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3.
Kripke’s Argument and the Zombie Argument
The Strategy of Materialism:
Denying or Ignoring
the Mind as Subjectivity
Materialistic theories of mind have many advantages and only one
drawback: they are not theories of mind. John Searle aptly remarked that the
title of the main work of the famous modern philosopher-materialist
D. Dennett, “Consciousness Explained”, does not correspond to its content:
“Consciousness Denied” would be more appropriate.[1]
In effect, the situation is similar with all materialistic theories of mind.
They are all “theories which deny what they cannot explain”[2];
they overlook, ignore, or substitute it with something other.
What materialistic theories of mind cannot explain is the very existence
of personal realms of subjectivity, which we call “minds”, the existence of a
subject-carrier of subjective experiences and awareness – the mental self. Most
often, materialistic theories do not deny the mind openly but proceed as if to
explain the mind is nothing more than to explain its behavioural manifestations.
The mind itself, as states-processes of subjective experiencing,
thinking, and awareness, is merely ignored.
Materialistic theories
either 1) regard the mind only as a system of
control of behaviour, ignoring or denying the mind as a realm of subjectivity,
or 2) postulate the identity of subjective
experiences with physical processes in the brain.
In the first case, materialists openly deny or ignore the mind. In the
second case, they postulate the identity of things that have no common
properties:
– on the one hand, physical processes – movements (changes of spatial
locations with time) and interactions (influences on the character of
movements) between physical bodies (or between physical bodies and space) in
which there is nothing subjective and which occur purely
automatically according to physical laws,
– on the other hand, experiences and awareness
as subjective states-processes
that are not characterizable in terms of spatial locations.
Such identification of incomparables is also a form of denial (ignoring)
of the mind as a personal realm of
subjectivity. Supporters of this theory deny or fail to notice that besides
movements and interactions of physical bodies and space (all that is encompassed
by the concept of the physical), in which there is nothing subjective
and which occur purely automatically according to physical laws, something
else takes place – subjective experiences and awareness. This something
besides the physical is the mind.
Regarding the problem of the nature of the mind, the key concepts are
those of subjective experiences and awareness and of the subject-bearer of
these experiences and awareness, the self. The concept of subjective
experiences encompasses not only what is often called spiritual experiences
(emotions and feelings, such as happiness, grief, love, and hatred) but also
what is often called physical (bodily) sensations as they are experienced
subjectively – how it (pain,
heat, cold, red or green colour, etc.)
feels. Imagine a colour-blind (or deaf) person who wants to know how
it feels (what it is like) to have a visual sensation of green colour (or
an auditory sensation). This is surely not the same as a colour-blind (or deaf)
person who tries to learn what physical processes in the brain allow people to
have visual sensations of colours (or auditory sensations)!
Materialistic theories of mind can describe physical processes in the
human body and human behaviours associated with different subjective (mental) states,
but this leaves out these states themselves – as subjective (mental) states, as
something experienced subjectively – and our selves as subjects who experience
them and are aware of them (not just as bodies in which various physical
processes – movements and interactions of parts and particles – occur
automatically in accordance with physical laws).
No existing or possible description of
whatever physical processes – that is, of movements and interactions
(influences on movements) of some physical objects (such as molecules, atoms,
electrons, etc.) according to physical laws – will contain even the smallest
hint of subjective experiences and the awareness thereof.[3]
Kripke’s
Argument
Usually, a transition from a common folk concept to scientific understanding
is carried out through abstraction from the phenomenal component of the
common folk concept. For example, the concept of heat is understood at the
common folk level through the sensation of warmth; heat is something that
causes a subjective experience of “how it feels when it is warm”; water is
something identifiable through visual (transparent, gleaming in the sun, etc.),
tactile (wet), and gustatory sensations and observable properties of movements
(liquid). Understanding at the scientific level is discovering that “something”
that “stands behind” these subjective perceptions – what it is “in itself”,
irrespective of our perceptions. Thus, we learn that the thing that “stands
behind” (causes) our sensation of warmth is “in itself” the kinetic energy of
the movements of molecules, that the thing that “stands behind” (causes) our
various perceptions united by the word “water” is “in itself” an aggregate of
molecules with a certain atomic structure and certain properties (H2O),
etc. Is it possible to explain mental states (states of the mind) in the same
way?
Saul Kripke offered an argument that shows that it is impossible to do
so. The argument is formulated in rather abstruse, technical terms; what
follows is my free “translation”-interpretation of it.
Why is it impossible for mental states to be
explained in the same way in which warmth, water, and other similar natural
phenomena are explained – through abstraction from “the phenomenal component”
and by discovering what “stands behind” (causes) it?
The reason is simple: it is exactly “the phenomenal component” that
needs explanation in this case. It is impossible to explain a phenomenal state
through abstracting from its “phenomenal component” because then nothing would
remain. It would merely be ignoring the phenomenal state, substituting it with
something other instead of explaining it.
In the case of warmth, water, etc., we are interested in something
outside the mind that influences the mind (with mediation of the nervous
system and the brain) in such a way that it evokes specific subjective
sensations, awareness, phenomenal states. In the case of pain, pleasure,
thinking, and desires, the situation is entirely different: we are interested
exactly in subjective sensations,
awareness, phenomenal states as such
“things” that belong to the mind. Accordingly, in cases of the first
type, we can and need to abstract from the mind, but in cases of the second
type, such an abstraction would mean overlooking exactly the “thing” that we
need to explain and explaining instead something other.
Let us take, for example, the sensation of pain. “Pain”, in the ordinary
(common folk) sense of the word, is the subjective experience of
how-it-feels-when-it-pains. If we try to abstract from “the phenomenal
component” and replace the common folk concept of pain with a “scientific”
concept of pain as something that “stands behind” the experience of pain, then
we can say that pain is such and such physical (biochemical) processes in the
nervous system and the brain. However, it would not be an explanation of pain
in the ordinary (common folk) sense of the word “pain”; it would only be
changing the meaning of the word. Of course, we can agree to use the word
“pain” in the sense “such and such physical (biochemical) processes in the
nervous system and the brain”, but this will not provide us with any
explanation of the existence of the experience of how-it-feels-when-it-pains
(whatever name you give to it). Instead of an explanation, it would be just
meaning jugglery – the substitution of what had to be explained with something
other – slipping from something unexplainable by physical (material) processes
to some other thing that is easily explainable by them.
Variations on the Theme: the Body and
the Self
From the points of view of the main competing theories at issue, the
relation between the human self (as a mental subject) and the body is as
follows:
1) Materialism. Each of us is a (physical) body. I am some (physical) body, and you are some
other (physical) body.
2) Dualism-interactionism. Each of us has a (physical) body. In particular, there is you and there is
your body (I and my body), and they interact in a complex way.
In any case, there is a body (in the first
case, it is your body, and in the second, it is a body that is you). In this
body, there occurs a huge multitude of various physical movements (changes of
spatial locations) of its parts and particles (smaller physical bodies) –
cells, molecules, atoms, etc. – and a huge multitude of physical interactions
(attractions and repulsions) that influence these movements and occur purely
automatically according to physical laws. This is all that takes place in your
body. But where are your subjective sensations, emotions, desires, and
thinking? Materialists say that these are nothing but physical processes in a
specific part of your body, the brain. Is this possible?
Let us consider the simplest example. If there are experiences that are
states of the body, then surely pain should be one of them. What experience is
more bodily? However, on better thought, it is easy to understand that pain and
all other so-called “bodily” experiences (for example, visual or auditory
sensations) do not belong to the body, to
physical reality; they are nonphysical. If they seem bodily, this means
only that of all subjective experiences, they are the most directly and obviously connected with the body.
So, let us think of pain. Perhaps it will not be superfluous to remind that pain is not an anatomic theory of
pain. Pain is how-it-feels (to me or to you) when it pains, neither more nor
less. Pain (as well as any other sensation or emotion) is some specific (your
or my) subjective experience. However, in a purely physical
(materialistic) horizon, there is no place for this pain as a subjective
experience (for what we express by the phrase “it pains”), as well as for
all other sensations and emotions.
Imagine that my (your) hand has got on fire and got burnt. What does occur in such a situation?
There is a huge multitude of physical processes: movements of cells, molecules
and atoms that propagate through the chain of nerve cells toward the brain,
within the neural network of the brain, and finally, from the brain to the
muscular system; as a result, the hand withdraws from the fire. From the point
of view of materialism, all this occurs purely automatically according to
physics laws; nothing more happens. But is this really so?
Every human being knows from personal experience that something more
happens, viz.: that one feels
pain, has a subjective experience of pain. Besides all physical
processes, there is the feeling
(sensation) itself – how it feels when it pains. Let me rewrite the same in the reverse order: the feeling (sensation)
of pain is something that is there besides
all physical movements and automatic interactions. The same is true
for all subjective experiences. They all are something in addition to the
physical processes in the body (brain) – that is, something nonphysical. Hence,
materialism is false.
According to dualism, besides your body, there
is you (your self) as a subject of experiences and other mental states. In the
case of pain, besides the physical (automatic) interactions and movements as
described above, there is also your feeling, your subjective experience of
pain. The former (physical movements) is
closely connected with the latter (the feeling as a
subjective experience), but the former is
not the latter. The feeling is something besides, in addition to those
physical processes, although it is caused
by them. Your feelings are your subjective states that are evoked by some physical processes in your body, but they are not some physical processes in your
body.
As another illustration, imagine that you write
an essay or solve a creative task. When you do this, many different physical
processes (interactions and movements of particles) occur within your body.
From the point of view of materialism, that is all there is: brain cells
(neurons) automatically interact, according to the laws of physics and
chemistry, with one another (their electric states change and certain chemical
substances are transmitted) and with the cells of the muscles of your hand; as
a result, the hand moves a pencil on paper and leaves some signs on it. This
description misses something that everyone knows from personal experience –
what constitutes our experience – our personal realm of subjectivity, mind,
consciousness – your thinking, understanding, guesses, doubts (mental
activity), and your subjective experiences of these processes.
******
The human body is nothing but a very complex organized aggregate of a
huge multitude of molecules, atoms, and other microparticles. Atoms and
molecules do not feel and are not aware of anything, and their arrangement into
a hugely complex physical system (a human body) changes nothing per se. However they are arranged, they
will remain nothing but a hugely complex aggregation of atoms and molecules
that move and interact purely automatically according to physical laws. No
matter how long we study and how we describe these movements and interactions,
all that we can know in this way are physical movements and interactions of
physical bodies that occur purely automatically. In all these, there is no hint
of subjective experiences and awareness. The human self as a subject of
experiences and awareness remains missing.
If materialism is true, then there is nothing
besides various parts (particles) of the body and their movements (changes in
their spatial locations), which are automatically determined by the influences
of other parts (particles) of the body and of external physical processes
acting on external parts (particles) of the body according to physical laws. If so, the subjective is utterly
superfluous. If the physical is not influenced
by anything nonphysical, then all physical processes occur automatically in accordance with
physical laws, quite independently of any subjective experiences and awareness.
Whether or not there are subjective experiences and awareness cannot affect the
physical laws and the physical interactions and movements determined by these
laws. All such movements and
interactions would occur exactly as they do occur if there were no subjective
experiences and awareness – if we all felt nothing and were aware of nothing, that is, if we as mental subjects
did not exist.
If subjective experiences exist nevertheless
(and you know that they do, at least with regard to your own subjective
experiences), then they are something besides, or in addition
to, physical processes, although very strongly dependent on these
processes.
The conclusion. Materialism is mistaken: besides physical
objects and processes,
there are subjective experiences (sensations, emotions, and awareness) and mental
activity (thinking and will), and there is the self as their subject or
experiencer. Subjective experiences do not exist on their own, without a
subject who experiences them – the subject we designate by the word “self” or
“I”. I feel, experience my life emotionally, think, and will.
Here, the word “I” designates not my body but myself. I, my (or
your) self is a pure subject of feeling, experience, thinking,
and will. My body as such, as a physical system, does not feel. All
there is to my body are great many various physical processes – physical
interactions and movements of various parts and particles. However, there is an
interaction between myself and my body. The physical processes in my body evoke
in me various feelings, my thinking influences my will, and my will causes some
physical processes in my brain and, through them, external movements
(behaviour) of my body.
******
The falsity of materialism can be explained by analyzing the content of the concept of the physical
(material). This content is reducible to spatial locations and movements
(changes of spatial locations) of physical bodies, interactions that affect the
velocities and directions of such movements, and laws and properties that
mediate such interactions and determine the character of movements. (For a more
detailed discussion, see Section 1.)
Accordingly,
all that is explainable (understandable) in terms of the physical (material)
are various movements of physical bodies (changes of their spatial locations),
and nothing more. The realm of the physical is confined to these movements and
mediating laws and properties, where the concepts of laws and properties
designate various regularities in spatial movements or in changes of
regularities in spatial movements – regularities that fit with the movements
already observed and allow predicting successfully the movements that will be
observed. It is logically impossible to get beyond these precincts
while remaining within the realm of the physical (material). But everything
subjective (our sensations, emotions, and thoughts – how we experience them
and are aware of them) is outside these precincts. The contents of the concepts
of pain, pleasure, thought, etc. are entirely independent of physical bodies,
structures, movements, and the regularities (laws) discoverable in these
movements. All mental (phenomenal, subjective) concepts have an independent
source – our self-consciousness, introspection. We know about our
sensations, emotions, and thoughts directly because we feel-experience them and are aware of them subjectively; we do not
presume-conjecture their existence (as we presume-conjecture the existence of
various physical laws and properties or of physical microparticles that are not
directly observable) to account for observed patterns of movements of physical
bodies and to predict such movements.
This means that the concept of the physical (material) does not cover
all reality. Namely, it does not cover what is the most important for every
person – the human self as an entity that
subjectively experiences and is aware of the world and her own sensations,
emotions, and thoughts.
The Zombie Argument
If
all that occurs in the human body (brain) are only automatic interactions and
movements of particles (molecules, atoms, ions, electrons, etc.) according to
physical laws, all these processes would occur exactly as they do – according
to the same physical laws, without a slightest change in any physical property
– if there were no subjective experiences at all. From the outside, everything would
look exactly the same: these humanlike bodies would behave in exactly the same
way, although without any feelings and awareness (in the sense of feelings and
awareness as subjective experiences).
We can imagine a phenomenal zombie – a humanlike body that is
physically and behaviourally exactly identical with a living human body but subjectively experiences absolutely nothing
and has no subjective awareness whatsoever. It behaves exactly in the same way as the human body (in
the corresponding situations, it carries out the corresponding movements of the
corresponding parts of the body); it consists of the same atoms and molecules
that are ordered in exactly the same spatial structures and make exactly the
same motions. However, all its internal and external movements occur purely
automatically as a result of physical interactions, without any subjective experiences and awareness. After all, there
is nothing in physical interactions that would presuppose subjective
experiences and awareness; they are carried out automatically according to
physical laws. (This, in fact, is exactly what distinguishes physical processes
from the mind.)
Admittedly, the possibility of the real
existence of such zombies seems rather implausible. However, this is so only
because you know from your own personal experience how much your behaviour
depends on your mind (subjective experiences and thinking) and how much your
bodily processes affect your mind. However, from the point of view of
materialism, all this is but an illusion – a very queer, noone’s
illusion. All there really is are physical interactions of various parts and
particles of our bodies that occur automatically according to physical laws –
in the same way as in the case of the zombie. This means that we are such zombies.
However, we know that we are not. Every person
(even those materialists who deny it) knows that besides such
events as movements of various parts of her body and interactions and movements
of atoms and molecules within her body that occur automatically according to
physical laws, there is yet something: she subjectively feels pain,
heat, cold, pleasure, grief, love, hatred; she desires something;
she thinks of something; and she is subjectively aware of
what she feels, desires, and thinks. She exists not just as a
physical body but as a being who subjectively feels, wills, thinks and is
aware.
The Syllogistics of the Zombie
Argument
The zombie argument can be formulated as a
syllogism:
1) The existence of phenomenal zombies is
logically possible (the concept of a phenomenal zombie is logically consistent,
noncontradictory).
2) The phenomenal zombie physically does not differ from the
human being.
3) The human being differs from the phenomenal zombie in having the phenomenal
mind (consciousness, subjectivity).
Hence, what constitutes the
difference between the human being and the phenomenal zombie – the phenomenal
mind, consciousness, subjectivity – is nonphysical.
(The same can be reformulated in terms of logically
possible worlds by means of a simple replacement: instead of “the human being”
– “our world”, instead of “the phenomenal zombie” – “the world of phenomenal
zombies”).
However, in this form, the argument can raise doubts: whether it is
correct to compare (differs – does not differ) something really existent (the
human being) with something logically possible but most likely nonexistent (the
phenomenal zombie)? This doubt can be removed by reformulating the zombie
argument as an argument about the contents of concepts:
1) The physical contents of the concepts of a phenomenal zombie
and a human being are identical.
2) The full contents of the concepts of a phenomenal zombie and
a human being are not identical in that the concept of a human being, unlike
the concept of a phenomenal zombie, presupposes having the phenomenal mind
(consciousness, subjectivity).
Hence, the phenomenal mind
(consciousness, subjectivity), if it exists, is nonphysical.
From
this, we proceed to the refutation of materialism:
1) The phenomenal mind (consciousness, subjectivity), if it exists, is
nonphysical.
2) The phenomenal mind (consciousness, subjectivity) exists.
3) Materialism contends that nothing nonphysical exists.
Hence,
materialism is false.
See also the formulation given by D. Chalmers – I
quote it at the very end of Section 6.
The Three “Stimulus-Reaction” Models:
Dualism-Interactionism,
Materialism, and Epiphenomenalism
When we talk about sensations, emotions, thinking, desires and behaviour
of a person, we need to distinguish the following:
1) physical processes in the nervous system and the brain of the person,
which the materialist believes to be sensations, emotions, thinking, and
desires, whereas the dualist considers them as partially responsible for
sensations, emotions, thinking, and desires and for the corresponding behaviour
– let us designate them as signal-regulative neurophysical processes
(SRNP);
2) sensations, emotions, thinking, and desires as subjective (mental) experiences and activity (SMEA);
3) behaviour that is observable from the outside (B).
From the point of view of
dualism-interactionism, subjective experiences and mental activity interact
with signal-regulative neurophysical processes and influence behaviour through
this interaction. The general scheme looks as follows:
or
From the point of view of materialism, the signal-regulative
neurophysical processes directly cause behaviour:
or
However, this leaves no place for subjective experiences (e.g., pain as
not merely a chain of physical movements that belongs to SRNP but as what
people mean when they say that it pains – pain how it feels. Any possible description of physical processes will
be merely a description of the movements of various physical particles, with no
hint to subjective experiences. Particles just move and influence one another’s
movements (their velocity and direction) purely automatically according to
physical laws. Subjective experiences are outside any possible description
limited to the physical processes. As from the point of view of materialism,
nothing exists besides physical processes, this means that all that ordinary
people call (and always called) sensations, emotions, thinking, and desires is
merely ignored, overlooked in the materialistic horizon. There is no place for
them in a consistently materialistic scheme of the world. (Of course,
materialists can use the words “sensation”, “emotion”, “thinking”, etc. in
quite a different sense; it is like calling a cat “a dog”.) In the
materialistic world, there are no sensations, emotions, desires, and thoughts
as something subjectively experienced and subjectively known; there are no
subjective experiences and subjective awareness; they do not exist at all.
Imagine a world inhabited with phenomenal zombies –
this
is the only consistently materialistic picture of a world that is physically
identical with our world. However, the world, as depicted in this picture, is not our world.
Besides materialism and interactionism, there is a third alternative,
which is called epiphenomenalism or weak dualism. Its
adherents admit that the mind (subjective experiences) exists and is something
besides physical structures and processes; however, at the same time, they
adhere to the theory of the causal closure of the physical (that physical
events are caused only by other physical events). It means that, although
subjective experiences exist, they do not influence anything in the physical
world. In particular, they do not influence the behaviour of human beings. All
motions of the human body (and within the human body) are determined by
physical interactions according to physical laws:
or
This alternative is hardly more acceptable than
materialism. If our sensations, emotions, thoughts, and desires do not
influence our behaviour, they lose almost all their significance. For example,
it turns out that I cannot do anything because
I want to do it; everything that I do, I do automatically, and the
corresponding desire arises also automatically as a by-effect. If I write this
text, it is not because I am interested in a certain problem and have some
thoughts that I judge worthy of writing but because the fingers of my right
hand move automatically as a result of a very complex series of automatic
interactions (most of which occur in my brain) according to physical laws,
whereas my thoughts and interests merely arise in parallel and have no influence
whatsoever. Also, I have no reasons to believe that other people have minds,
for they would behave exactly as they do if they did not have this
“epiphenomenon”.
Interactionism
and the Logical Possibility of Phenomenal Zombies
John Perry[4]
advanced the objection against the zombie argument that it implicitly assumes
the truth of epiphenomenalism – anticipates the solution of the controversial
point (begs the question)[5].
Phenomenal zombies are possible only if epiphenomenalism is true, that is, only
if the following two conditions are satisfied: 1) the mind is nonphysical and
2) the mind does not influence physical processes in any way. However, the
truth of epiphenomenalism is exactly what is at issue in the discussion.
David
Chalmers disagrees:
1) “...Whatever the merits of the zombie argument, however, it does not
beg the question.”
2) “…the zombie argument is not just an argument for epiphenomenalism” –
it is consistent with interactionism as well.
To support these statements, Chalmers advanced arguments
that do not seem felicitous to me. In what follows, I advance different
arguments and explanations.
1. The
zombie argument is not begging the question against materialism, because it
is based entirely on premises that are
accepted by all varieties of materialism as well as by epiphenomenalism. (I
regard panpsychism not as a variety of materialism but as a separate direction.
See, in particular, the subsections about panpsychism and russellianism in
sections 9 and 11 of Book 2.) The premises are as follows:
(1) The general concept of (micro-)physical facts as
facts about purely automatic (according to physical laws) movements and
interactions of physical entities (microparticles, fields, and waves) that are
not subjects capable of subjective experiences and awareness. (If this general
concept is not accepted, the view is not materialism but panpsychism.)
(2) The postulate of the causal closure of physical
reality, according to which physical processes (in particular, those in the human
brain) can be influenced only by physical factors (cannot be influenced by
something nonphysical).
The logical possibility of phenomenal zombies follows
from these two premises by the way of the following reasoning:
(1+) The sense of the concept of the physical facts,
as explicated above (in (1)), is such that from any possible facts (from any
possible set of facts) of this sort, the presence of phenomenal mental states –
something subjective – does not logically follow. Thus, no possible combination
of such facts makes the presence of phenomenal mind logically necessary. In
other words, given any possible
combination of physical facts, the absence of phenomenal mind is logically
possible.
(2+) Since, according to the assumption (2), the
processes in the human body (brain) are influenced only by physical factors and
since, according to the concept of phenomenal zombies, in their case, there are
all the same physical factors, so there is nothing to make the dynamics of
physical processes in the body (brain) of a zombie different from the dynamics
of physical processes in the body of a human being.
Hence it follows that a humanlike body with the same
physical processes inside as those in the body of a human being, and behaving
exactly as the human being, but without phenomenal mind – that is,
a phenomenal zombie – is logically possible.
Let us notice that the considerations (1+) are on
their own sufficient to refute materialism, and in fact, the zombie argument is
just their spectacular representation. The logical possibility of phenomenal
zombies (on the assumption of the causal closure of physical reality) follows
from the fact that there is no logical inference from the physical facts (1) to
facts about phenomenal mental states (something subjective) – that is, there is
a logical gap between these two kinds of facts that cannot, in principle, be
filled by any possible physical facts (1). This position is well-known in the
modern philosophy of mind under the name of “the explanatory gap”. Many
philosophers-materialists acknowledge the existence of the gap but (following
the example of J. Levine, the author of the already classical book about
the gap[6])
construe it as epistemic (telling about our knowledge and capacities for
understanding), not ontological (telling about reality). I think that such an
interpretation is unsatisfactory: as there is a logical gap that cannot be filled by any physical facts (1), as no possible physical facts (1) logically
necessitate any phenomenal mental facts (in other words, any physical facts are logically possible
without any mental facts), this means that the phenomenal mental facts are not some physical facts (or their
functional aspect) but are something in addition to the physical facts.
To sustain materialism in the face of the logical gap
between the physical and mental facts, materialists (especially adherents of
the direction known as “the identity theory”) merely postulate that mental
states are identical with some physical states (processes) in the brain. The
psychophysical identities so postulated serve as br³dg³ng pr³nc³ples to get over the gap between the physical and
the mental. However, if special principles are needed to bridge the gap between
the physical and the mental, what is their logical and ontological status?
These principles are not logical
relations of inference (implication) from physical to mental facts; on the
contrary, they are introduced exactly because there are no such logical
relations. If so, these principles should be facts of how the world is arranged.
However, they are not physical facts in the above-explicated sense (1)
– their character is entirely different. Thus, these bridging principles turn
out to be some special facts that supplement the physical facts proper (1) and
connect them with mental facts. If so, these principles are not identities at
all but special physic-mental laws of nature, such that in their virtue,
physical states cause or “produce” nonphysical mental states.[7]
However, this is exactly what epiphenomenalism tells!
2. The zombie argument is not an argument against interactionism
Chalmers suggests that “the possibility of zombies is
compatible with non-epiphenomenalist dualism”: “an interactionist dualist can
accept the possibility of zombies, by accepting the possibility of physically
identical worlds in which physical causal gaps (those filled in the actual
world by mental processes) go unfilled, or are filled by something other than
mental processes.”[8]
Against this suggestion, one can object that if the
causal gaps (that are filled in human beings by mental processes) are filled in
zombies by something else, then the zombies are not of the kind stipulated by the initial conditions of the zombie
argument. According to these conditions, zombies should be, first, purely
physical (which excludes the possibility of filling the causal gaps by
something nonphysical) and, second, exactly the same as human bodies in all
physical respects (which excludes the possibility of filling the causal gaps by
some additional physical factors). As for the possibility that the causal gaps
in zombies go unfilled, this would violate physical laws; however, it is
arguable that the very meanings of such concepts as “mass”, “electrical
charge”, etc. (designating physical properties) are inseparable from the
corresponding physical laws; therefore, violations of these laws can be
considered as violations of the demand that the zombies should have all the
same physical properties as human bodies. To obviate this objection, one can
try the supposition that in human beings, the mind influences processes in the
brain on the quantum-mechanical level; if so, a phenomenal zombie is logically
possible such that in its brain, owing to
a hugely improbable coincidence of quantum-mechanical chances, all physical
processes happen to be exactly the same as in the brain of a human being.
However, the logical possibility of such phenomenal zombies depends on whether
the human mind in fact influences the brain at the quantum-mechanical level, of
which we do not know.
Perhaps, these problems are not critical. In
particular, one may point out that the difference between the initial version
of phenomenal zombies and “modified” phenomenal zombies with the causal gaps
(that in human beings are filled by mental processes) filled by something else
is not essential in the context of the zombie argument.[9]
After all, even if, in the case of modified zombies, there are some additional – physical or nonphysical – factors that are absent in the case of
human beings, the zombies are not lacking
any of those physical and functional states and processes that occur in human
bodies; nevertheless, they have no mind.
However, I think that this way of making the logical
possibility of phenomenal zombies consistent with interactionism is irrelevant
– just because such consistency is not
needed.
Taking into account what was said above about the
premises on which the zombie argument is based, if it was advanced as an argument against interactionism, there
would be all reasons to decline it as begging the question – because the
premise (2) about the causal closure of physical reality is exactly what
interactionism denies.
However, because the zombie argument is advanced not
as an argument against interactionism but as an argument against materialism
(which accepts the thesis about the causal closure of physical reality), it
does not beg the question and leaves open the question of whether physical
reality is indeed causally closed. Thus, the zombie argument refutes
materialism, but it does not affect interactionism at all.
Really, the logical possibility of phenomenal zombies
follows from the assumption that all physical processes in the human body are
effects of only physical causes
(other physical processes in the human body and external physical processes
that influence the body). In all these processes, there is nothing besides
automatic interactions and movements (according to physical laws) of the
elements (molecules, atoms, ions, electrons, etc.), none of which is a mental
subject capable of subjective experiencing and awareness, and automatic changes
of magnitudes of physical fields, which are not such subjects either. That is,
in all these processes, there is nothing subjective, and there is no mental
subject (self). If so, all these processes could occur without any subjective
experiences, and we would have, instead of a conscious human being, its zombie
twin. Thus, if the causal closure of physical reality
is assumed, there is nothing to
logically exclude the possibility of phenomenal zombies – phenomenal zombies
are logically possible.
Otherwise, if (as interactionism contends) physical
reality is not completely causally closed, and the brain processes in control
of behaviour are causally influenced by nonphysical mental states (our
sensations, emotions, thoughts, desires, and will), then phenomenal zombies –
at least, in their initial “purely physical” version and without extremely
improbable coincidence of chances – are logically impossible in virtue of the
simple reason that physical processes in their brain are not influenced by
those mental factors that (on the interactionist assumption) influence physical
processes in the human brain; accordingly, their dynamics should differ.
Thus, the zombie argument “works” only in the context
of the assumption, shared by materialism and epiphenomenalism, of the causal
closure of physical reality. It shows that if
physical reality is causally closed, phenomenal zombies are logically
possible, which means that materialism is false and epiphenomenalism is true.
However, it leaves open the question of whether
physical reality is indeed causally closed and, thus, which of the two
dualist options – epiphenomenalism or interactionism
– is true.
An interactionist, as well as an epiphenomenalist, can
use the zombie argument to show the
untenability of materialism proceeding from the premises accepted by
materialists; however, the interactionist need not accept these premises
herself.
Let us notice that the logical possibility of phenomenal zombies refutes
materialism not single-handedly but in conjunction with a certain fact about
the actual world, namely: in the
world, there are beings that have the mind, subjectivity. The zombie argument
shows that the mind as the realm of subjectivity is not part of physical
reality but something different, nonphysical. Therefore, if the world were
materialistic, it (given all the same physical facts) should be a world of
phenomenal zombies. However, because we are not phenomenal zombies, materialism
is false.
Amusingly, in the modern philosophy of mind, there are directions that
deny the existence of mind as “subjective dimension”. Eliminativism directly
denies the existence of sensations, emotions, thoughts, desires, etc., and
contends that these concepts are part of the mistaken theoretical system
created for the purposes of explanation and prediction of behaviour – “the folk
psychology” – that should be replaced with scientific theoretical system
explaining the human behaviour directly in (neurophysiological) terms of brain
states. Behaviourism and functionalism, although they do not deny the existence
of sensations, emotions, thoughts, desires, etc., ignore the usual sense of
these concepts and, instead, ascribe them an entirely different, nonphenomenal
sense so that they mean nothing subjective. From the point of view of these
theories, our world is a world of phenomenal zombies (we are phenomenal
zombies) and, thus, materialism is true.
[1] Searle J. “Consciousness Denied:
Daniel Dennett’s Account” // Searle J. The Mystery of Consciousness. – pp.
95-131.
[2] Popper K. Unended Quest. – p. 219.
[3] Note that
materialistic theories of mind (various versions of the philosophy of
materialism) are not to be confused with scientific theories about the material
(neural) correlates of consciousnesses. The latter can be advanced and
estimated quite independently of the former. For example, C. Koch, one of
the co-authors of the theory that the neural basis of consciousness (the neural
correlate of subjective experiences) is certain 35-75 Hz oscillations in the
cerebral cortex, explained in an interview that this theory is not meant to be an explanation of
consciousnesses per se, as the realm of subjectivity, and suggested that
this problem may not have a scientific
solution:
“Well, let’s first
forget about the really difficult aspects, like subjective feelings, for they
may not have a scientific solution. The subjective state of play, of pain, of
pleasure, of seeing blue, of smelling a rose – there seems to be a huge jump
between the materialistic level, of explaining molecules and neurons, and the
subjective level. Let’s focus on things that are easier to study...”
(“What is
Consciousness”, Discover, November
1992, p. 96. –
quot. by: Chalmers D. “Facing Up to
the Problem of Consciousness”)
[4]
Perry, J. Knowledge, Possibility, and Consciousness
[5] see Dictionary: begging the
question
[6] Levine J. Purple Haze
[7] Cf: D. Chalmers about the identity postulate:
“... it makes the identity an explanatorily primitive fact about the world. That is, the fact that certain physical/functional states are conscious states is taken as a brute fact about nature, not itself to be further explained. But the only such explanatorily primitive relationships found elsewhere in nature are fundamental laws; indeed, one might argue that this bruteness is precisely the mark of a fundamental law. In postulating an explanatorily primitive "identity", one is trying to get something for nothing: all of the explanatory work of a fundamental law, at none of the ontological cost. We should be suspicious of such free lunches…”
(Chalmers D. Moving Forward on the Problem of Consciousness. – p. 13)
[8] Chalmers, D. J. Imagination,
indexicality, and intensions. – p. 182-183.
[9] Let us consider the following
example. Imagine that there is a very powerful demon – omnipotent and omniscient as
far as physical reality is concerned. He can instantly obtain the knowledge
of all physical facts in the universe (physical omniscience), and he can
instantly change all physical facts however he wants. Nevertheless, he does not
interfere with the course of the physical processes in our universe. Instead,
he has a whim to create another – parallel – world that would be an exact
physical copy of our world with all exactly the same physical events but with
some time lag – for example, 5 minutes. Knowing all the physical information
about our universe how it was 5 minutes ago, the demon has created its exact
physical copy down to each of the smallest subatomic microparticle. Since that
moment, he constantly (let us suppose, each milliardth of milliardth fraction
of a second) traces all physical relations and properties of all physical
elements of this parallel world and compares them with the corresponding
physical relations and properties of all physical elements of our world 5
minutes ago; if there are some divergences (however small), he instantly
eliminates them. If so, then in this parallel world, there is my exact physical
copy that repeats (down to the smallest detail) all my actions of 5 minutes
ago, and inside its body, there are exactly the same physical processes that
occurred in my body 5 minutes ago. However, this creature, unlike me, has no
mind (as the realm of subjectivity, “phenomenal space”); it is a phenomenal
zombie.