B. Philosophy of Mind: 2nd Extract

The epi-phenomenal theory

THE idea of my conscious states as mere by-products of corresponding physical processes does take a bit of getting used to. My life unfolds before me like a film before a captive audience. Every decision I am conscious of having made — say, my decision long ago to enrol on a philosophy course — is the result of a purely physical process going on inside my brain. My brain is the organ that actually deliberated, came to a decision and then ordered my hand to write the letter. My conscious awareness of the weighing of pros and cons, the agonising over alternatives, the feeling of resoluteness that led to a definite decision, were just so many effects of blind brain processes, effects cut off from any causal influence in the physical world, or indeed on one another. It seems I had no choice but fatalistically to observe the process of GK's deliberating, coming to a decision and acting as one after the other these events came up inside my consciousness. My physical body and brain may be active, but my 'I', or, rather, the collection of 'my' conscious states is purely passive.

The fact that a philosophical theory makes us feel uncomfortable, however, is no reason for rejecting it. Here is one example, one might say, of the way philosophy changes our perception of the world and of ourselves. So long as one keeps one's mind fixed on the thing that matters — that there is something here inside me in addition to the physical — then one will accept whatever consequences logically follow from that view. It is perhaps more unsettling, however, to realise that the supposedly 'scientific' credentials of this epi-phenomenal theory turn out to be more than a little suspect. The view that everything that happens in the physical world has a physical cause may be all that the scientific study of human life strictly requires. We may not yet fully understand exactly how the human brain works — how this immensely complicated biological 'computer' carries out its functions, what its 'program' is or how it evolved from the less complex brain of the ape — but we are committed to the view that there is ultimately a complete answer to be given in physical terms, even if at present we do not know all the details.

Yet mention of evolution raises a rather embarrassing question. If all the properties of the brain, every function that it is capable of performing, are ultimately the result of millions of years of evolution, what is the function of this extra 'something' that appears — seemingly miraculously — on the 'inside'? Why, in addition to my brain's internal representations, its physical 'beliefs' and 'perceptions', should there need to occur the mental copies of these physical states, if the occurrence of such purely subjective mental events has no physical effect? By hypothesis, no evolutionary survival advantage is conferred on an individual who happens to possess something extra 'inside' in competition with a being similar in every way on a physical level, whose brain does not have the capacity to produce this extra non-physical quality.

The story will therefore have to be something like this. Not every quality or attribute of human beings, it might be said, necessarily points to some survival advantage. The shape of our ears, or our having an appendix, or many other physical features are just unavoidable by-products of the process of evolution. The evolutionary route taken to get to where we are now has thrown up all sorts of physical features that were perhaps useful at the time and which when they ceased to be useful were retained because they did not confer any evolutionary disadvantage. Other physical features are the result of the physical and biological constraints on growing a human body, just as some aspects of car design are dictated by the nature and limits of the manufacturing process rather than by the qualities that would, from a strictly functional or aesthetic point of view make for the 'ideal' car. Subjective states of consciousness come into a similar category. They are a mere by-product of the evolutionary process, by-products that have neither a beneficial nor a detrimental effect, for they have in fact absolutely no effect at all.

Now it just so happens, the epiphenomenalist will say, that when a brain and nervous system of sufficient complexity evolves, subjective states of consciousness begin to be produced or emitted. The production of subjective mental states is purely a bonus so far as evolution is concerned. The physical representations in the brain that the physical subject talks about as its 'beliefs', 'feelings' or 'perceptions' give rise to an additional subjective awareness whose nature the subject cannot communicate to any other subject. The eyes take in light of certain wavelengths, the brain processes the information and recognises 'blue', and the vocal chords emit the sound corresponding to the words, 'I'll take three bunches of blue irises please. ' But while all this is going on something extra is happening, something that I am aware of from my own case. As my physical eyes and brain physically register blue, an actual experience of blue colours my subjective awareness.

There is, by hypothesis, no physical explanation for this phenomenon. From the point of view of an account of the changes that physically take place in the world and in the physical agents who 'perceive', form 'beliefs' and 'act', there is no need for such a subjective experience of blue to occur. A zombie whose external behaviour was indistinguishable from a human being, but for whom all was darkness 'inside' would recognise blue irises just as well as I. All one can say is that it is simply an ultimate, inexplicable fact about the world that in addition to the physical, the objective, the outer, there appears in each one of us — or at least in me — something mental, subjective, inner.

It is easy to trip up on language here. It is true to say of a human being who is awake, taking in information from her environment, that she is 'subjectively' or 'consciously' aware of what is going on. Our everyday language has no other hooks to grip the world than those provided by the purely physical, objective circumstances of an individual's using her capacity to perceive and process information in order to get about the world, to behave in the way that a human being normally behaves. The indescribable inner, the extra something 'on top' that the epiphenomenal dualist insists on calling attention to has no role to play in ordinary, non-philosophical speech. But just because something is never talked about doesn't mean that it doesn't exist. Descartes has taught us, the epiphenomenalist will say, to see something that previously we didn't see, to be aware of certain aspects of reality that do not figure in 'ordinary, non-philosophical speech'. This new perception changes everything, and yet it changes nothing. We carry on as before, talking of one another's 'perceptions, thoughts and feelings'. — Only now, as philosophical converts to dualism, in uttering these words we are tempted to give a sly wink to one another, as if to say, 'We know what we're really talking about, don't we?'

Just at this point, the reader may begin to gain an inkling that while as dualists we may seem to be pointing out philosophically interesting features of the nature of subjectivity and of the mind, in reality we are staring into the abyss of metaphysical illusion. Ordinary language is too crude, it seems, to convey the essence of what we 'mean'. Instead, we nod and wink at one another. Indeed, we have no other choice. Imagine you are at a party, talking to a stranger, and the conversation comes around to, 'What do you do?':

'Actually, I'm a philosophy student. '

'That's funny, so am I! Is there any problem area you're particularly interested in?'

'Well, for some time I've been fascinated by the mind-body problem. '

'Amazing! I spend most of my time these days thinking about the mind-body problem. Do you hold any particular view? Are you an identity theorist, a dualist, or what?'

'To tell you the truth, I incline towards epiphenomenalism. '

'An epiphenomenalist! At last! I thought I was the only one... '

Watching this stranger's lips move, a strange sense of detachment seems to envelop you. It could be the third Martini, or perhaps fatigue from too many late nights. But just at this moment, a disturbing thought surfaces in your consciousness. 'How do I know that this person isn't a zombie?' As an epiphenomenalist, you admit as a matter of course the logical possibility that an individual with all the physical characteristics of a living human being might be a zombie. Thankfully, such sceptical thoughts do not normally cloud your everyday dealings with your fellow human beings. We do not indulge in sceptical doubt just because doubt is 'possible'; if we did, we should go mad. Only now, the train of thought continues inexorably. Just suppose the person talking to me is a zombie. How can a mere zombie believe that it is 'more than mere physical stuff'? How could it think that there is an indescribable something that 'colours' its subjective state of consciousness when, by hypothesis, there is nothing 'inside'?

On reflection, nothing could be easier. We have already emphasised that everything a person says and does is a consequence of changes in one's physical state. Therefore, if any person is moved to declare, 'I am an epiphenomenalist,' it is the physical state of her brain that is causing her vocal chords to utter those sounds. If she writes an article defending epiphenomenalism and sends it off to the journal Mind, it is the physical state of her brain that caused her fingers to type the words, caused her hands to put the article in the envelope and her legs to carry her down the road to the post office. The occurrence of subjective, inner states is, according to the theory of epiphenomenalism, an effect of physical processes, never a cause. At first sight, this indeed looks like a knock-down refutation: — 'A zombie would say exactly what you're saying!'

Or perhaps not quite. The epiphenomenalist can reply, 'A zombie whose brain was in a physical state identical to the state of my brain would utter the sounds that you hear as the words, "I am an epiphenomenalist," but for it, lacking the attributes of consciousness, the sounds would have no meaning. As far as the states of my consciousness are concerned, you of course are free to entertain whatever doubts you like, but I know that I have consciousness. Therefore, when I utter the words, "I am an epiphenomenalist," I mean what I say, and I know exactly what it is that my words mean. I mean that I am an epiphenomenalist. No more, no less. That is what I truly believe. '

Is that an adequate reply to the attempted knock-down refutation? One would have to say that what the self-professed epiphenomenalist has just said is an adequate reply to the objection, 'A zombie would say that,' stated in just those terms. A zombie would not say that, because a zombie cannot 'say' things, any more than a tape recorder can say things. However, all that means is that one has to be a little more subtle in stating the objection.

If one takes someone as intending to make a truthful assertion, certain basic conditions need to be fulfilled. First, there is an assumption that the person understands what she is saying. Second, we are expected to assume that the person believes that what she is saying is true. There is, thirdly, the implication that it is in some sense because what the person is saying is true — if indeed it is true — that she has come to say what she says. To take a trivial example, suppose I say, 'It is raining. ' In saying that, I take myself to know what my words mean, and to have uttered those words because I think it is raining. What's more, I imply that I have adequate grounds for making that assertion, that I am not simply guessing wildly but have genuine reason to think that it is raining, a reason ultimately connected with the fact that there is indeed rain outside. (I may have just looked out of the window, or else someone whom I trust has just informed me. ) The reformulated objection to epiphenomenalism may now be stated as follows: no judgement expressed in the words, 'I am an epiphenomenalist,' could ever satisfy these three conditions for making an assertion.

The reason, briefly, is this. We are prepared to listen to someone when they tell us, 'It is raining,' because we take it that, barring errors or mistakes, or deliberate deception, they would not have uttered those words if there hadn't in fact been any rain. Yet when a philosopher says, 'I am an epiphenomenalist,' we have to take into account the fact that according to that very theory, if there had not occurred 'inside' the individual concerned the subjective states to whose existence the theory is meant to call attention, the very same words would still have been uttered!

Yet if I am convinced by the epiphenomenalist theory, then surely I know what it is that I believe, even if I cannot expect anyone else to take my honest declaration of my belief at face value? — In considering one's own case, we have to take a slightly different tack. Let us focus on my confidence in the truth of what I believe. If I seriously thought that I might have been prompted to say what I said only because I had fallen victim to fallacious philosophical reasoning, then I would naturally wish to rule that possibility out. But that is just what I cannot do. I already know that there must be an intelligible explanation, couched in terms that do not imply the existence of anything 'inner', why a zombie whose brain was in the same physical state as my own would be prompted to utter the words, 'I am an epiphenomenalist. ' Perhaps I may never discover the explanation, but I know all the same that there has to be one. Indeed, it can only be that very explanation that accounts for my uttering the words that I utter in expressing my supposedly 'inner' judgement that I am an epiphenomenalist.

Everywhere I twist and turn, all I can do is come up with words, words that my zombie double would use too. The only thing I can do, it seems, is remain silent and direct my gaze 'inwards' (except of course that the zombie will say that too!).