by Ted Honderich

This paper, the fifth on a theme, is the main source of talks given to the Toward the Science of Consciousness Conference for 2003 in Prague and the same conference for 2005 in Copenhagen. It is a departure from traditional and still orthodox accounts of consciousness, mind and brain, and the explanation of mental events. For an argued survey of these accounts, and a particular allegiance now abandoned in favour of Consciousness as Existence, go to Mind Brain Connection and Mind and Brain Explanation. For what may be the mainlast word on all this from me, 213,000 words come to think of it, there is the OUP book Actual Consciousness.

Abstract: Consider three answers to the question of what it actually is for you to be aware of the room you are in. (1) It is for the room in a way to exist. (2) It is for there to be only physical activity in your head, however additionally described. (3) It is for there to be non-spatial facts somehow in your head. The first theory, unlike the other two, satisfies criteria for an adequate account of consciousness itself. The criteria have to do with the seeming nature of this consciousness, and with subjectivity, reality and non-abstractness, mind-body causation, and the differences between perceptual, reflective and affective consciousness. The theory of consciousness as existence is not open to the objection of a deluded brain in a vat. The theory explains its own degree of failure in characterizing consciousness. It releases neuroscience and cognitive science from nervousness about consciousness, and leaves all of consciousness a subject for science. The theory is a reconstruction of our conception of consciousness. It may be that we should carry forward several theories of consciousness. But they will have to be compared in terms of truth to the criteria for an adequate theory.

1. Perceptual Consciousness as Existence

   There has been a kind of reminder but no decent definition in the idea that for a thing to be conscious is for there to be something it is like to be that thing (Sprigge, 1971; Nagel, 1974). This is so because of the circularity of the mouthful. You can only make sense of it by taking it as this: for a thing to be conscious is for there to be something it is like for that thing to be conscious. So consciousness is not in sight of being defined along these lines as a way of being. You can get well on the way to that disappointing truth just by noticing Searle's approving remark that there is something it is like to be a dolphin, but not something it is like to be a shingle on a roof (Searle, 1992, p. 132). He doesn't see he lets the cat out of the bag.

   But you can usefully just ask what it is like to be conscious. You can usefully ask yourself what it is like for you to be conscious of this room right now. That is, you can ask for the seeming nature of the fact or thing to you, the appearance of it, the phenomenology of it. This might of course be the real nature too -- some appearances are also the reality, the very nature of the thing.

There is a good answer to the question of what it is like for you to be conscious of or aware of this room now. For you to be conscious of the room is, it seems, for the room somehow to exist. Not you, but the room. In fact there is no better phenomenological answer so-called. Is it not superior to all others?

Think of the family of answers that what it is like for you to be conscious of this room now is for there to be a thing or substance and stuff out of space, but still somehow in your head (Descartes, 1641, 1649). The mysterious tension or contradiction about space probably helps this answer, since being conscious seems as well as is mysterious to us, but it leaves the answer as thin as it is.

Think of another family of answers. What is like for you to be conscious of this room now is for for there to be a neural instantiation in your head of a computational or functional sequence (Kim, 1998, Chs. 4, 5). Or an electromagnetic field (Pocket, 2002). Or, God help us, what your consciousness seems to be to you is a generating in your head of macroscopic quantum coherence, with Bose Einstein condensates combining and microtubules microtubuling (McFadden, 2002).

   These answers to the phenomenological question are of course taken directly from two families of views as to the very nature of your consciousness. They are the best phenomenological answers those views can give. Those views are not strengthened by abandoning themselves, so to speak, and telling some ad hoc tale, as the physicalist ones do, when they turn to the matter of so-called appearances. Our consciousness itself, after all, whatever depth or process or machinery or other fact underlies or explains it, is not itself hidden from us. None of it is hidden, whatever else may be. If you maintain consciousness as distinct from anything else really is something, you should show us this accords with its seeming nature.

   You can make absolutely literal sense of the idea that what it is to be conscious of this room is the room's somehow existing.

For you in particular to be conscious of this room now is for there to be things somehow existing outside of your head, for a state of affairs somehow to be there, a kind of world. That is to say, firstly, that the things are in space-time and that they have other properties, such as colour. Some can be called chairs. To say that this state of affairs exists is to say, secondly, that the chairs and so on (a) depend on the way underlying things are -- atoms, fields etc. -- and also that the chairs and so on (b) depend on you, on how you are perceptually and also conceptually, and, more particularly, on you neurally or on some of your neural processes.

This way of existence of the chairs and the like makes this state of affairs like another -- it is tempting to say it is about as real as another.

That other one is the physical existence of the room at a certain level. That consists in things being in space and time, and (a) dependent on underlying things -- atoms, fields etc. -- and also (b) dependent not on a particular person but rather on perceiving persons in general or maybe qualified perceiving persons in general. You can add again that really it is dependency on all their neural processes.

   The pretty ordinary idea in play here is that the physical world is things in space-time with perceived properties like colour and also things in space-time without perceived properties but in causal connection with the first lot of things (Quinton, 1973). The physical world is at two levels -- chairs etc. and atoms etc.

So, to repeat, what it is for you to be conscious of the room is a fact outside your head, quite similar to but not the same as the fact of the perceived and public physical world outside your head.

Both are out there. Neither is mysterious. Your world of perceptual consciousness and my different one are not made 'mental' in a funny or unanalysed sense by particular human dependencies -- no more than the perceived physical world is made so by its general human dependency. None of this has anything to do with Bishop Berkeley or the dictum that to be is just to be perceived (Honderich, 1998, pp. 148-155, 1999, pp. 69-71).

Worlds of perceptual consciousness are in fact epistemologically prior and less theorized that the physical world in either of its levels. Views from somehow come before and are no such abstractions as the view compounded from nowhere. Certainly there is what we call the world seen my way -- and, incidentally, if it isn't my perceptual consciousness, what is it?

    Ask, certainly, why anyone would want to think along these near-physicalist or naturalist lines about perceptual consciousness -- want to try on what can be called the idea of consciousness as existence with respect to perceptual consciousness (Honderich, 1998, 1999, 2001, 2003).

The reason is that very generally speaking there are only two other sorts of answers, touched on a moment ago, to the question of the nature of consciousness, and they are still terrible. Nobody believes the first option when they are not half-dreaming. Nobody believes the second when they are not overcome by science in a certain way or trying to get through the peer-review of the Journal for Consciousness Studies -- which, I must tell you confidentially, the paper you are hearing did not. Let me say a word about the two sorts of views.

2. Spiritualism, Devout Physicalism

First, you can half-dream that that what still has the misleading name of dualism is the case -- that consciousness is a non-spatial thing and stuff, maybe somehow in the head. Or rather, you can be committed to something like this, however quiet you are and however much you keep your head down, by being unable to swallow devout or real physicalism and having nothing else to say. This is probably the position of most philosophers, maybe even most philosophers of mind.

It shouldn't be called dualism, though, for a few reasons. One is that these days most monisms, identity theories, physicalisms and even materialisms are dualistic in the sense of adding something else to physical properties or ordinary physical properties. Davidson says his monism is not nothing-but materialism (1980). Searle's impulse to and inconsistency about dualism is plain (Honderich, 1995). The idea that consciousness is non-spatial is better called spiritualism, in a bare use of the term that makes it equivalent to dualism in another and traditional use of that term.

Whether or not a dualism in the contemporary sense is also a spiritualism, which may not be easy to tell, it is likely to be something else that it will be useful to name -- a cranialism. That is a view that just locates consciousness in the head. It does so despite our universal reluctance actually to say Yes when faced with the question of whether our consciousness is something in our head (Honderich, 2003, pp. 7, 19).

The other option from spiritualism is the devout physicalism. You can say and write, in a career that keeps an eye on some of science, maybe two, and is forgetful of reflective experience, that being conscious or aware of something has only physical properties in the head. So devout physicalism is that being aware of something has only neural properties -- thought of computationally or with microtubules to the fore or in any other way you like. This other cranialism may or may not be involved in some sort of dualism in the contemporary sense. The name of devout physicalism is a reminder that for it, at bottom, and despite the elaborations, consciousness remains only physical properties in the head.

Nobody not on the philosophical job of trying to approximate more to some of science believes this either. What we all know, to make use of a pefectly proper and enlightening parody, is that consciousness, isn't just cells, however fancily or fancifully conceived. Everybody on the job tries to give a place to or register what they know when they're not on the job. But they can't do it if they have it that consciousness has only neural properties or conceivably silicon or otherwise physical properties, no matter how they are conceived additionally.

The different view gestured at so far, consciousness as existence with respect to perceptual consciousness, is certainly closer to devout physicalism than to spiritualism. Despite being a contemporary dualism, like so much else, it is indeed near-physicalism.

Another way of seeing it is that it takes perceptual consciousness to be fairly close to what some others call just the content of perceptual consciousness. The same is true, although the rest of the story is different, with what you can call the other two parts, sides or elements of consciousness. Those are reflective or cognitive consciousness, and affective or somehow desirous consciousness.

But let me pause for a moment to protest that I am not mad as a hatter, or as an epiphenomenalist.

It would be mad to say, as a piece of conceptual or linguistic analysis, that what we ordinarily have in mind in talking of being aware of this room, and talking of perceptual consciousness generally, is a state of affairs outside the head. Cranialism has a hold on us and our language. It would be and is as mad to say, by the way and of course, that what we ordinarily have in mind in talking of being aware of this room is something in the head -- neural clicking or pulsing of whatever kind, or even clicking or pulsing in part.

The enterprise in hand, rather, instead of being conceptual or linguistic analysis, is one of conceptual construction or reconstruction, of which a little more will be said in the end. For now, to go further with that job, notice that there are widely-agreed criteria of adequacy for a concept or conception of consciousness, widely-agreed constraints on a good one.

3. Conciousness-Criteria, and Reflective and Affective Consciousness

One criterion of adequacy is the phenomenological one, so-called, of which you have heard something in connection with your being aware of this room and of which more can be said (Honderich 1999, p.67).

Another criterion, the main one in some sense, is that a good conception has to recognize and give real and unique sense to our conviction of the subjectivity of consciousness. Subjectivity has to be made sense of, not denied, reduced or replaced.

A third criterion is making consciousness real as against abstract, which means physical or close to it. That, by the way, excludes what you can call abstract functionalism or abstract cognitive science both from any physicalism and from being a real starter in the consciousness stakes (Kim, 1998, Chs 4, 5; Honderich, 1995, p. 369).

A fourth criterion is that an account has to make mind-body or consciousness-physicality causal interaction possible and indeed ordinary.

A fifth is that a good account of consciousness has to make it different in its three parts, sides or elements, which plainly it is, and probably to make perceptual consciousness somehow fundamental and permeating.

Our most laboured-on conceptions of consciousness these days, all the devout physicalist theorizing in the best journal on the subject, are mainly products of a simple and pious attention to the third or reality criterion, and a reasonable attention to the fourth one about causal interaction. The laboured-on ideas, despite declamation and philosophically-unproductive technicality, fail the second or subjectivity test dismally. Subjectivity certainly isn't cells. As you have already heard, they also fail the first or phenomenological test. Abstract functionalism, by the way, evidently fails not only the third test, about physicality or something close to it, but also the causal interaction test. The laboured-on ideas, and abstract functionalism, do badly on the fifth test too, about differences in consciousness.

Consider if the reconstruction being proposed does better, anyway with perceptual consciousness. What it seems to be for you to be aware of this room is surely for the room to exist in a clear sense. But above all, the big difference between consciousness and all else is really catered for in the reconstruction -- we have a clear sense in which consciousness truly is subjective (Honderich, 1999, p. 71; 2001, p. 7). The state of affairs that is your awareness isn't mine, and it isn't ever the physical state of affairs either. It can be a lot different in its properties. So too does the reconstruction do well with causal interaction and the other tests (Honderich, 1999, p. 73; 2003, pp. 2, 7).

So -- what it is for someone to be conscious of this room is for things to have properties, be in relations, undergo the changes that are events -- as a result of both things in your head and things underlying the ones in the state of affairs. But have you been digging in and saying that this state of affairs can be redescribed more plainly just as a property or attribute of the person? That we ordinarily say that consciousness is a property of a person and we can stick to this line here?

Well of course you can say something like that. You can say that somewhere's having a three-piece suite in it is an armchair's having the property of having another one next to it and also a sofa. Or that the Atlantic Ocean is in fact a large basin in the earth's surface having the property of being full of water. But your being conscious is no more a property of you, strictly speaking, than it is of the underpinning atoms and what-not. Your being conscious, on the present story, is ordinarily and more enlighteningly described as a state of affairs including the several things.

   Certainly, on this story, your being conscious is not just the particular fact of the state of affairs being in part dependent on your neural activity. That dependency-relationship, reportable by a true conditional proposition, does not begin to have the features required by the five criteria of consciousness. No doubt there might be profit in a lot more reflection on things or substances, properties, relations, events, states of affairs, worlds and so on -- in short on the categories of reality, the metaphysics implicit in all our talk. But we have a grip on these things in advance of the further reflection.

   It seems to me that to insist that your being conscious has to be your having a property, where that is to insist on more than the possible careless use of an expression, is just to be wedded to the sort of idea to which consciousness as existence is opposed. So your proper response is to dispute what is said for the theory. Let us have your argument.

To say a word now not about perceptual but rather about reflective and affective consciousness, the account of them in terms of consciousness as existence is less neat. But it does continue the same story (Honderich, 2003). And it does make perceptual consciousness pretty fundamental and certainly permeating with respect to reflective and affective consciousness -- thinking and desiring in general.

Reflective consciousness consists, first, in the existence of representations or symbols in perceptual consciousness -- i.e. actual things in space-time with the character of all symbols. That character, in brief, is that they have some of the causal properties of the things represented. Reflective consciousness, secondly, consists not in these external but rather in internal representations -- a personal language of thought and feeling if you like (cf. Fodor, 1979).

So, what other call the contents of reflective consciousness are upgraded into the thing or stuff itself. In the conciousness there is no funny relationship to the representations. Whatever multitude of relations may be involved, including a causal one issuing in the activating of representations, no such relationship with a self or whatever is part of my thinking in its various forms.

Affective or desire-related consciousness is in that respect the same -- no internal relationship. It consists, firstly, in things in perceptual consciousness being of certain kinds that we ordinarily desire: bigger, faster, quieter, deadlier and so on. It is, secondly, certain bodily things -- say the sensations connected with fear. It is, thirdly, representations of behaviour or action.

The existence-conditions or dependence-conditions of the parts of reflective and affective consciousness that are not in perceptual consciousness will be analagous to those parts that are in it. With these internal representations, there will be a kind of double-dependency, related to both the double dependencies of things of perceptual consciousness and things of the perceived physical world. The story is as close to devout physicalism as you can get and still be true to the subject-matter of consciousness -- what it's like for a start, to remember the first criterion of adequacy, and also its subjectivity and so on.

Since it's also the case that the theory of consciousness as existence is different from what has been going on in the philosophy of mind, let alone the science of mind, which is different, let me say some more about it. Three things in particular -- about past theories of perception and brains in vats, consciousness as baffling, and consciousness as existence in relation to neuroscience and some attendant philosophy of mind.

4. Representative Theory, Realist Theory

Consciousness as existence, in so far as it concerns perceptual consciousness, is a little closer to one of the two families of theories of perception in the past of philosophy and indeed its present.

One is the representative theory of perception, or phenomenalism. It is to the effect that what you are aware of and what I am aware of when, as we say, we both see the chair, is not numerically one thing. I am aware of my sense-datum, percept, sensation or whatever, and you are aware of yours. However qualitatively alike, there are two of these internal things to which we are limited in our perceptual experience. Such a theory is of course identified with the empiricism of Locke, Berkeley and Hume. The best discussion of it in the 20th Century, and a tentative defence, was given by A. J. Ayer (1973)

The other theory of perception is closer to ordinary belief. It has the tremendous recommendation, as against the representative theory, of getting each of us out of solitary confinement. It is that when you and I see the chair, as we say, what we are aware of is indeed one thing, a physical object. If the representative theory, as Dretske (1995) usefully remarks, confines us in our seeing to mental television, the realist theory (Price, 1932) saves us from this, puts us in touch with the real world. But what this relation, this being-directly-in-touch-with, comes to -- this is not clear at all. Remember that the realist theory is indeed about consciousness in the widely-shared sense, not the relation of photons, retinas and the visual cortex.

The theory of perceptual consciousness as existence is evidently a little closer to the realist theory. The existence theory is also about something outside the head, and on the way to being physical. As against this, there is a large difference between the existence theory and the realist theory, and also between the existence theory and the representation theory of perception. It has to do with relations.

The realist theory necessarily involves not only the physical world but the unclear relation to it. The relation has to be in there. How it is to be conceived is indeed unclear -- all that has ever been said is that it is not an inferential relation, certainly not a relation of conscious inference. More generally, it's not a relationship such that one becomes aware of something, maybe a chair, by in a prior sense being aware of something else. Don't say the relation isn't photons and so on but is just seeing, by the way -- that's what we're supposed to be analysing.

An obscure relation has been as much a part of all representative theories, I suspect. Brentano's idea of consciousness serves as an example (Brentano, 1973; Bell, 1990, Ch. 1). When I see a chair, as we ordinarily say, there is something called activity directed on an object or activity with reference to a content, which latter things are of course internal to the experience and are of the order of a sense-datum, percept or whatever. In addition to them there is the directedness. Elsewhere in philosophy, there is a lot of stuff, less clear, to the effect that all consciousness is or includes self-consciousness -- here too something is added to an internal content.

It is a further recommendation of consciousness as existence that it does not load a funny relation into its conception of consciousness itself. Needless to say, your awareness of this room involves the dependency-relations that have been mentioned -- to your neural activity and also a world of atoms etc. That is not to say that what it is for you to be conscious of this room includes in itself a relation to something. What your consciousness consists in no more includes relations explanatory of it than an apple includes its relation to a tree.

5. Deluded Brains in Vats

These remarks about the representative and the realist theories are of use in clarifying the theory of consciousness as existence but they also lead to something else. There is a terrible objection to the realist theory -- to which, as remarked, consciousness as existence is a little closer. The objection is in fact the proposition or family of propositions that leads to the representative theory. It has traditionally been known as the argument from illusion. It is better named the argument from hallucination, or, if you like, the argument from a brain in a vat.

It is not the proposition that there are variations in the experience of different persons having to do with their different perceptual situations and equipments -- the look of the penny and the warm hand in water and so on (Ayer, 1956, 1973). That we see a thing differently, as we say, is no reason for concluding that we do not see one and the same thing. You can add that something that did not look different from different points of view would not be a physical object.

Rather, the essential proposition is that matters could be arranged so that there did occur some perceptual experience that stood in no relation at all to the surrounding physical world -- delusion. The brain in the vat in the laboratory is stimulated by attendant neuroscientists, it is said, so that the visual cortex and so on carries on in such a way that there is experience or awareness as in ordinary experiencing of, say, Wenceslas Square. But, ex hypothesi, Wenceslas Square is not there in the laboratory. Since there is something indistinguishable from actual perceptual experience of Wenceslas Square, it follows that the realist theory of perception is refuted and the representative theory is vindicated.

What is also true, you may suppose, is that the account of perceptual consciousness as existence is done for. There is no Wenceslas Square in the right place to be the state of affairs that is the brain's awareness or experience. Here, as some have said, is a disaster that finishes off an unlikely idea.

There have been attempts made by holders of the realist theory to avoid their disaster, of course. One is the retort that the brain in the vat wouldn't be seeing Wenceslas Square, but just thinking it was seeing it (cf. Snowdon, 1980-1981, McDowell, 1982). That is a little factitious, not quite solid enough to defeat all of Locke, Berkeley, Hume and Ayer. In fact it seems to me doubtful that the realist theory can by this or other means survive the objection.

What is of greater importance now is what is taken as implicit or explicit in that theory and certainly is explicit in brain-in-a-vat ruminations. It is that in ordinary perceptual consciousness, as in the case of the brain in a vat, there is a neural process that is causally or in some other way nomically sufficient for the consciousness. There is a complete causal circumstance, wholly neural, for the consciousness. That is why it is possible for the attendant neuroscientists to get the brain, as is said, to have perceptual consciousness of Wenceslas Square.

Let me forget about the realist theory now and stick to perceptual consciousness as existence. The short story is that the brain-in-a-vat rumination does not defeat it, for a clear and certain reason. Rather than defeat the given theory of consciousness, the brain-in-a-vat offers the possibility of testing the theory.

The theory is that your being aware of this room is a state of affairs in space-time outside your head, a local world, that depends both on underlying things -- atoms, etc. -- and also on your neural processes. So each of those lots of things, to speak ordinarily, is only nomically necessary rather than nomically sufficient for your perceptual consciousness. It is only together that the two lots form a causal circumstance for the awareness.

So the theory specifically does not have the brain-in-a-vat consequence. Rather, it excludes the proposition that a brain in a vat, anyway on current assumptions, could possibly be perceptually conscious. There is no neural sufficient condition to be assembled.

Or, to put the matter differently, there is a way that the theory of perceptual consciousness as existence could be falsified. It can or could be falsified by producing real perceptual consciousness in a brain in a vat. It could be falsified if there was as much reason to believe the brain was as conscious of Wenceslas Square or this room as there is reason to believe we are when we are there.

You will anticipate that I have to, and happily do, put my money on no brain in a vat ever having perceptual experience just as a result of monkeying around with the brain itself. There isn't a possible sufficient condition in the brain for a perceptual experience. (Cf., alas, Honderich 2003, pp. 75-77)

To change the whole speculation, I guess it's conceivable, a wild theoretical possibility, that somebody could produce perceptual experience of the laboratory surroundings rather than Wenceslas Square if they added in a perceptual apparatus and so on to the brain. Then the situation could approximate to what I say is sufficient for perceptual consciousness. If you added in the perceptual apparatus and there still wasn't perceptual consciousness -- I guess according to the brain's reports -- then consciousness as existence would again be refuted.

But all that is science fiction. The important point is that you cannot refute the idea of perceptual consciousness as existence by employing the argument from illusion, hallucination or a brain in a vat.

Notice, by the way, that the theory of consciousness as existence does not make all of reflective consciousness in itself dependent on both what is outside and what is inside a head. In so far as reflective consciousness is a matter of only internal representations, which presumably it can be, it is not dependent on anything extra-cranial.

So the theory of consciousness as existence, despite what it says about perceptual consciousness, doesn't from the start absolutely exclude all successful brain-in-a-vat neuroscientific monkeying. That is probably a good thing. My guess is that a lot of neuroscientists would say that there are some things their successors may be able to do and some things they won't be able to do.

6. Consciousness as Baffling

Let us go on to something related, having to do with the battered old question of whether computers could ever be conscious. That is not the question of whether they can think in the also battered sense of compute, process information or anything of the sort but, in part, the question of whether they can consciously think -- consciously think about absent things.

Could a computer consciously think about Wenceslas Square? There is doubt about that, which is to say that a lot of well-informed and good judges are uncertain about it. As it seems to me, such judges are not just in the grips of habit -- the wide and deep habit of restricting consciousness to biological entities, living things. Surely there must be some other reason than a prejudice for neurons over silicon that explains why we good judges are uncertain. There must be something else about consciousness that explains this. It is reasonable to suppose that there must be something about consciousness itself that explains the doubt.

That reflection can lead to another one. It is that a good theory of consciousness itself will have the recommendation of explaining why we are uncertain about whether machines will ever be really conscious.

To use an analogy, it is rightly said that a good theory of something will include a viable explanation of why other people than the theoretician are in error about the thing. A good theory of moral judgements, maybe one that makes them a matter of desires, will include an error-theory in this sense -- an account of why a lot of other people think some moral judgements are really true. Similarly, you can expect a good theory of something to explain uncertainty about its subject-matter.

A good theory of consciousness, to mention another analogy, will certainly have to give an answer in itself to the question of why there has been a mind-body problem. It will have to give an answer to why almost all philosophers have found it hard to see how consciousness and brains can interact causally. You can add by the way that devout physicalism, in making it incomprehensible that there ever was uncertainty already has a strike against it, maybe two.

To get back to the point, or nearer to it, we can contemplate theories of consciousness from the point of view of whether they explain why we are uncertain as to whether computers will ever be conscious. If you think of the two large familiies of theories mentioned at the start, you will not be long in coming to a thought about one of them, devout physicalism. If it really were the case that a persuasive reconstruction of consciousness was as a sequence of purely neural events, then there wouldn't be any reason in principle why computers couldn't be conscious. We wouldn't be uncertain at all. We could just say, well, no doubt it will happen some day -- they'll get there.

Let us skip over the spiritualism family in this connection and come to consciousness as existence. Can it explain why we are puzzled about what computers might become? That question can be subsumed in a larger one. Let us skip to that.

It is very clear that all of consciousness -- forget about computers -- is somehow baffling. To say it is the hard problem (Chalmers, 1996) about our behaviour and its antecedents seems to me a wonderful understatement -- as wonderful, incidentally, as the idea that there is any other problem at all about consciousness itself. There is nothing else at all like this problem about consciousness itself.

So there is a larger challenge for a theory of consciousness: it should have something to say about why it is so hard to come to a decent conception of consciousness, about why agreement or convergence don't really happen, despite what is said in hopeful articles in encylopedias. Indeed, to come to the sharp end, a point that is only superficially paradoxical, a good theory of consciousness should explain why it itself doesn't secure wide agreement. A good theory of consciousness, in short, needs a theory of its own degree of failure.

   It is a good theory I'm talking about, so it can't be that the theory has in it an explanation of its total failure or real hopelessness or anything well on the way to that. What we need, then, in a pretty good theory -- one that does well or not badly on the other criteria we started with -- is an explanation of a degree of failure. Let us say a good theory has to be baffling to a tolerable degree. You will anticipate that it seems to me that consciousness as existence does well here.

   This theory makes your consciousness into a plenitude. Consciousness is all of what other theories take to be the content of your consciousness, or at least akin to that. It's not just a relation to what they call the content. There is a fullness and variety here over any minute, indeed a richness -- in perceptual, reflective and affective terms. To think of your consciousness over longer time is to think of a plenitude to the power of what? This plenitude  has in it your representations or symbols, your intentions in action and your hopes and values and other desire-related things, and the flow of perception. Your consciousness on this theory is not a relation to an abundance but the abundance itself. It is near enough a literal truth that on this theory the fact of your consciousness is the fact of your life.

To come to a simple conclusion quickly, this plenitude that is your life, if you set out to think about it, is defeating. To try to sum it up generally in thought, to try to come to an analytic abbreviation of it, is necessarily to be in a way baffled. This is no sophisticated or chichi point, say about the available capabilities and representations and what-not being inside the subject-matter. The point is the size and nature of the thing, a life. Your consciousness is not some aspect of a life, just a relation, let alone some odd or puzzling feature attendant on computation, but a life itself. There must be a good sense in which there is no larger subject-matter.

To look quickly at the competititon, can it be said that spiritualism is a theory of consciousness that is to a decent extent baffling? Well, as remarked earlier, some sort of spiritualism is in fact a kind of default position, and a lot of philosophers and others are in that position. But it is rare nowadays actually to think about consciousness and embrace spiritualism. It can barely have the name of a theory, since it is more question than answer. What is this gossamer stuff? How can you have a cause that is nowhere? And so on. This is not a decent theory with an explanation of our resistance to it, but a frustration in itself.

As for devout physicalism, however the pill is coated, I'd better admit that the situation seems to me much the same. To put it one way, this theory too is far too baffling. Anyone not in a way scientized finds just about ludicrous the idea that their consciousness actually consists in no more than action potentials, transmitter-substances, bits of protein, magnetism, or the like. Since the 17th Century when  Hobbes declared his devout physicalism, just about the most resilient proposition in philosophy has been that consciousness isn't just cells (Honderich, 2000).

7. Neuroscience, and Some Attendant Philosophy

   Let me turn now to the relations between the theory you have before you and ordinary neuroscience rather than neuroscience fiction. How does the theory stand to it? The first answer is what we already have in connection with the deluded brain in a vat.

It is that it follows from the theory that the business of ordinary neuroscience is the discovery and understanding of neural correlates of consciousness in two senses: correlates that are necessary conditions and correlates that are sufficient or necessitating conditions. The former have to do with perceptual consciousness, the latter with reflective and affective consciousness. The distinction has to be understood in a way consistent with the intermingling of the three sides of consciousness, of which much might be said.

   That it follows from the theory that neurosience is in part concerned with neural events and processes that are only necessary conditions of consciousness is in one way uncontentious. Finding more necessary conditions, I take it, is the day-to-day business of neuroscience (Kandel et al, 1991). To put this point in one way, the day-to-day business of neuroscience is not discovering laws. It is not the discovery of causal circumstances or absolute nomic correlates in the brain for consciousness. Neuroscientific laws are thin on the ground.

   Still, it is possible to think that this day-to-day business is carried forward on a certain background assumption. It is that for every neural necessary condition for a fact of consciousness, there is also some wholly neural sufficient condition of which the necessary condition is part, a sufficient condition that in theory could be found. Let it be confessed that in the past I myself have put a lot of effort into defending that proposition about neuroscience (Honderich, 1988, 1990, Ch. 2). It was, as it now seems, wasted effort.

   But let us not fall into any of a number of nearby possible confusions.

For a great deal of consciousness in the reflective and affective sides of it, according to consciousness as existence, there are sufficient or necessitating neural correlates to be found in the head. It is only for perceptual consciousness that there are only neural necessary conditions to be found.

That does not mean that are no sufficient or necessitating correlates for perceptual consciousness, but simply that they are both inside and outside the head.

Hence there is no mysterious departure here from a decent assumption of lawlikeness or determinism. All of the consciousness of all the three sorts can be a perfect effect of a causal circumstance -- sometimes a circumstance both internal and external to a head. To put this differently and with Davidson and Anomalous Monism is mind, all consciousness is subject to psychophysical laws, but some escapes psychoneural laws.

Finally, each of the neural events or processes with respect to any consciousness whatever is in a clear sense sufficient or necessitating. That is of course the sense in which, in a certain circumstance where everything else is on hand, including the dryness of the match, a striking of it is sufficient for or necessitates a lighting.

   Do you say, despite all this, that current neuroscience falsifies consciousness as existence because the latter theory allows that some consciousnessness -- roughly speaking, seeing -- depends not only on brain events? Well, I don't agree, but I don't mind the possibility of falsification at all. The theory is testable -- that's fine. Certainly, despite the independent virtues of each, science and philosophy are continuous, as Quine rightly believed (Hookway, 1988).

   This is also the time to make some remarks on four propositions, mainly philosophical, to which neuroscience pertains.

There is the proposition of brain-mind supervenience: consciousness cannot change without a neural change, but a relevant neural state can be replaced by another without a change in consciousness (Davidson, 1980; Kim, 1998, pp. 148-153). That is, the neural-consciousness relation is many-one.

With respect to some consciousness, this is denied by the theory of consciousness as existence, simply because supervenience is a doctrine of neural sufficient conditions everywhere. Again, this is not upsetting. It leaves open the possibility, for example, that there can be different instantiations of a necessary condition.

   Epiphenomenalism is the doctrine or group of doctrines that consciousness is a side-effect of neural activity, but has no effects itself. The efficacy of consciousness is denied. It is a pleasure to record that consciousness as existence, particularly in connection with perceptual consciousness, makes epiphenomenalism the mad proposition that that the external world, so to speak, is causally inefficacious with respect to consciousness.

It is as much of a pleasure to record that consciousness as existence leaves no scintilla of doubt about the evolutionary role of consciousness. If worlds of perceptual consciousness aren't selective with respect to species, what is?

Finally, in passing, it is clear that consciousness as existence shares with what is called externalism or anti-individualism the truth that much of consciousness is outside of heads (Putnam, 1975; Burge, 1979). But consciousness as existence comes to its own different position without reliance on what can seem to be unlikely doctrines about meaning -- and without having Hegel in its past (Honderich, 1993).

   To come back to neuroscience and the rest of science, let me make more explicit the rest of their relation to the theory of consciousness in hand. The short story here is that all of consciousness is a subject for science. No part or aspect of consciousness -- no qualia so-called, no 'insides' so-called of brain events, no curious facts that give Fregean sense rather than reference to terms or the vocabulary of consciousness (Wilson, 1980) -- nothing with respect to consciousness is beyond scientific inquiry and understanding.

   Neuroscience, and also cognitive science when it is not engaged in philosophy, has the correlates of consciousness -- necessary or sufficient -- within its subject-matter. So too the perceptual processes that are fundamental to the dependency of perceptual consciousness on the physical world at its bottom level. So too, plainly, the representations etc. that are the stuff of reflective and affective consciousness.

The only qualification necessary is that these facts are not all public facts but in the defined sense subjective. But subjectivity, of course, is exactly what we expect of consciousness. And of course, there is no barrier to the objective understanding of what is not public, of what is subjective in a plain and unmysterious sense.

   The short story of the relation of neuroscience to consciousness as existence, again, is that neuroscience is freed from any lingering worry that consciousness is outside its grasp. That worry has been owed to the idea that its subjectivity is an elusive fact not open to science. Plainly it is.

8. Postcript on Construction or Reconstruction

   There remains a larger matter to be glanced at rather than opened, let alone considered. It was remarked at the start that consciousness as existence is presented not as a piece of conceptual analysis, but as a construction or reconstruction of our ordinary conception of consciousness. It could have been said, too, that it is not a reporting of any scientific conception, but, perhaps, a reconstruction of some. What goes along with this is a certain diffidence about claiming truth for the theory.

   There is a good deal of philosophy of science and other philosophy relevant to this diffidence. There is conventionalism, originally associated with Poincare (1913) and now in a way with Quine (1953). It is to the effect that scientific theories are conventions, or conventions in part, somehow a matter of choice rather than observation or truth. The same can be said of philosophical theories. Instrumentalism, which makes theories into useful instruments, wholly or partly, is along the same lines (van Fraassen, 1980).

Astronomy, and the philosophy of physics from waves and particles onward also come to mind, as does the under-determination of theory by data. So too competing geometries, and Carnap's alternative languages with different formation and transformation rules, and Kuhn's paradigms in science (1962), and the simple fact that all theories seem to fail in the end. Simpler than all this are familiar facts about different ways of looking at a thing, turning them around, different classifications, and such psychological illusions as the duck-rabbit.

   So, can we say the theory of consciousness as existence, which puts perceptual consciousness outside the head, and makes all consciousness more or less what other theories call the content of consciousness, is somehow and to some extent a matter of simplicity, ontological economy, usefulness, convenience, fruitfulness, or elegance? All of these considerations have been said to make a theory a matter of choice rather than truth in the best sense, which of course is correspondence to facts, and more particularly things.

   To cut this last story short, here are a few propositions.

We might well get a little freer in our thinking about consciousness, hang looser, see that there are things to be said for different conceptions. We might carry several forward together.

It isn't the case, despite this, that at bottom there is some basis for any theory that is wholly detached from truth. I suspect the supposedly separate virtues of theories -- simplicity, ontological economy and the rest -- are really indicators or promisers of more truth. You can't say that inconsistent theories are both true, and you can't whistle it either.

Consciousness as existence is indeed a construction or reconstruction, and maybe it should not clear the board, but in my view it comes closer than anything else to being true to the criteria of adequacy for theories of consciousness.

                                                                                                2 July 2003

A slightly revised version of the paper, along with four other papers on the theme of Consciousness as Existence, appears in On Consciousness (Edinburgh University Press, 2004).

: My thanks are due to Ken Adams, Ingrid Coggin Purkiss, William Fish, James Garvey, Basil Hiley, Derek Matravers, Hugh Mellor, Richard Rawles, Andrew Ross, Barry Smith, Tom Stoneham, Ruediger Vaas, and anonymous referees for this journal.


Ayer, A. J. (1956), The Problem of Knowledge (Harmondsworth: Penguin)

Ayer, A. J. (1973), The Central Questions of Philosophy (London: Weidenfeld & Nicholson).

Bell, D. (1990), Husserl (London: Routledge, 1990).

Brentano, F. (1973), Psychology From an Empirical Standpoint, ed. Oskar Kraus, Linda L. McAlister (London: Routledge & Kegan Paul).

Burge, T. (1979), 'Individualism and the Mental', Midwest Studies in Philosophy, 4.

Carnap, R. (1931), The Logical Syntax of Language (London: Kegan Paul, Trench, Trubner)

Chalmers, D. (1996), The Conscious Mind (Oxford: Oxford University Press)

Davidson, D. (1980), 'Mental Events,' in his Essays on Actions and Events (Oxford: Clarendon Press)

Descartes, R. (1641), Meditations, in Descartes 1968

Descartes, R. (1649), Passions of the Soul, in Descartes 1968

Descartes, R. (1968), The Philosophical Works of Descartes, ed. E. Haldane & G. Ross (Cambridge: Cambridge University Press)

Dretske, F. (1995), 'Naive Realism', in The Oxford Companion to Philosophy (Oxford: Oxford University Press), ed. T. Honderich

Fodor, J. (1979), The Language of Thought (Cambridge MA: Harvard University Press).

Honderich, T. (1988), A Theory of Determinism: The Mind, Neuroscience and Life Hopes (Oxford: Clarendon Press).

Honderich, T. (1990), Mind and Brain (Oxford: Clarendon Press). Reprint of Chs. 1-5 of Honderich 1988.

Honderich, T. (1991), 'Seeing Qualia and Positing the World,' A. J. Ayer: Memorial Essays, ed. A. Phillips Griffiths (Cambridge: Cambridge University Press).

Honderich, T. (1993), 'The Union Theory and Anti-Individualism', in Mental Causation, ed. John Heil and Alfred Mele (Oxford: Oxford University Press).

Honderich, T. (1995), 'Consciousness, Neural Functionalism, Real Subjectivity', American Philosophical Quarterly, 32, 4.

Honderich, T. (1998), 'Consciousness as Existence," in Current Issues in the Philosophy of Mind, Royal Institute of Philosophy lectures for 1996-7, ed. A. O'Hear (Cambridge: Cambridge University Press). This paper is corrected in several respects in Honderich 1999.

Honderich, T. (1999), 'Consciousness as Existence Again," Proceedings of the Twentieth World Congress of Philosophy, Vol. 9, Philosophy of Mind, ed. B. Elevitch (Bowling Green: Philosophy Documentation Center, 1999). Also in Theoria, June 2000, No. 95. This paper corrects Honderich (1998) in several respects.

Honderich, T. (2000), 'Consciousness and Inner Tubes', Journal of Consciousness Studies, 7, 7, 2000.

Honderich, T. (2001), 'Consciousness as Existence and the End of Intentionality', in Philosophy at the New Millenium, Royal Institute of Philosophy Lectures for 2000-2001 (Cambridge: Cambridge University Press).

Honderich, T. (2003), 'Perceptual, Reflective and Affective Consciousness as Existence', in Minds and Persons, Royal Institute of Philosophy Lectures for 2000-2001, ed. A. O'Hear (Cambridge: Cambridge University Press)

Hookway, C. (1988), Quine (Cambridge: Polity).

Kandel, E. R. R., J. H. Schwartz and T. J. Jessell (1991), Principles of Neural Science (New York: Prentice-Hall)

Kim, J. (1998), Philosophy of Mind (Boulder: Westview)

Kuhn, T. S. (1962), The Structure of Scientific Revolutions (Chicago: Chicago University Press)

McDowell, J. (1982), 'Criteria, Defeastibility and Knowledge', Proceedings of the British Academy.

McFadden, J. (2002), 'The Conscious Electromagnetic Information (Cemi) Field Theory: The Hard Problem Made Easy?', Journal of Consciousness Studies, Vol. 9, No. 8.

Nagel, T. (1974), `What Is It Like To Be A Bat?,' The Philosophical Review, 83, 1974. Reprinted in Nagel 1979.

Nagel, T. (1979), Mortal Questions (Cambridge: Cambridge University Press).

Papineau, D. (2000), Introducing Consciousness (Cambridge & New York: Icon/Totem Books).

Pocket, S. (2002), 'Diffciulties with the Electromagnetic Field Theory of Consciousness', Journal of Consciousness Studies, 9, 4, 2002

Poincare, H. (1913), Science and Hypothesis (Washington: University Press of America).

Price, H. H. (1932), Perception  (London: Methuen).

Putnam, H. (1975), Philosophical Papers, Vo.l. 2 (Cambridge: Cambridge University Press)

Quine, W. V. (1953), 'Two Dogmas of Empiricism', in From a Logical Point of View (Cambridge MA: Harvard University Press)

Quinton, A. (1973), The Nature of Things (London: Routledge & Kegan Paul)

Searle, J. (1992), The Rediscovery of the Mind (London & Cambridge MA: MIT Press).

Snowdon, P. (1980-81), 'Experience, Vision and Causation', Proceedings of the Aristotelian Society, 81.

Sprigge, T. (1971), `Final Causes', Supplementary Proceedings of the Aristotelian Society, 45.

van Fraassen, B. (1980), The Scientific Image (Oxford: Oxford University Press).

Wilson, E. (1980), The Mental as Physical (London: Routledge & Kegan Paul).

HOME to T.H. front page
HOME to Det & Free website front page