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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 –

Ïîäïèñü: Reminder: phenomenal zombies – imaginary creatures 
that have exactly the same bodies as we have, 
that behave (move hands, feet, etc.) exactly as we do, 
but subjectively feel nothing and are aware of nothing: 
with and within their bodies, everything occurs automatically 
according to physical laws,
without any feeling and awareness whatsoever)

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 mindthat 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 Dennetts 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.

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