Unfortunately, most of the prevailing descriptions of quantum theory tend to emphasize puzzles and paradoxes in a way that
makes philosophers, theologians, and even non-physicist scientists leery of actually using in any deep way the profound changes
in our understanding of human beings in nature wrought by the quantum revolution. Yet, properly presented, quantum mechanics
is thoroughly in line with our deep human intuitions. It is the 300 years of indoctrination with basically false ideas about
how nature works that now
makes puzzling a process that is completely in line with normal human intuition. I therefore begin with a non-paradox-laden
description of the quantum universe and the place of our minds within it.
The founders of quantum mechanics presented this theory to their colleagues as essentially a set of rules about how to make
predictions pertaining to what we human observers will see, or otherwise experience, under certain specified kinds of conditions.
Classical mechanics can, of course, be viewed in exactly the same way, but the two theories differ profoundly in the nature
of the predictions they make.
In classical mechanics, the state of any system – at some fixed time, t – is defined by giving the location and the velocity of every particle in that system, and by giving also the analogous information
about the fields. All observers and their acts of observation are simply parts of the evolving, fully predetermined, physically
described universe. Within that framework the most complete prediction pertaining to any specified time is simply the complete
description of the state of the universe at that time. This complete description is in principle predictable in terms of the
laws of motion and the complete description of the state of the universe at any other time.
Viewed from this classical perspective, even the form of the predictions of quantum mechanics seems absurd. The basic prediction of quantum theory is an answer to a question of
the following kind: If the state of some system immediately before time t is the completely specified state #1, then what is the probability of obtaining the answer ‘Yes’ if we perform at time t an experiment that will reveal to us whether or not the system is in state #2?
Classical physics gives a simple answer to this question: the predicted probability is unity or zero, according to whether
or not state #2 is the same as state #1. But quantum theory gives an answer that generally is neither unity nor zero, but
some number in between.
The quantum structure is easily understood if we follow Heisenberg’s idea of introducing the Aristotelian idea of
potentia.
A
potentia, in Heisenberg’s words, is an ‘objective tendency’ for some event to happen. Everything falls neatly in place if we assert
– or simply recognize – that the quantum state of a system specifies the ‘objective tendency’ for a quantum event to happen,
where a
quantum event is the occurrence of some particular outcome of some particular action performed upon the system. In short, the quantum state
is best conceived
in principle exactly as it is conceived
in actual practice, namely as a compendium of the objective tendencies for the appearances of the various physically possible outcomes of the
various physically possible probing actions. Once the action to be performed upon the system is selected, the objective tendencies
are expressed as probabilities assigned to the various alternative possible outcomes of that chosen action.
If one accepts as fundamental this Aristotelian idea of potentia – of objective tendencies – then the whole scheme of things becomes intuitively understandable. There is nothing intrinsically
incomprehensible about the idea of ‘tendencies’. Indeed, we build our lives upon this concept. However, three centuries of
false thinking has brought many physicists and philosophers to expect and desire an understanding of nature in which everything
is completely predetermined in terms of the physically described aspects of nature alone. Contemporary physics violates that classical ideal. Bowing partially to advances in physics, these thinkers have accepted
the entry of ‘randomness’ – of mathematically controlled chance – as something they can abide, and even embrace. However,
there remains something deeply galling to minds attuned to the conception of nature that reigned during the eighteenth and
nineteenth centuries. This is the possibility that our human minds can introduce elements of definiteness into the description
of nature that the physically described processes of nature, acting alone, leave unspecified.
The causal incompleteness of the physically described aspects of nature entailed by this possibility is something that many
physicists, philosophers, and neuroscientists will go to extreme lengths to try to circumvent. Yet, such attempts all boil
down, at present, to
‘promissory materialism’, for no one has yet shown how the interventions of our minds – or some surrogates – required by contemporary
orthodox quantum theory can consistently be eliminated.
This seemingly unavoidable entry of mental realities into the laws of physics arises in connection with the choice of which
(probing) action will be performed on a system being observed. Quantum theory places no conditions, statistical or otherwise,
on these choices. Consequently, there is a ‘causal gap’ in orthodox contemporary physics. This gap is not in the choice of
an outcome, which is mathematically controlled, at least statistically. It is rather in the choice of which of the physically possible
probing actions will be undertaken. But the choices of which actions a person will make are exactly the choices that are important
to religion, and more generally to moral philosophy. Thus orthodox contemporary physical theory offers a conception of nature
that enforces, in a rationally coherent and massively confirmed way, everything that physics says about the structure of human
experience, while leaving open the vitally important question of how we choose our actions from among the possibilities proffered
by the causally incomplete physical laws.
A main source of confusion in the popular conception of quantum mechanics is a profound misunderstanding of the connection
between the large and the small. One repeatedly hears the mantra ‘quantum mechanics concerns very small things, whereas consciousness
is related to large-scale activities in the brain; therefore quantum mechanics is not relevant to the problem of the connection
between mind and brain’.
Actually, the basic problem resolved by orthodox quantum theory is precisely the problem of the connection between invisible
small-scale activities and the large-scale activities that are more directly connected to conscious experience. The atomic-scale
aspects of nature considered alone are unproblematic: they are governed by local deterministic laws that are well understood
and logically manageable. It is only when the consequences of the atomic-level processes are extended to the macro level (for
example, to Schrödinger’s cat, or to Geiger counters, or to human brains) that the radically new quantum features come into
play. It is only
then that one encounters the seismic shift from a continuous deterministic process to the Heisenberg/Aristotelian notion of the
potentia for psycho-physical events to occur.
The deeper aspects of quantum theory concern precisely the fact that the purely physical laws of motion that work so well
on the atomic scale fail to account for the observed properties of large conglomerations of atoms. It is exactly this problem of the connection between physically described small-scale properties and directly experienced large-scale properties
that orthodox quantum theory successfully resolves. To ignore this solution, and cling to the false precepts of classical
mechanics that leave mind and consciousness completely out of the causal loop, seems to be totally irrational. What fascination
with the weird and the incredible impels philosophers to adhere, on the one hand, to a known-to-be-false physical theory that
implies that all of our experiences of our thoughts influencing our actions are illusions, and to reject, on the other hand, the offerings of its successor, which naturally produces an image of ourselves that is
fully concordant with our normal intuitions, and can explain how bodily behaviour can be influenced by felt evaluations that emerge from an aspect of reality that is not adequately conceptualized in terms of the mechanistic notion of bouncing
billiard balls?
Decoherence effects are often cited as another reason why quantum effects cannot be relevant to an understanding of the mind–brain
connection. Actually, however, decoherence effects are the basis both of the mechanism whereby our thoughts can affect our
actions, and of the reconciliation of quantum theory with our basic intuitions.
The interaction of the various parts of the brain with their environment has the effect of reducing an extremely complex
conceptualization of the state of the brain to something everybody can readily understand. The quantum state of the brain
is reduced by these interactions to a collection of
parallel potentialities, each of which is essentially a classically conceivable possible state of the brain. The word ‘essentially’ highlights the
fact that each of the classical possibilities must be slightly smeared out to bring it into accord with Heisenberg’s uncertainty
principle: the potential location and velocity of the centre of each particle is smeared out over a small region. This conception
of the quantum brain is intuitively accessible, and it is made possible by (environment-induced) decoherence. This picture
of the brain captures very well the essence of the underlying mathematical structure, and it can be used with confidence.
According to this picture, your physically described brain is an evolving cloud of essentially classically conceivable potentialities.
Owing to the uncertainty principle smearing, this cloud of potentialities can quickly expand to include the neural correlates
of many mutually exclusive possible experiences. Each human experience is an aspect of a psycho-physical event whose psychologically
described aspect is that experience itself, and whose physically described aspect is the reduction of the cloud of potentialities
to those that contain the neural correlate of that experience.
These psycho-physical actions/events are of two kinds. An action of the first kind is a choice of how the observed system
is to be probed. Each such action decomposes the continuous cloud of potentialities into a set of mutually exclusive but collectively
exhaustive separate components. An action of the second kind is a choice ‘on the part of nature’ of which of these alternative
possible potentialities will be ‘actualized’. The actions of the second kind are predicted to conform to certain quantum probability
rules. An action of the first kind is called by Bohr ‘a free choice on the part of the experimenter’. It is controlled by
no known law or rule, statistical or otherwise.
Decoherence plays also another crucial role. The rules of quantum theory allow a person to pose the question, ‘Is my current
state the same as a certain one that I previously experienced?’ In the
important cases in which a person wants to perform a certain action, the freedom of choice allowed by quantum theory permits
that person to ask the question, ‘Is my current state the one that on previous occasions usually led to a feedback that indicated
the successful performance of that action?’ The answer may or may not be ‘Yes’. If the answer is ‘Yes’, then the neural correlate
of ‘Yes’ will be actualized. It is reasonable to assume that this neural correlate will be a large-scale pattern of brain
activity that, if actualized, will tend to cause the intended action to occur.
This tendency can be reinforced by exploiting the person’s capacity – within the framework of the quantum laws – to pose a question of his or her own choosing at any time of his or her own choosing. This freedom can be used to activate a decoherence effect called the quantum Zeno effect. This effect can cause the neural
correlate of the ‘Yes’ outcome to be held in place for longer than would otherwise be the case, provided the intentional effort
to perform the action causes the same question to be posed repeatedly in sufficiently rapid succession. The freedom to do
this is allowed by the quantum rules. The quantum Zeno effect is a decoherence effect, and it is not diminished by the environment-induced
decoherence: it survives intact in a large, warm, wet brain.
The upshot of all this is that the arguments that were supposed to show why quantum mechanics is not relevant to the mind–body
problem all backfire, and end up supporting the viability of a quantum mechanical solution that is completely in line with
our normal intuitions. One need only accept what orthodox quantum mechanics insists upon – to the extent that it goes beyond
an agnostic or pragmatic stance – namely that the physically described world is not a world of material substances, as normally
conceived, but is rather a world of potentialities for future experiences.
Given this new playing field, we may commence dialogues pertaining to the remaining, and vitally key, issue: namely the origin
and significance of the felt evaluations that seem to guide our actions. These evaluations appear to come from an experiential
or
spiritual realm, and are certainly allowed by quantum theory to have the effects that they seem to have. But before turning
to these core questions, it may be useful first to elaborate upon some aspects of the preceding remarks.
I claimed above that quantum mechanics, properly presented, and more specifically the quantum mechanical conception of nature,
is in line with intuition. It is rather classical physics that is non-intuitive. It is only the viewing the quantum understanding
of nature from the classical perspective, generated by three centuries of indoctrination, that makes the quantum conception
appear non-intuitive.
Some other speakers, following common opinion, have said just the opposite.
Ernan McMullin has given, in Chapter
2 of this volume, a brief account of the history, in philosophy and in physics, of the meaning of ‘matter’. Aristotle introduced
essentially this term in connection with the notion of ‘materials for making’, such as timber. The Neo-Platonists used it
in contrast to the ‘spiritual’ aspects of reality. In the seventeenth, eighteenth, and nineteenth centuries it became used
to denote the carrier of the small set of properties that, according to the then-ascendant ‘mechanical philosophy’, were the
only properties that were needed to account for all changes in the visible world. These properties, called ‘physical properties’,
were considered to be ‘objective’, in contrast to the ‘subjective properties’, which are ‘dependent in one way or another
on the perceiver’.
In Chapter
2 of this volume, McMullin describes the two millennia of philosophical wanderings and wonderings about the ‘stuff’ out of
which nature was built that occurred between the time of the Ionian philosophers and the invention of the classical conception
by Isaac Newton. This account makes clear the fact that the classical conception of nature is not the direct product of innate
human
intuition. Schoolchildren need to be
taught that the solid-looking table is ‘really’ mostly empty space, in which tiny atomic particles are buzzing around. And this
conception leaves unanswered – and unanswerable in any way that builds rationally upon that classical conception – the question:
How do our subjective experiences of the visible properties emerge from this conceptually and causally self-sufficient classically
conceived reality?
The deepest human intuition is not the immediate grasping of the classical-physics-type character of the external world. It
is rather that one’s own conscious subjective efforts can influence the experiences that follow. Any conception of nature
that makes this deep intuition an illusion is counterintuitive. Any conception of reality that cannot explain how our conscious
efforts influence our bodily actions is problematic. What is actually deeply intuitive is the continually reconfirmed fact
that our conscious efforts can influence certain kinds of experiential feedback. A putatively rational scientific theory needs
at the very least to explain this connection in a rational way to be in line with intuition.
As regards the quantum mechanical conception, McMullin calls it ‘problematic’ and ‘counterintuitive’. In Chapter
5 of this volume, Seth Lloyd calls it ‘counterintuitive’ and ‘weird’. Let me explain why the opposite is true: why contemporary
opinion, to the contrary, is the product of a distorted viewpoint that is itself counterintuitive, but has, in spite of its
serious technical failings and inadequacies, been pounded into ‘informed’ human thinking by 300 years of intense indoctrination.
The original (Copenhagen) interpretation of quantum theory was pragmatic and epistemological: it eschewed ontology. It avoided
all commitments about what really exists! Von Neumann retained and rigorized the essential mathematical precepts of the Copenhagen
interpretation but, by developing the mind–matter parallelism of the Copenhagen conception, brought the bodies and brains
of the human observer/experimenter into the world understood to be made of atoms, molecules, and the like. Von Neumann’s formulation
(called ‘the orthodox interpretation’ by Wigner) prepared the way for an imbedding ontology. This extension made by von Neumann
is the basis of all attempts by physicists to go beyond the epistemological/pragmatic Copenhagen stance, and give an account
of the reality that lies behind the phenomena.
Bohr sought to provide an adequate understanding of quantum theory, and our place within that understanding, that stayed strictly
within the epistemological framework. Heisenberg, however, was willing to opine about ‘what was really happening’.
Reality, according to Heisenberg, is built not out of matter, as matter was conceived of in classical physics, but out of
psycho-physical
events – events with certain aspects that are described in the language of psychology and with other aspects that are described
in the mathematical language of physics – and out of
objective tendencies for such events to occur. ‘The probability function … represents a tendency for events and our knowledge of events’ (Heisenberg,
1958, p. 46). ‘The observation … enforces the description in space and time but breaks the determined continuity by changing our
knowledge’ (pp. 49–50). ‘The transition from the “possible” to the “actual” takes place during the act of observation. If
we want to describe what happens … we have to realize that the word “happens” can apply only to the observation, not to the
state of affairs between two observations’ (p. 54). ‘The probability function combines objective and subjective elements.
It contains statements about possibilities or better tendencies (
potentia in Aristotelian philosophy), and these statements are completely objective: they do not depend on any observer; and it contains
statements about our knowledge of the system, which of course are subjective, in so far as they may be different for different
observers’ (p. 53).
Perhaps the most important change in the theory, vis-à-vis classical physics, was its injection of the thoughts and intentions
of the human experimenter/observer into the physical dynamics: ‘As Bohr put it … in the drama of existence we ourselves are
both players and
spectators … our own activity becomes very important’ (Heisenberg,
1958, p. 58). ‘The probability function can be connected to reality only if one essential condition is fulfilled: if a new measurement
is made to determine a
certain property of the system’ (p. 48 [my italics]). Bohr: ‘The freedom of experimentation … corresponds to the free choice of experimental
arrangement for which the mathematical structure of the quantum mechanical formalism offers the appropriate latitude’ (Bohr,
1958, p. 73).
This ‘choice on the part of the “observer”’ is represented in the mathematical formalism by von Neumann’s ‘process 1’ intervention
(von Neumann,
1955, pp. 351, 418). It is the first – and absolutely essential – part of the process leading up to the final actualization of
a new ‘reduced’ state of the system being probed by the human agent. This process 1 action partitions the existing state,
which represents a continuous smear of potentially experienceable possibilities into a (countable) set of experientially distinct
possibilities. There is nothing known in the mathematical description that determines the specifics of this
logically needed reduction of a continuum to a collection of distinct possibilities, each associated with a different possible increment of
knowledge. Also, the
moment at which a particular process 1 action occurs is not specified by the orthodox quantum mathematical formalism. This choice of
timing is part of what seems to be, and in actual practice is, determined by the observer’s free choice. These basic features of
quantum mechanics provide the basis for a rational and natural quantum dynamical explanation of how a person’s conscious effortful
intents can affect his or her bodily actions (Beauregard, Schwartz, and Stapp,
2005; Stapp,
2005; Stapp,
2006).
Many of our conscious experiences are associated with a certain element of intent and effort, and it may be that
every conscious experience, no matter how spontaneous or passive it seems to be, has
some degree of focusing of attention associated with it. An increase in the effortful intention associated with a thought intensifies
the associated experience. Hence it is reasonable to assume that an
application of effort increases the repetition rate of a sequence of essentially equivalent events.
If the rapidity of the process 1 events associated with a given intent is great enough, then, as a direct consequence of the
quantum laws of change, the neural correlate of that intent will become almost frozen in place. This well-known and much studied
effect is called the ‘quantum Zeno effect’.
The neural correlate of an intent to act in a certain way would naturally be a pattern of neural activity that tends to cause
the intended action to occur. Holding this pattern in place for an extended period ought strongly to tend to make that action
occur. Thus a prominent and deeply appreciated gap in the dynamical completeness of orthodox quantum mechanics can be filled
in a very natural way that renders our conscious efforts causally efficacious.
By virtue of this filling of the causal gap, the most important demand of intuition – namely that one’s conscious efforts
have the capacity to affect one’s own bodily actions – is beautifully met by the quantum ontology. And in this age of computers,
and information, and flashing pixels there is nothing counterintuitive about the ontological idea that nature is built – not
out of ponderous classically conceived matter but – out of events, and out of informational waves and signals that create
tendencies for these events to occur.
Whitehead deals with the undesirable anthropocentric character of the Copenhagen epistemological position by making the associated
human-brain-based quantum objective/subjective events into special cases of a non-anthropocentric general ontology (Whitehead,
1978, pp. 238–239).
Perhaps the main basis for the claim that quantum mechanics is
weird is the existence of what Einstein called ‘spooky action at a distance’. These effects are not only ‘spooky’ but are also
absolutely impossible to achieve within the framework of classical physics. However, if the conception of the physical world
is changed from one made out of tiny rock-like entities to a holistic global informational structure that represents tendencies
to real events to occur, and in
which the choice of which potentiality will be actualized in various places is in the hands of human agents, there is no spookiness
about the occurring transfers of information. The postulated global informational structure called the quantum state of the
universe is the ‘spook’ that does the job. But it does so in a completely specified and understandable way, and this renders
it basically non-spooky.
In short, the quantum conceptualization is not
intrinsically counterintuitive, problematic, or weird. It becomes these things only when viewed from a classical perspective that
is counterintuitive because it denies the causal efficacy of our intentional efforts, is
problematic because it provides no logical foundation upon which a rational understanding of the occurrence of subjective experience
could be built, and is
weird because it leaves out the mental aspects of nature and chops the body of nature into microscopic, ontologically separate
parts that can communicate and interact only with immediate neighbours, thereby robbing both conglomerates and the whole of
any possibility of fundamental wholeness or meaningfulness. It is the von Neuman process 1 actions that inject the elements
of wholeness and meaning into the quantum universe: without these acts there is nothing but a continuous smear of meaningless
un-actualized possibilities (Stapp,
2007a,
2007b).
Information, from the quantum theoretical perspective, is carried by the physical structure that communicates the potentialities
created by earlier psycho-physical events to the later ones. This communication of potentialities is an essential part of
the process that creates the unfolding and actualization in space and time of the growing sequence of events that constitutes
the history of the actual universe. Information resides also in the psychologically described and physically described aspects
of these events themselves, and is created by these events.
The information that is created in a computational process imbedded in nature resides in the bits that become actualized in this process. This growing collection of bits depends upon
the partitionings of the quantum smear of possibilities that constitute the universe at some instant (on some space-like surface in the relativistic
quantum field theory description) into a set of discrete yes–no possibilities with assigned probabilities. The actualized
bits specify the tendencies for future creations of bits. The partitionings specified by the process 1 actions thus lie at
the base of the computational notion of information.
But how can these process 1 actions be understood? The partitioning of a continuum into a particular (countable) set of discrete
subsets requires a prodigiously powerful choice. This motivates the assumption that the descriptions that appear to be continuous within contemporary quantum theory must really be discrete at some underlying level, provided mathematical ideas
hold at all at the underlying level.
These processes of choosing are in some ways analogous to the process of choosing the initial boundary conditions and laws
of the universe. That is, the free choices made by the human players can be seen as miniature versions of the choices that
appear to be needed at the creation of the universe. Quantum theory opens the door to, and indeed demands, the making of these
later free choices.
This situation is concordant with the idea of a powerful God that creates the universe and its laws to get things started,
but then bequeaths part of this power to beings created in his own image, at least with regard to their power to make physically
efficacious decisions on the basis of reasons and evaluations.
I see no way for contemporary science to disprove, or even render highly unlikely, this religious interpretation of quantum
theory, or to provide strong evidence in support of an alternative picture of the nature of these ‘free choices’. These choices
seem to be rooted in reasons that are rooted in feelings pertaining to value or worth. Thus
it can be argued that quantum theory provides an opening for an idea of nature and of our role within it that is in general
accord with certain religious concepts, but that, by contrast, is quite incompatible with the precepts of mechanistic deterministic
classical physics. Thus the replacement of classical mechanics by quantum mechanics opens the door to religious possibilities
that formerly were rationally excluded.
This conception of nature, in which the consequences of our choices enter not only directly in our immediate neighbourhood
but also indirectly and immediately in far-flung places, alters the image of the human being relative to the one spawned by classical physics. It changes this
image in a way that must tend to reduce a sense of powerlessness, separateness, and isolation, and to enhance the sense of
responsibility and of belonging. Each person who understands him- or herself in this way, as a spark of the divine, with some small part of the divine power,
integrally interwoven into the process of the creation of the psycho-physical universe, will be encouraged to participate
in the process of plumbing the potentialities of, and shaping the form of, the unfolding quantum reality that it is his or
her birthright to help create.
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