( not too sure where I found this bit of information, but am sure you'll enjoy it )
I shall introduce my problem with the help of that well tried Philosopher's
device, the imaginary world. Let us suppose that we have two parallel
coexisting universes. Universe A is our actual familiar universe and so, for
the moment, we need say no more about it. Universe A' is an exact physical
replica of A such that for every physical object that exists in A there is a
corresponding object in A' and for every physical event that occurs in A
there is a corresponding physical event in A'. The one and only feature
which serves to distinguish between A and A', apart from their spatial
separation, is the fact that in A' there are no mental entities Or conscious
experiences. Thus, although the whole of evolution and the whole of history
unfolds in A' exactly as it does in A, so as to be indistinguishable to an
observer, there are no observers in A', no one indeed who is aware of
anything that happens there, if to be aware is to have a conscious
experience.
I am here assuming that being conscious entails having a mind although
having a mind does not necessarily imply being conscious, there is, I would
say, nothing self-contradictory in the idea of unconscious mental events.
However, consciousness is, by common consent, the most distinctive attribute
of mind and it would be hard to make sense of a mind that never at any time
became conscious. At all events Universe A' is, ex hypothesi, a purely
physical or totally mindless universe.
Given this hypothetical situation we can now state our problem as follows:
Why should our actual world correspond with Universe A rather than with
Universe A'? If this is a valid question it admits of only two answers.
Either there is no reason at all, it is just a God-given or contingent fact
that that is how things actually are, like the fact that anything at 11
should exist rather than nothing, or else there is some reason, for example
we might suppose that the world we know could not have evolved as it has
done had it not been for the intervention of mind.
The first answer, that from an a priori standpoint A and A' are equally
probable candidates for actualisation, presupposes that mind plays no part
in the determination of physical events. The second answer which asserts
that A' is no more than a logical possibility and could never be actualised
implies that mind has some degree of autonomy in determining the course of
events. Materialism is a name that has been given to a variety of a
doctrines but, as I shall use the word here, a materialist is one who is
logically committed to giving the first answer. Similarly, what I shall call
Interactionism will here be taken to mean the doctrine which logically
commits one to giving the second answer. The purpose of the present paper is
to examine these two doctrines and assess their relative merits. I shall try
to show that there are no insuperable or logical objections to either of
them, whatever may have been said to the contrary, and that there are
manifold advantages and disadvantages whichever one we adopt. Accordingly in
present circumstances it must remain a matter of one's personal
philosophical predilections which of them one chooses (my own happens to be
for the second but I shall try not to let that influence the argument).
However, with the growth of knowledge, circumstances may change and I will
end by discussing what would need to be the case before it became more
rational to prefer one or other given alternative.
Before I can even embark on this plan, however, we must first consider very
carefully whether the hypothetical situation we took as our point of
departure is indeed a legitimate one and is not perchance vitiated by some
internal inconsistency or conceptual incoherence as many might protest. It
is after all only too easy to think up situations which, on examination,
turn out to be logical absurdities. We have only to think of that favourite
device of the science-fiction writer, time-travel. This seems innocuous
enough when it is first introduced into the narrative but very soon we are b
eset by all kinds of insoluble paradoxes. Could it be that our imaginary
world, Universe A', was in fact just such another flawed fantasy ?
Like time-travel, one must admit that it has some very bizarre consequences.
Consider the following thought-experiment.
We take an individual P, let him be a family man, from Universe A and
suddenly and instantaneously we exchange him with his counterpart P' from
Universe A'.
The first thing we may note about this thought-experiment is that it
produces absolutely no observable differences to indicate that anything
whatever has changed. P's wife and children will never know P' is not the
husband or father whom they knew and cherished, that indeed he is not a
person at all but an insentient automaton. For, ex hypothesi, nothing in the
appearance or behaviour of P', no far-away look in his eyes or anything of
that sort can ever betrays the secret to which we are privy. Likewise, if we
follow the adventures of P flow transposed to A', we know that he can never
discover his solipistic predicament, he will continue to believe that the
beings which he takes to be his wife and children have minds like his own.
But while this is certainly bizarre, it generates no paradox of a logically
objectionable kind. It is absurd only because A' is an absurd universe, our
thought-experiment has done no more than make explicit the well known truism
that no object however life-like and no behaviour however mind- like can
ever entail the presence of consciousness. It is true that, on any
positivist criterion of meaning, our thought-experiment must be dismissed as
meaningless since it is in principle impossible to verify that it has been
carried out. And yet, provided we can understand the distinction between A
and A', P and P', the supposition that such an exchange has been made is
perfectly intelligible. Indeed the intelligibility of such a
thought-experiment could well be advanced as a conclusive refutation of the
positivist theory of meaning.
In view of what has just been said it is surprising to find how large a
slice of the recent literature on the philosophy of mind would, in defiance
of the truism which we have just enunciated, disallow the distinction we
have made. I suppose the two most important doctrines in this connection are
(1) Logical Behaviourism (Ryle 1949) and (2) Central State Materialism
(Armstrong 1968). If, therefore, we can deal with the objections from these
sources we may feel reasonably confident that we stand on firm ground.
Now, according to the former, what it means for an organism to be conscious
or sentient is nothing over and above its being disposed to react to
situations in an appropriate or discriminating way. The elimination of any
existential element from consciousness by means of this stipulative
redefinition of the concept derives such plausibility as it may possess from
the ambiguity of the word consciousness as used in everyday discourse when
it is seldom necessary to distinguish between the behavioural criteria for
the ascription of consciousness and consciousness as such. Thus, when the
doctor is called in to pronounce whether the victim of the accident is
conscious or not we are normally quite content to accept his verdict as
final. And yet, logically, it is perfectly permissible to surmise that even
when the most refined physiological tests known to medicine show that the
patient is comatose, that is behaviourally unconscious, he may nevertheless
be experiencing some vivid hallucination or out-of-body experience and hence
conscious in the basic sense. It is, of course, exclusively in the basic
sense, not in the derived behavioural sense, that the inhabitants of our
Universe A' are said to be unconscious.
We should note, at this point, that it is only in its derived sense that we
can define or explicate what we mean by consciousness. In its basic sense it
can no more be defined than any other primitive concept. With any primitive
concept, either one understands what is intended or one fails to understand.
A logical behaviourist may be defined as someone who has failed to grasp
what consciousness means in this sense. Confronted with a logical
behaviourist various strategies may be adopted in order to get him to
understand what we mean. A nice example is that suggested by Kirk (1974) who
asks us to imagine ourselves converted step by step into a "Zombie" (his
name for our counterpart in A') by losing one sense-modality after another
while continuing to behave in a normal fashion. However, if all such
strategies fail and our logical behaviourist persists in denying that he
understands what we are talking about, the dialogue can go no further; all
that we can then do is to echo Dr Johnson when he declared that while he
could give his opponent an argument he could not give him an understanding.
But, if we reject Logical Behaviourism, then, by the same token we must also
reject Central State Materialism which equally refuses to recognise the
primary connotation of consciousness. Indeed, the latter doctrine differs
from the former only in that it literally identifies the mental states and
processes with the relevant brain states and processes. Mentalistic talk, we
are told, is essentially 'topic-neutral', by itself it tells us nothing
about its ontological reference, however science gives us the authority to
go beyond this neutrality and construe it as referring to the activities of
the brain. But if that were so there would be absolutely nothing that we
could say about the inhabitants of A that we could not equally say about the
inhabitants of A' since, ex hypothesi, they have identical brains. As it is,
however, we have said that the former have conscious experiences while the
latter do not. For those to whom this statement is intelligible both of
these proffered solutions of the mind-body problem are non-starters.
The two viable forms which materialism may take are, first, the
old-fashioned epiphenomenalism which regards the mind-brain relationship as
a causal relationship but one in which the causation works in one direction
only so that mental events figure only as effects, never as causes, and,
secondly, the more recent double-aspect or double-attribute theory, as it is
variously known, according to which the mind-brain relationship is one of
actual identity, that is to say mental events are conceived of as brain
events but as such events are apprehended by the brain itself as opposed to
the way in which they are apprehended by an external observer (i.e. by
another brain). This latter theory differs from the Central State version of
the identity theory in that it treats consciousness as an irreducible fact,
not as something needing to be analysed in dispositional terms. Various
conceptual advantages have been claimed for it over the earlier
epiphenomenalist theory but whether, in the last resort, anything more is
involved than a mere verbal shift or, indeed, whether it even makes sense to
talk about an identity in this context is still very much open to question.
These are not questions, however, which we need pursue here for, whether we
say that the mind is a function of the brain or whether we say that it is
the brain in one of its aspects, the explanatory weight rests wholly upon
the physical processes involved. Hence both forms of materialism carry the
same implication, namely that even if, per impossibile, the brain did not
generate conscious experiences or even if it had no other aspect than the
physical one, even so everything else would go on exactly as before.
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2
Despite repeated attempts by philosophers to discover some knock-down
argument which would show, once for all, that materialism or interactionism,
as the case may be, was an untenable position, the persistence of both
suggests that such attempts have been less than successful. The problem to
which we must now address ourselves is which position has the greater claim
on our allegiance, all things considered?
The immediate difficulty is that, traditionally, materialism takes its stand
on, and draws its strength from, science whereas, traditionally,
interactionism appeals to our common sense or moral intuitions. It is true
that interactionism as a doctrine was first formulated by Descartes who was
also one of the chief architects of the scientific revolution but he may
have been swayed by his religious commitments, certainly his doctrine held
little attraction for his successors. At all events, by the late 19th
Century, at a time when science had reached a peak of self-assurance and was
pressing its right to be considered the final arbiter on the nature of man,
epiphenomenalism had become the orthodox scientific position on the
mind-body issue and, in effect, it has remained so ever since.
Meanwhile those philosophers who could not embrace materialism gravitated
for the most part to one or other form of Idealism. From this lofty vantage
point science itself could be viewed, not as the one objective authority
which alone can legitimate our beliefs, but as just one of the creative
manifestations of the human intellect and imagination which, however great
its practical importance, could not take precedence over other equally valid
belief-systems. In our own day, when Idealism ceased to be fashionable,
philosophers have argued in a similar vein that science is no more than a
specialised activity which cannot, in the nature of the case, overturn the
view of mind sanctioned by ordinary language. Interactionism was kept alive
in the meantime by those few who took scientific materialism seriously
enough to try and refute it on its own grounds. They numbered among their
ranks philosophers, psychologists, physiologists and, of course, psychical
researchers, but, despite the eminence of some of the names one could cite,
theirs was a minority position which continued to bear a somewhat heretical
or, at least, deviant taint.
In what sense can it be said that science lends support to materialism? The
answer, I suggest, is twofold.
First, in the theory of evolution, materialism finds at least a plausible
cosmology; secondly, the science of neurophysiology presents us with some
striking demonstrations of the one-sided dependence of mind on brain.
From our point of view what was important in Darwinism was not so much that
it explained the origin of species with recourse to supernatural
intervention but that the one simple principle of the survival of the
fittest - perhaps the most fertile principle in the whole history of ideas -
could be applied quite generally to explain any semblance of design or
purpose in nature wherever there is random variation and natural selection.
Thus evolution is by no means restricted to phylogenesis. We talk of the
evolution of galaxies out of the primeval inter-stellar dust or the
evolution of organic and macro-molecules out of the elements just as
appositely as we talk of the evolution of intelligent life from simpler
organisms. In the face of this smooth cosmological sequence it is not easy
for the interactionist to gain a foothold. For, if inanimate nature evolved
of its own accord as a result of exclusively physio-chemical processes; if,
furthermore, the whole of the plant kingdom in all its prodigious diversity
evolved without the benefit of mind, as presumably did much of the animal
kingdom as well in its lower echelons, is it plausible to suppose, as the
interactionist must, that somewhere there is some definite point beyond
which further development would not have been possible had not mind
providentially supervened? Nor is it only in the phylogenetic sequence that
continuity must be breached in this unlikely way for the same question
arises with respect to the ontogenetic sequence of individual growth and
development.
Does mind cohere with matter at conception? At birth? At some point
intermediate between these two events? And, if the latter, is the union
automatic and invariable? Or, if not, does a mindless embryo fail to develop
and so perish?
One has only to pose such questions to realise how difficult it is to
reconcile an interactionist metaphysic with modern biological knowledge or
to appreciate why a latter day Darwinian, like Monod (1971), should champion
materialism. Moreover there exists no credible cosmology that would account
for the origins of mind or provide a reason for the intrusion of mind into a
mindless universe in the first instance, at best we have the various
mythical, religious or occult systems of a prescientific vintage to fall
back upon. In desperation some anti-materialists have opted for a
pan-psychism according to which mind
inheres in all matter everywhere even though its presence is somehow made
more manifest in the brain. However, while this restores a measure of
continuity, it is an extravagant solution with its implication that we are
potentially conscious in every atom of our body!
The argument from brain-science has perhaps an even more direct bearing on
our problem than the cosmological argument we have just considered. The
critical evidence in this connection comes from the study of brain damage,
whether due to injury, disease or deliberate surgical intervention. The
point here is that, if the interactionist is right to attribute some degree
of autonomy to mind, we would expect that we would be able to circumvent to
some extent such localised disruption, perhaps by using other parts of the
brain, whereas the evidence suggests, on the contrary, that, in the adult
brain at least, quite small lesions may suffice to cause the loss of vital
cognitive and motor functions or even, in some cases, drastic deterioration
in the personality of the afflicted individual. Even when, by an heroic
effort, the individual learns to adopt strategies to compensate for his
disabilities, as with Luria's patient, the deficit remains (Luria 1972).
Sadly we must admit that, in this context, the triumph of mind over matter
is, at best, no more than a figure of speech.
One special type of brain damage that has already provoked a certain amount
of philosophical controversy is that resulting from the so-called
split-brain operation, or commissurotomy, an operation that is carried out
only in certain very severe cases of epilepsy as a means of restricting its
scope. A patient whose corpus callosum has been severed is without the
normal physical means whereby information received at one cerebral
hemisphere is transferred to the other. Although such a person is able to
function more or less normally in daily life - so much so, indeed, that it
was many years before it was realised that the operation had these
consequences - when tested in special situations that can be contrived in
the laboratory it could be shown that the two hemispheres were functioning
autonomously and even, in certain circumstances, at cross-purposes with one
another!
Such a demonstration was possible because, with the cutting of the optic
chasm visual stimuli from one half of the visual field would go only to the
contralateral hemisphere while tactile stimuli from one side of the body
would go only to the ipsilateral hemisphere. As a result of the pioneer
investigations of Sperry in the 1960s and of the work of his successors we
now know that a set task can be successfully accomplished under the control
of one hemisphere alone without the other hemisphere evincing any sign of
knowing what has happened. Since it is the left hemisphere that contains the
speech centres this means, in particular, that the split-brain subject will
deny any knowledge of an object that has been presented exclusively to his
right hemisphere even when, by the appropriate response of his right hand,
he has just indicated his recognition of it! (Sperry 1965; Trevarthen 1974).
The philosophical problem which arises out of these facts is how we should
best describe such a paradoxical situation ? Are we to say that the
subject's mind, like his brain, has now been split in two yielding two
parallel streams of consciousness insulated from one another ? Or should we
say, for example, that the subject's mind is now associated exclusively with
his dominant left hemisphere leaving the mute right hemisphere to function
purely automatically and unconsciously ? Nagel (1971) has drawn attention to
paradoxical consequences of any attempt to interpret the situation in terms
of our familiar concept of the self. Zangwill (1976), on the other hand, has
voiced a strong plea for adopting our first suggestion and acknowledging
frankly the duplication of consciousness. At the same time he rebukes Eccles
for adopting our second suggestion stigmatising it as a desperate rear guard
bid to preserve the integrity of the soul. As Zanguill very aptly points
out, by all the criteria we normally apply when ascribing consciousness,
with the exception of speech, the activities associated with the right
hemisphere in the split-brain cases merit the attribution of consciousness
and to withhold it must incur the suspicion of special pleading. Moreover he
mentions at least one instance where the patient's entire left hemisphere
was removed and yet this patient did not thereafter appear to be any the
less of a conscious human being.
From the standpoint of the interactionist these discoveries are undeniably
disconcerting precisely because they bring out so dramatically the
dependence of mind on brain. Indeed long before commissurotomy was a
practical possibility its hypothetical implications were being discussed by
thinkers of rival persuasions (Zangwill 1974).
The dominant view, represented by Fashioner who believed in mind and matter
as parallel realities, was that the mind like the brain would become divided
and in course of time two distinct personalities would emerge depending on
which hemisphere was engaged. The minority view, represented by McDougall
who was a staunch interactionist, insisted that the unity of consciousness
and of the self would be preserved and that its preservation might afford
the most convincing proof for the existence of the soul! What, then are we
to say now that we know what transpires? We cannot say that either party has
been completely vindicated. Except under the highly artificial conditions of
the laboratory the personality of the split-brain patient survives intact.
What happens, it seems, is that the dominant or conversant left-hemisphere
takes charge and represents the individual to the outside world. At the same
time the subject's behaviour in the experimental situation is hard to
reconcile with a McDougall Ian or Cartesian unity of consciousness. However,
this unity had already been severely undermined by the increasing evidence
that came to light during the late 19th Century of dissociated states and
automatisms. Such bizarre phenomena as automatic writing, secondary,
alternating and even co-conscious personalities, fugue states, amnesic
episodes and suchlike - all of which were well known to McDougall who had to
do his best to grapple with them (Boden 1972 Chap 7) - raised questions
about the unity of mind no different in principle from those presented by
Sperry's evidence.
When the concept of the unconscious was still a novelty there was a division
of opinion which anticipates that between Zangwill and Eccles about what was
involved in unconscious activity. Some, like Zangwill, wanted to postulate a
secondary centre of consciousness to go with it which remained inaccessible
to the subject's primary consciousness. Others, Ã la Eccles, wished to deny
it the title of mental activity and regard it as the routine workings of the
cerebral machinery, no different in principle from the autonomic and reflex
activity of the nervous system that likewise takes place outside our
conscious awareness or control. The long Empiricist tradition in philosophy
which equated mind and consciousness made it seem inevitable that, when
confronted with clear evidence of intelligent or adaptive behaviour that was
not accessible to introspection, either one had to posit an extra centre of
awareness or else regard such behaviour as the activity of a sophisticated
natural computer. A third possibility, namely that mind might manifest
itself unconsciously, although a commonplace among psychical researchers,
was rarely entertained.
Even the depth psychologists who followed Freud, who were so preoccupied
with the unconscious, were, for the most part, content to adopt a
non-committal attitude regarding its ontological status provided they were
allowed complete freedom to develop their theories independently of current
physiological knowledge. We, however, who have liberated ours elves from the
positivist dogmas of Empiricism, should have no trouble acknowledging that
our unconscious actions may be no less under the control of mind than our
conscious behaviour.
Consciousness may well be the most distinctive sign of mentality but there
is no reason why we should regard them as synonymous. In the case of the
severed right hemisphere discussed by Zangwill I have no doubt that its
ativities were controlled by some sort of a mind but, whether that mind is
conscious or not and what relationship it hag to the mind which governs the
subject's dominant left hemisphere are questions about which I must profess
myself agnostic I will merely point out, before we leave the topic, that it
would be unwise to make so much of these rare anomalous cases, however
intriguing or important they may be, as to overlook the truly astonishing
degree of unity and coherence which obtains in our normal waking
consciousness. To quote Eccles: "Our brain is a democracy of ten thousand
million nerve cells, yet it provides us with a unified experience". (Eccles
1965 p.36).
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3
We have now covered at least some of the ground where materialism could be
expected to make most of the running. It is time to turn to a different
realm where the roles are reversed and it is materialism that is on the
defensive.
No philosopher, however partial to materialism, would deny that the way in
which we think about one another's behaviour in real or the way in which
this is reflected in all our ordinary discourse, is, in its presuppositions
and in its implications, overwhelmingly interactionist. For example, in real
life it is universally assumed that the fact that we consciously choose to
do something is causally relevant to the fact that we do it. To the
materialist, on the contrary, both our conscious choice and the subsequent
movement of our limbs are alike the effects of the particular brain state we
happen to be in at the time or, more specifically, perhaps, of the
particular distribution of electric charges in the cortex which determine
which nerve cells will fire and in what order. No amount of philosophical
double-talk (and there has been plenty) can disguise the fact that we have
here a massive contradiction which cries out for a resolution one way or the
other.
The demand is even more insistent in the case of our moral discourse. The
language of praise and blame, of pride and remorse, are meaningful only if
the ultimate responsibility for the action resides in the agent. If a
computer makes an error we do not hold it morally responsible for deceiving
us, yet it is hard to see why, if we are indeed just conscious automata, as
the materialist supposes, we should be held morally responsible for anything
that we do.
Even those philosophers, the so-called 'soft determinists' who maintain
that, in principle, there is no incompatibility between physical determinism
and the existence of free-will, now usually concede that, in practice, we
cannot at one and the same time conceive of ourselves as physical objects
and as moral agents. There is, it seems, a fundamental antagonism between
these two conceptions, to pass from one to the other demands a gestalt
switch of a kind that can be achieved only with exceptional mental agility.
The materialist can, of course, dismiss free-will as an illusion and moral
judgments as nonsense, as do the 'hard determinists', but, while many
philosophers from Spinoza onwards have adopted this course none, I think,
has successfully transferred it from the study to the market-place for the
simple reason that, in practice, it is virtually impossible to abstain from
moral judgment. Hence the hard determinist lays himself. open to the charge
of bad faith. None of this, of course, disproves materialism or determinism
because our moral intuitions may just be confused but it does expose the
strong counter-intuitive element in these doctrines.
What, in the end, makes materialism irretrievably implausible (though not
necessarily false!) is precisely that which makes our imaginary universe A'
so unbelievable. If the interactionist is right in supposing that the
presence of mind is necessary in order to produce mind-like behaviour, then
it is perfectly understandable why there should never be a state of affairs
like that represented by our universe A'. But, if, on the other hand, the
materialist is right and there is no reason at all why we ourselves should
be conscious rather than non-conscious, then there is nothing even
improbable about the situation that obtains in A'. Indeed, if we one day
encounter intelligent life elsewhere in the universe, where evolution may be
presumed to have taken a different course, we would have no grounds whatever
for assuming that these alien beings were sentient creatures like ourselves.
Worse still, the materialist is peculiarly vulnerable to solipsistic doubts
even when among his own kind.
The fluke which made our species conscious might, perhaps, have occurred
only in his own unique case, he might be a complete sport in that respect.
He cannot invoke the traditional analogical argument for rejecting
solipsism, namely that behavioural similarities between ourselves and others
justify the ascription of consciousness to them no less than to ourselves.
For, by his own admission, mind plays no part in the determination of
behaviour. The ultimate paradox of materialism is that the one feature of
the universe which alone gives meaning to all the rest is the one feature
which has to be declared redundant! Nothing can account for its emergence;
nothing follows from its existence.
Such considerations, however, are too abstract and metaphysical to count for
much with the materialist. For the truth is that the strength of materialism
has never been its logical cogency but rather its pragmatic or heuristic
value for science. By this I mean that if we adopt a materialist approach to
the phenomena of life or mind we open up the prospect of a reductive
explanation and even if this is never attained at any rate we have not upset
the unity of the sciences; nowhere are we forced to introduce some new
entity or principle that has no equivalent elsewhere in science. Now,
contrary to what some philosophers have written, reductive explanations are
by no means the only valid type of explanations but they are, undoubtedly,
the most powerful, perhaps for the same reason that physics is the most
powerful and universal of the sciences.
It is true that when we come to the behavioural sciences there is precious
little that admits of a reductive explanation but even if what we have is no
more than an abstract theoretical model it provides a challenge to the
neurophysiologist to explain how it might be embodied in the brain, thereby
completing the conceptual bridge linking behaviour at one end to physics at
the other.
It is now generally recognised that explanation in psychology is a two-stage
affair. This is best illustrated, I think, in the cognitive sphere.
We start by asking how is it possible for us to acquire skills or solve
problems; how, for example, do we contrive to recognise a melody? Ride a
bicycle? Put our thoughts into words etc.? At this stage someone comes along
with a theory. No reference is yet involved to the brain but if the theory
is at all rigorous it should be possible to program a computer to simulate
the activity in question. At this stage, which we might call the stage of
'theoretical psychology', our concern is much the same as that of the
cyberneticist or exponent of artificial intelligence. Only when further
evidence from the direction of brain-science is forthcoming is the second
stage complete when we are in a position to say that our theory tells us how
the brain actually operates in these circumstances as opposed merely to how
it might operate.
Lest we lose our sense of perspective at this point we should take note that
this second stage has not yet been completed even with the most basic
cognitive functions such as memory although, of course, there are scores of
abstract theories as to how particular kinds of remembering might be
mediated. It is no less important to recognise that all the dominant schools
of psychology are reductionist in the aforegoing sense. This applies equally
to those who now call themselves 'mentalists' or 'cognitive theorists' who
use concepts like 'internalised grammars' etc. as it does to the hardened
behaviourist who prefers to talk in terms of conditioning and to concentrate
on overt performance. Chomskyans and Skinnerians alike share the assumption
that the brain, as a physical system, possesses all the properties and
structures necessary to actualise their theoretical suppositions.
Granted that the whole enterprise of a scientific psychology makes sense, it
is hardly surprising that interactionism (often scornfully, if inaccurately,
referred to as the homunculus theory of mind) should be viewed as a gross
betrayal. For, if one starts from the assumption that how a person behaves
depends, in part at least, on his having a mind that is endowed with certain
unique properties and powers over and above those that belong to a
conceivable physical system such as the brain, then one tends to end up
explaining the behaviour in terms of those very powers of mind that one has
invented, on an ad hoc basis, precisely to account for the behaviour.
This type of circular explanation, notorious in psychology, takes us back to
the armchair theorists and faculty psychologists of the 19th Century. The
only escape from this is to have an independent theory of mind, analogous to
physics as a theory of matter, but this has so far eluded us, mind as such
remains the densest of mysteries. The history of psychology has been
largely, therefore, a revolt against interactionism which was identified
with common sense psychology.
Fear of the homunculus has kept academic psychology firmly tied to the apron
strings of materialism. Perhaps the one important school of psychology - if
indeed one can describe it as a school - which acknowledged the autonomy of
mind was Functionalism which flourished around the turn of the century. Its
most illustrious spokesman, William James, took issue with the
epiphenomenalism of Wundtian psychology or Kraepelinian psychiatry and
argued that mind, like everything else in nature, must have a biological
function. But his championship was not enough to turn the tide.
We have, it seems, reached a stalemate. Materialism, we may con cede, is
more in tune with scientific thinking and more conducive to scientific
research but, in all that concerns our humanity, there seemed little doubt
that interactionism makes better sense. Unless, therefore, some fresh
arguments were to make materialism intuitively more plausible or,
alternatively, unless fresh evidence were forthcoming that would make
interactionism scientifically more acceptable, which of the two command our
allegiance may depend on whether our outlook is more influenced by
scientific or humanistic considerations. While it is clearly impossible to
anticipate what ingenious new arguments may yet be cast into the arena,
there is already a body of evidence which, if it carried more weight, would
seriously weaken the scientific plausibility of materialism. For there is
One empirical implication which we have not so far mentioned which does
distinguish between the two opposed positions. If mind is something distinct
from the brain with which it normally interacts, then it is at least
conceivable that it could, in certain circumstances, interact with other
physical objects or systems. If, on the contrary, there is no distinction
between mind and brain, inasmuch as mental processes are just a function of
brain processes, then, clearly it makes nonsense to talk of the mind
functioning independently of the brain.
Now it so happens that there is already what one can only describe as a vast
amount of evidence which, if taken at its face value, would suggest that
mind interacts on occasion, with external physical objects. I refer, of
course, to parapsychology (Beloff 1974, 1977).
Although, in our present state of ignorance, parapsychology has to be
defined in purely negative terms, i.e. as the study of those phenomena that
cannot be explained in terms of accepted scientific principles, that is to
say in materialist terms, conceptually, it could be thought of as concerned
with those powers of mind that are irreducibly mental or non-physical.
According to this positive conception parapsychology could be defined as
that part of psychology which deals with the mind-matter interface. At a
more concrete operational level parapsychology is concerned with two
particular phenomena:
(a) where an organism obtains information about events remote in space
and/or time without such information being conveyed via any known physical
channels, as is the case with normal perception
and:
(
where an organism influences events remote in space and/or time againwithout such an effect being transmitted via any known physical channels as
is the case with normal motor activity.
(a) is known technically as ESP and (
is known technically as PK and,collectively, the phenomena are known technically as PSI.
Although, as I have said, the evidence for PSI is extensive, much of it is
of an inferior quality, some of it is definitely suspect and none of it is
decisive. It is not decisive for one very good reason, there is as yet no
PSI effect that can be demonstrated on demand.
Science cannot afford to relax the rule which demands that any new claim
must be confirmable by those competent to test it. Whether PSI phenomena are
peculiarly elusive or non-existent or whether we simply do not yet know
enough about the conditions under which they occur to ensure their
reproducibility, the fact remains that they cannot qualify as yet for
inclusion into the body of accepted scientific knowledge. Nevertheless, when
this has been said, the fact remains that one would need to be either very
ignorant or very prejudiced or, better still, both to argue that the
evidence is so derisory that it can safely be ignored in this context.
What the materialist must ask, therefore, is, assuming that the evidence is
valid, does it necessitate an interactionist interpretation or could it in
the last resort be reconciled with materialism? It is true that nothing so
far known to brain-science would have led us to suspect that the brain, as a
physical system, could communicate with objects remote in space, let alone
in time, nevertheless one can never say that one is never in a position to
say that all the physical possibilities have been exhaustively considered.
Hence, however tempting it may be to describe PSI phenomena in terms of
mind-matter interactions, alternative conceptualisations cannot be excluded.
Two developments within parapsychology would, I believe, upset the case for
claiming this field as affording empirical grounds for the interactionist
thesis. If it were possible to demonstrate ESP or PK using only computers or
other appropriate artifacts or using only living tissue in vitro or even
plants in lieu of a human or animal subject, in other words systems to which
we would not normally attribute a mind, there would be little temptation
left to think of such phenomena as a manifestation of mind. The state would
be set for their eventual incorporation into an extended and revised physics
and materialism and, with it, the unity of science would be vindicated. But
if this does not happen and if, nevertheless, parapsychological claims
become increasingly hard to ignore, then the case for interactionism would
become more than just a metaphysical choice.
To avoid misunderstanding at this point, it should not be thought that the
interactionist will have to propose certain paraphysical forces or energies
to make up for the missing physical connections, as one often finds in the
more naive parapsychological theories. It is much more plausible to suppose
that the way in which mind and matter interact is different in kind from the
way matter interacts with matter. There is a strong suggestion, which I
cannot enlarge upon here, that, in PK for example, the effect is produced
not by feeding additional energy into the target-system but rather by
feeding in pure information so as to alter the probabilities of events at
the microphysical level while leaving the overall energy of the system
invariant. There is likewise a strong suggestion that PSI processes may be
irreducibly teleological in their mode of action by which I mean that the
end somehow dictates the specific means which bring about its fulfilment.
But this takes us into the realm of speculation, critics might even say into
the realm of magic.
For the present, and in all probability for a very long time to come, it
must remain a matter of philosophical opinion whether mind is for anything,
and, if so, what precisely it is for, or whether mind is merely an aspect of
matter which, by the grace of nature as it were, happens to be associated
with the workings of our brain. Psychology as we have known it so far could
teach us only about the behaviour and experience of the unified
psychophysical organism; it might be, however, that the mind-science of
tomorrow, when paranormal as well as normal phenomena have been taken into
account, will be able to return an unequivocal answer to the question of why
we have minds at all.