum theory and thought processes can be found in the text book Quantum theory (1951, pp. 168-172). Here is a summary and a brief discussion of those ideas.

2.1 Three different analogies

a) Effects of observation

"If a person tries to observe what he is thinking about at the very moment that he is reflecting on a particular subject, it is generally agreed that he introduces unpredictable and uncontrollable changes in the way his thought proceeds thereafter."

This is similar to the effects of observation at the quantum level. In other words, the way observation of thought introduces unpredictable and uncontrollable changes in the way thought proceeds thereafter.

is analogous to

the way observation of the position of a particle introduces unpredictable and uncontrollable changes in the particle's momentum.

For example, let us ask a person to give a detailed description of what he is thinking about while reflecting on some definite subject. The "paradox" is that as soon as he begins to give this detailed description, he is no longer thinking about the subject in question, but is instead thinking about giving a detailed description.

The idea is that the thought process does not allow itself to be observed beyond a certain approximate level without changing in a significant way.

The analogy with quantum level observation could be a mere coincidence. But one alternative is that the physical aspect of thought involves quantum processes in some crucial way. This would explain in a qualitative way why the direction ("momentum") of thought is disturbed by an attempt to define the content ("position") of thought. This applies especially in the debate about the interpretation of the quantum theory, for there it is widely held that as you define your position, you lose your momentum... :-)

b) Relationality of being (indivisibility)

"...if a person attempts to apply to his thinking more and more precisely defined elements, he eventually reaches a stage where further analysis cannot even be given a meaning". This leads Bohm to suggest that

A part of the significance of each element of thought processes originates in its indivisible and incompletely controllable connections with other elements.

which is analogous to

The way some of the essential properties of a quantum system (e.g. whether it is a wave or a particle) depend on indivisible and incompletely controllable connections with surrounding objects.

Similarly, "...part of the connotation of a word depends on the words it is associated with, and in a way that is not, in practise, completely predictable or controllable (especially in speech). In fact the analysis of language, as actually used, into distinct elements with precisely defined relations between them is probably impossible."

Comment: Again, this analogy could just be a coincidence. But if the physical aspect of thought and language were essentially involving quantum processes, some holistic features of language and meaning would get a qualitative naturalistic explanation.

c) Logic and causal laws, concepts and objects, nonlogical discovery and quantum jump

The thought process is analogous to the classical limit of the quantum theory.

"The logical process corresponds to the most general type of thought process as the classical limit corresponds to the most general quantum process."

The rules of logic are analogous to the causal laws of classical physics.

"Logically definable concepts play the same fundamental role in abstract and precise thinking as do separable objects and phenomena in our customary description of the world."

"Yet, the basic thinking process probably cannot be described as logical."

Sudden emergence of a new idea is analogous to a quantum jump.

Comment: The idea here is that the structure and operation of the human mind reflects the dual nature of the reality out of which the mind emerges. According to Bohm the classical world of separable objects and phenomena governed approximately by the causal laws of classical physics is a real but not the most fundamental aspect of the physical world. The more fundamental level is the quantum level where features like quantum jumps are central. And just as the physical world at the classical limit can be thought to consist of separable objects and phenomena governed by classical laws, so the human mind has a "classical level", a level of logical thought process which consists of logically definable concepts governed by the rules of logic. Yet this is not the full story about the physical world nor about the human mind. In the physical world at the quantum level, the classical notion of separable objects is not generally applicable, neither are causal laws of the classical type. Instead the essential properties of a quantum system (e.g. whether it is a wave or a particle) depend on indivisible and incompletely controllable connections with surrounding objects. The traditional idea of a separable object thus breaks down at the quantum level. Also, processes are radically different from processes at the classical level (e.g. because of quantum jumps). Similarly for Bohm the "most general type of thought process" cannot be described as logical, and it would be natural to suggest that logically definable concepts are not applicable to the basic thinking process.

So, just as there are , if you like, two physical worlds (the general quantum world and the special case of a classical world) so there are two minds (the mind in the sense of a general alogical and aconceptual thinking process and the special case of the mind as logical thinking process with logically definable concepts).

We have the quantum world of inseparable objects and discontinuous processes, and the classical world of separable objects and causal, continuous processes.

We have the aconceptual mind (cf. Pylkkö, The Aconceptual Mind, John Benjamins 1998) with alogical processes and the conceptual mind engaged in logical thinking as a special case of it.

Again, we have a strong analogy, and one explanation of it would be provided if it is the case that the physical aspect of the alogical, aconceptual thought process involved quantum processes (with inseparability and discontinuity), while the physical aspect of the logical and conceptual thought process involved classical processes (e.g. classically describable neural "activation patterns" governed by the classical laws of physics).

This last analogy is perhaps the philosophically most sophisticated one, for recent analyzes in the philosophy of mind and of cognitive science have shown the importance of the non-conceptual or aconceptual level of the human mind. The interesting question is what might be the physical or computational concomitants of non-conceptual processes, and connectionism has been pointed to as a candidate. Yet there are arguments that connectionist models are mechanically computable and thus deterministic which would make them an implausible candidate for the physical aspect of a truly non-mechanical level of aconceptual mental processes.

2. 2 Is the analogy between quantum processes and inner experiences / thought processes a mere coincidence?

"Bohr suggests that thought involves such small amounts of energy that quantum-theoretical limitations play an essential role in determining its character."

Much of the enormous amount of mechanism in the brain must probably be regarded as operating on a classically describable level. But "...Bohr's suggestion involves the idea that certain key points controlling this mechanism (which are, in turn, affected by the actions of this mechanism) are so sensitive and delicately balanced that they must be described in an essentially quantum-mechanical way."

If Bohr's hypothesis could be verified, it would explain in a natural way a great many features of our thinking.

"If it should be true that the thought processes depend critically on quantum-mechanical elements in the brain, then we could say that thought processes provide the same kind of direct experience of the effects of quantum theory that muscular forces provide for classical theory."

"We suggest that ... the behavior of our thought processes may perhaps reflect in an indirect way some of the quantum-mechanical aspects of the matter of which we are composed."

Bohm might have added that logical thought processes reflect and perhaps give us some experience of processes in the classical domain, given that he emphasized the analogy between these two in the previous section.

Note that in these remarks Bohm is not directly addressing the "hard problem" of consciousness but is rather focussing on the nature of the thought process. The first point concerns how the thought process behaves when it is "observed"; the second concerns the underlying holistic character of the thought process; and the third notes that there is both a "general" and a "classical" aspect to thought, just as there is a general and a classical aspect to physical processes.

Given that thought processes and quantum processes have so much in common, then perhaps this is so because in some respects they are the same process.

Note that the critics of "quantum consciousness" sometimes claim that people in the approach think "consciousness is a mystery, quantum mechanics is a mystery, perhaps they are the same mystery?". But even Bohm's 1951 remarks argue that quantum processes and mental processes are not only mysterious but share certain basic properties in common, so much so that we are led to think that they to some extent at least are the same process.

3) Bohm's 1990 article "A New Theory of the Relation between Mind and Matter"

It is now recommended that you read this article. It was originally published in the journal Philosophical Psychology. In this paper Bohm summarizes his quantum approach to mind and matter.

4) Chris Dewdney's summary and visual illustrations of the Bohm interpretation of the quantum theory.

It is now recommended that you check out Dewdney's website at

5) More introductory material to Bohm's quantum approach to mind by Paavo Pylkkänen

This material is useful to you especially if you have little background in the topic. The text discusses in particular Bohm's 1990 article (section 3) but includes a broader philosophical perspective as well.

**will be added shortly **

6) Basil Hiley's overheads in the Tucson III conference

Here is an overall presentation of the field of quantum approaches to consciousness, and an explanation of some of Hiley's latest ideas on the topic. It is recommended that you first read the "Pre-conference workshop slides" and then the plenary talk slides.

7) "Quantum interweavings" by Paavo Pylkkänen

This is a brief paper on Bohm's view of causality as it develops in the early 1960s in the Bohm-Biederman correspondence (Routledge, 1999). The paper was originally written for Dr. Ivan Havel's 60th birthday volume (to be published) in 1998.

QUANTUM INTERWEAVINGS

Paavo Pylkkänen
Department of Humanities
University of Skövde
P.O. Box 408
S-541 28 Skovde
Sweden
E-mail: paavo@ihu.his.se

Ivan Havel and I first met in 1991. We shared an interest in David
Bohm's work and what Ivan likes to call a "transdisciplinary " approach.
My own graduate work dealt with applying quantum theory to the mind-matter
problem and the like and I was very encouraged by Ivan's open and
supportive attitude - after all many researchers still think you are being
non- rather than trans- or inter-disciplinary when you want to work across
and beyond the boundaries of established disciplines. Over the years we
have managed - often jointly - to organize a number of small meetings and
workshops to nurture the transdisciplinary conspiracy.
I'd like to congratulate Ivan on his birthday by briefly discussing
one of the big questions of this century, that of determinism vs.
indeterminism in quantum theory, and by evaluating Bohm's role in this
debate. Towards the end of the paper I will take a transdisciplinary
turn...

1. Indeterminism vs. determinism in quantum physics

The determinism of Newtonian physics was an important cornerstone of the
mechanistic world picture, and for many the most radical feature of the
quantum revolution in physics was the failure to predict the behaviour of
individual quantum systems such as electrons. From this failure to
predict it was generally inferred that such systems have genuinely
indeterministic features. Of course, there is much about, say, electrons
and atoms that appears as straightforwardly determined, properties such as
mass or charge of the electron or energy levels of the atom. Further, in
a two-slit experiment a sufficiently large number of electrons produce a
precisely predictable interference pattern. And even the behaviour of an
individual electron is determined in the sense that we can predict what it
will not do: for example it will not go to certain areas of the
photographic plate in a two-slit experiment. Yet the fact that we cannot
predict just where in the possible areas it does appear in the plate is an
example of the radical kind of unpredictability that is also behind the
more generalized notion that individual processes at the most basic level
of nature known to us are genuinely indeterministic.
It is against this background that one needs to understand the
significance of Bohm's 1952 papers on hidden variables, presenting a
"causal interpretation of quantum theory" for a first time in a consistent
way. Bohm did not, of course, find a way of predicting where, say, an
electron will appear in a typical interference experiment. Nor has anyone
since been able to do that - quantum unpredicatibility and the uncertainty
principle still reign regardless of important advances in technology (e.g.
advances in observing individual atoms with lasers). What Bohm did was to
produce a model which showed that regardless of our inability to predict
it is still a coherent and physically consistent possibility that the
behaviour of electrons actually is determined. Here one must remember
those who, like von Neumann, had presented proofs that such models are
simply inconsistent with the quantum formalism, a formalism that had
gained tremendous experimental support. What Bohm established was that it
is ultimately a matter of faith whether or not one makes the assumption of
genuine indeterminism within the quantum domain. Quantum experiments and
formalism do not rule out the possibility that electrons, after all, move
deterministically along trajectories, being in this respect like their
macroscopic cousins, the billiard balls. Yet given that the inability to
predict still reigns in the domain of individual quantum systems, faith in
indeterminism seems more justified on the basis of the empirical data than
faith in determinism. Or is this just a matter of taste?
Bohm's 1952 work - and the work along these lines that followed it
- is an important contribution to our knowledge. It is important
precisely because, by offering a deterministic alternative as a
possibility, it brought out clearly that the commitment to genuine quantum
indeterminism is ultimately a matter of faith. But as is well known it
did not gain Bohm much respect amongst his colleagues back in 1952 - it
was felt by many that he was turning the clock back. It was quite common
to mention Bohm as an example of someone who was so attached to
determinism that he was unwilling to go along with the indeterministic
part of the quantum revolution. Today we can see, in various ways, more
appreciation of the 1952 work. There is, for example, a research activity
known as "Bohmian mechanics" which develops the approach and finds its
deterministic features an advantage rather than a drawback. This
development further backs up the impression of Bohm as one of the key
supporters of determinism in contemporary physics.


2. Bohm's view of determinism and indeterminism as interwoven categories

The fact about Bohm's attitude towards determinism is, however, more
complex than the above discussion suggests. There is no denying that Bohm
was eager to prove the possibility of a deterministic description of
quantum systems. Yet a study of his more philosophical writings reveals
that he was equally keen to understand the role of indeterminism and even
genuine indeterminism in nature. This was already brought out in his 1957
book Causality and Chance in Modern Physics where he argued that
determinism and indeterminism are aspects of a more general law. These
ideas were then discussed and developed further in a correspondence he had
during 1960-1969 with the American artist Charles Biederman, the first
part of which will be published in 1998 by Routledge as the book
Bohm-Biederman Correspondence (hereafter BB). I believe that these letters
provide an important clarification of Bohm's notion of determinism and
indeterminism.
The reason why the interaction with Biederman brings out Bohm's
views on indeterminism so clearly is the fact that Bohm and Biederman
disagreed about the status of indeterminism. For Biederman indeterminism
was subjective in the sense that it only arose in the meeting of human
beings and nature, while he assumed nature without human beings to be
determinate. This prompted Bohm to very clearly spell out in which sense
he thought indeterminism to be an objective property of nature. So here
we can see Bohm taking the opposite role, that of defending indeterminism
rather than questioning it. Indeed, this kind of dialectical approach
seems to have been much more important to Bohm than attachment to any
particular category such as determinism. Yet even in light of the
Bohm-Biederman correspondence it seems that for Bohm the totality of the
universe is determined and I guess this defines him as some sort of a
determinist. But it is certainly a very weak form of determinism.
Consider, for example, the following excerpt by Bohm:

"Of course, you might say that each event is determined necessarily in a
complete totality. But this would be trivial. For to give the complete
totality, you would have to give each event, so that the determination of
that event wouldn't add very much to it. Rather, necessity and
determination have real content, only insofar as they operate within
fields of abstration." (BB, p. 164)

Thus, for example, Bohm's 1952 causal interpretation should not be taken
as offering in principle a complete description of the totality of the
universe at the basic quantum level, but rather as a description of
determinism that may operate within a limited "field of abstraction", in
this case the quantum domain. Bohm assumed that the quantum determinism
he proposed would very likely dissolve into chance in some broader field
or sub-quantum domain. The notion of "fields of abstraction" is
elaborated earlier in the same letter:

"...the existence of fields of abstraction is characteristic of nature's
structure and order. The partial and relative dependence and independence
of these fields is also characteristic of nature. Therefore, in each
field, there must be contingency and chance. What is chance in one field
may be necessary in a broader field and vice versa. But all thought
functions in fields. Therefore, we will never get rid of chance and
contingency in our thought. But this is not purely the result of our own
way of thinking. For this way of thinking is based on the existence of
fields of abstraction in nature... There is genuine contingency, insofar
as functioning in fields is valid." (BB, p. 162-3)


The above excerpts have been taken out of a context in which the various
concepts have already been discussed from different angles, and thus they
are likely to appear somewhat cryptic here. The key point is, however,
that determinism and indeterminism are for Bohm complementary concepts
that obtain a real, as opposed to trivial, meaning only when we are
discussing a part or a partial field of the totality of the universe.
Dividing the universe into parts has always the risk of introducing
dualisms which seem impossible to interweave back together, thus creating
an unfortunate fragmentation to our world view - the dualism between mind
and body being perhaps the most notorious case. Yet if we do not
introduce divisions, what is there to say? Bohm's dialectical approach is
perhaps best summarized in the following excerpt:

"The truth about the cosmos is to be asserted by first asserting its unity,
by then asserting its duality in terms of opposing categories, and then
showing the interwoven unity of two duals." (BB, p. 50)

In this way determinism and indeterminism are for Bohm an example of
opposing categories which are both needed for a non-trivial understanding
of the universe. It is in understanding their mutual relationship, how
they interweave, that we obtain a non-trivial understanding of natural
process. Other categories that he uses in a similar way throughout the
correspondence with Biederman include actuality and possibility, finite
and infinite, law and lawlessness and regularity and irregularity.

3. Interweaving mind and matter

Perhaps this kind of dialectical method would be a useful addition to many
contemporary debates, say in the philosophy of mind. The mind-body
problem indeed becomes sharp by Descartes asserting the duality of mind
and matter in terms of opposing (mutually exclusive) categories:
non-extended, thinking and indivisible mental substance is separated from
extended, non-thinking and divisible material substance. The fact that it
has been difficult to show the "interwoven unity" of the Cartesian
opposites does not mean that this could not work for some other way of
distinguishing the mental and the physical. Contemporary philosophy of
mind, however, often sees dualism as a bad thing and opts for some form of
materialism with the unfortunate result that in most theories of the mind
the mind is left out, as Searle (1992) sarcastically points out. Perhaps a
different attitude in which one is not trying to eliminate or reduce one
category to obtain monism would be more fruitful. Searle's own "biological
naturalism" starts from an outright denial of the dualism between mind and
matter, insisting that the mind is a biological category. Yet it may be
Searle's inability or unwillingness to distinguish the mental from the
physical in a satisfactory way at the start of his approach which leaves
some of his readers unconvinced. We are given the "right answer" ("mind
is a biological category") at the very start of the inquiry but we do not
understand how it is a biological category. In Bohmian terms, the
Searlian mind doesn't interweave properly with the Searlian brain.
Bohm himself discussed the mind-matter issue with pairs of concepts
such as implicate vs. explicate, soma vs. significance and subtle vs.
manifest. He also proposed ways of seeing how these categories interweave:
the "explicate", for example can be seen as a special case of the
"implicate". I believe that a further study of such categories (or
similar ones yet to be developed) and their relationship is likely to
throw some new light upon even such a perennial problem as the mind-matter
one.

Bibliography

Bohm, D. (1952) "A Suggested Interpretation of the Quantum Theory in Terms
of Hidden Variables I & II", Phys. Rev., 85, no. 2, 166-193, Republished
in Quantum Theory and Measurement, Ed. by J. A. Wheeler and W. H. Zurek,
369-96, Princeton University Press, (1983)

Bohm, D. (1984) Causality and Chance in Modern Physics, London, Routledge
and Kegan Paul (new edition of work first published by RKP in 1957).

Bohm, D. (1980) Wholeness and the Implicate Order, London, Routledge and
Kegan Paul.

Bohm, D. and Biederman, C. (1998), Bohm-Biederman Correspondence. Volume
One: Creativity and Science, Edited by Paavo Pylkkanen, Routledge, London.

Bohm, D. and Hiley B.J. (1993), The Undivided Universe: An Ontological
Interpretation of Quantum Mechanics, Routledge, London.

Pylkkanen P. et. al eds. (1997) Brain, Mind and Physics, IOS Press, Amsterdam.

Searle, J. (1992) The Rediscovery of the Mind, MIT Press, Cambridge, Mass.