Consciousness and Space

By Colin McGinn
Rutgers University

The location of consciousness

Descartes famously held that, while the essence of body is spatial extension, the essence of mind is thought. Thought is taken to be the defining attribute of incorporeal substance - substance that is non-spatial in nature. He writes: 'For if we...examine what we are, we see very clearly that neither extension nor shape nor local motion, nor anything of this kind which is attributable to a body, belongs to our nature, but that thought alone belongs to it.'(1) The mental and the spatial are thus mutually exclusive categories.

It is hard to deny that Descartes was tapping into our ordinary understanding of the nature of mental phenomena when he formulated the distinction between mind and body in this way - our consciousness does indeed present itself as non-spatial in character. Consider a visual experience, E, as of a yellow flash. Associated with E in the cortex is a complex of neural structures and events, N, which does admit of spatial description. N occurs, say, an inch from the back of the head; it extends over some specific area of the cortex; it has some kind of configuration or contour; it is composed of spatial parts that aggregate into a structured whole; it exists in three spatial dimensions; it excludes other neural complexes from its spatial location. N is a regular denizen of space, as much as any other physical entity. But E seems not to have any of these spatial characteristics: it is not located at any specific place; it takes up no particular volume of space; it has no shape; it is not made up of spatially distributed parts; it has no spatial dimensionality; it is not solid. Even to ask for its spatial properties is to commit some sort of category mistake, analogous to asking for the spatial properties of numbers. E seems not to be the kind of thing that falls under spatial predicates. It falls under temporal predicates and it can obviously be described in other ways - by specifying its owner, its intentional content, its phenomenal character - but it resists being cast as a regular inhabitant of the space we see around us and within which the material world has its existence. Spatial occupancy is not (at least on the face of it) the mind's preferred mode of being.

No doubt this is connected with the fact that conscious states are not perceived. We perceive, by our various sense organs, a variety of material objects laid out in space, taking up certain volumes and separated by certain distances. We thus conceive of these perceptual objects as spatial entities; perception informs us directly of their spatiality. But conscious subjects and their mental states are not in this way perceptual objects. We do not see or hear or smell or touch them, and a fortiori do not perceive them as spatially individuated.(2) This holds both for the first- and third-person perspectives. Since we do not observe our own states of consciousness, nor those of others, we do not apprehend these states as spatial. So our modes of cognition of mental states do not bring them under the kinds of spatial concepts appropriate to perceptual acquaintance. Perceptual geometry gets no purchase on them. And this is not just a contingent fact about the mind.(3)

Nor do we think of conscious states as occupying an unperceived space, as we think of the unobservable entities of physics. We have no conception of what it would even be to perceive them as spatial entities. God may see the elementary particles as arrayed in space, but even He does not perceive our conscious states as spatially defined - no more than He sees numbers as spatially defined. It is not that experiences have location, shape and dimensionality for eyes that are sharper than ours. Since they are non-spatial they are in principle unperceivable.

This is I think what people have in mind when they aver that 'consciousness is not a thing'. The thought expressed here is not the trivial one that to refer to consciousness is to invoke a category of events or states or processes and not a category of objects or continuant particulars. Our intuition that conscious states are not spatial is not the intuition that no state is an object. For ordinary physical states and events are spatial entities in the intended sense: we apprehend events as occurring in space, and states are features of spatially constituted objects. So it would be wrong to offer a deflationary interpretation of our non-spatial conception of consciousness by insisting that it comes to nothing more than a recognition that talk of consciousness is talk of events and states - just like talk of explosions and motions and electric charge. The non-spatial nature of consciousness, as we conceive it, is much more radical than that diagnosis suggests. Descartes was not committing the simple howler of failing to notice that conscious phenomena are not objects at all and hence not spatial objects. In fact, even when we do speak of something that belongs to the category of continuant object, namely the subject of consciousness, we are still insistent upon its non-spatial character.(4) The self is not a 'thing' either, in the intended sense. The realm of the mental is just not bound up in the world of objects in space in the way that ordinary physical events are so bound up. So, at any rate, our pretheoretical view assures us.

That may seem exaggerated, at least under one interpretation of the idea of connectedness to the spatial world. For, it might be said, we do in point of fact locate conscious events in the spatial world - not very precisely perhaps, but at least in a fairly systematic way. Thus we take each subject of consciousness to be somewhere in the vicinity of a distinguished body, and we locate conscious events in the approximate neighbourhood of the physical object we call the brain. We certainly do not suppose that I am in some other place than my body, and we locate my thoughts nearer to my head than to my feet. So, it may be said, we do grant spatial characteristics to consciousness, at least of a rudimentary sort.

I think this point should be granted, at least so far as it goes: but it does not go very far in undermining the intrinsic non-spatiality of the mental. How do we actually make the locational judgements about consciousness that we do? Not, clearly, by perceiving that conscious events occupy particular places; rather, by trading upon certain causal considerations. Events in particular physical objects are directly causally involved in changes of mental state, and we locate the mental change roughly where those causally proximate physical objects themselves are located. I am where that body is whose physical states bear most directly on my mental state; and my states of consciousness are situated in the vicinity of that brain whose activity is most directly implicated in the causal relations controlling my mental life. For example, my visual states are in the whereabouts of the eyes and brain that produce them, and not somewhere in (say) the Grand Canyon (unless my eyes and brain happen to be there). But this kind of causally based location of the mental should be taken for what it is. First, it is parasitic on a prior location of physical objects; there is no independent route onto mental location, since that is based solely on bearing causal relations to things that can be nonderivatively located. If we imagine abrogating these causal relations, by considering a world in which there are no psychophysical causal connexions, but only intra-mental ones, then we see that in such a world no form of spatial location would be available for mental events. They would not be tied down to any location at all, no matter how vague. Locating mental events as we do in the actual world is merely 'theoretical', as one might say - a sort of courtesy location. Considered in themselves, intrinsically, we do not regard mental events as having location. The imprecision of our locational judgements here is a mark of this. Second, to allow that consciousness can be roughly located is not to grant it the full panoply of spatial predications. We still do not get predications of shape, size, dimensionality and so on. And this shows that such spatiality as we do allow to mental matters is of a second-class and derivative nature. Descartes himself might readily have allowed this kind of causally based location of the mental while still insisting that concepts of extension have no proper application to the mental.

It might now be objected that there are some mental events that do permit precise location, and that this is based on something like immediate perception. Thus I feel a pain to be in my hand, and that is indeed exactly where it is. Isn't this just like seeing the physical injury to my hand that produces the pain? Well, it is true enough that the pain presents itself as being in my hand, but there are familiar reasons for not taking this at face value. Without my brain no such pain would be felt, and the same pain can be produced simply by stimulating my brain and leaving my hand alone (I might not even have a hand). Such facts incline us to say, reasonably enough, that the pain is really in my brain, if anywhere, and only appears to be in my hand (a sort of locational illusion takes place). That is, causal criteria yield a different location for the pain from phenomenal criteria. And anyway bodily pain is an unusual case and does not generalise to other mental phenomena (perhaps this is why in ordinary language we speak of pain as a bodily state rather than a mental one).

It is instructive to consider the notion of spatial exclusion in relation to the mind. A well-known metaphysical principle has it that no two material objects (of the same kind) can occupy the same place at the same time. It is in the very nature of space and objects that there should be this kind of necessary exclusion. And analogous principles can be formulated for material events, states and processes. Now ask whether this principle applies also to mental items. Can two subjects of awareness occupy the same place at the same time? Can two thoughts be spatio-temporally coincident? Can two bodily sensations? The questions seem misconceived, since the issue does not really arise for mental things. We want to say: 'Well, if mental things had location and other spatial properties, then there might be such exclusion; but since they don't it is not clear what to say. Maybe, for all we know, they can be spatio- temporally coincident, since nothing in their intrinsic nature rules it out.' The fact is that the question is too much like asking whether two numbers can be at the same place at the same time. We just do not conceive of these things in ways that bring them within the scope of the principle of spatial exclusion. This is a way of saying that the notion of solidity has no application to mental phenomena. If the essential mark of the spatial is competiton for space, as the metaphysical principle records, then the mental lacks that essential feature.

In view of the above considerations there is something highly misleading about the popular suggestion that mental phenomena have the same sort of conceptual status as the posits of physical science: that is, that both are unobservables postulated to make the best sense of the data. Apart from the obvious point that we also know about our mental states 'from the inside', there is a crucial disanalogy here, which underscores the sui generis character of the mental case. While we think of the unobservables of physics as existing in space and hence in spatial relation to the things we do observe, we do not think of the mental states that explain behaviour in this way. Explanatory posits they may be, at least from the third- person perspective, but they are not the reassuring spatial entities that other explanatory posits are. It is thus far more puzzling how they relate to behaviour, especially causally, than is the relation of atomic events to the macroscopic behaviour of material bodies. In the physical case, we have notions of contact causation and gravitational force acting across space, but in the mental case it is quite unclear how these causal paradigms are supposed to apply. How do conscious events cause physical changes in the body? Not by proximate contact, apparently, on pain of over-spatialising consciousness, and presumably not by action-at-a-distance either. Recent philosophy has become accustomed to the idea of mental causation, but this is actually much more mysterious than is generally appreciated, once the non-spatial character of consciousness is acknowledged. To put it differently, we understand mental causation only if we deny the intuition of non-spatiality. The standard analogy with physical unobservables simply dodges these hard questions, lulling us into a false sense of intelligibility.(5)

I conclude, then, from this quick survey of somewhat familiar terrain that consciousness does not, on its face, slot smoothly into the ordinary spatial world. The Cartesian intuition of unextendedness is a firm part of our ordinary conception of the mental. In advance of theoretical reconstruction consciousness is not spatially well-behaved. We shall next look at some consequences of this, inquiring what theoretical response should be made to it.

The origin of consciousness

If consciousness is not constitutionally spatial, then how could it have had its origin in the spatial world? According to received cosmology, there was a time at which the universe contained no consciousness but only matter in space obeying the laws of physics. Then the evolution of life began and matter started clumping together in novel ways, driven by the mechanism of natural selection. Soon, in cosmic time, neural nuclei appeared, leading to brains of various sizes and structures - and along with that (as we think) came consciousness. Evidently, then, matter fell into ever more complex and ingenious arrangements and as a result consciousness came into the world. The only ingredients in the pot when consciousness was cooking were particles and fields laid out in space, yet something radically non-spatial got produced. On that fine spring morning when consciousness was first laid on nature's table there was nothing around but extended matter in space, yet now a non- spatial stuff simmered and bubbled. We seem compelled to conclude that something essentially non-spatial emerged from something purely spatial - that the non-spatial is somehow a construction out of the spatial. And this looks more like magic than a predictable unfolding of natural law. Let us call the problem of how this is possible the 'space problem' with respect to consciousness.(6)

Notice that this problem has no parallel in the evolution of life forms per se. These are indeed cosmic novelties, but they do not essentially transcend the mechanisms of spatial aggregation, and we have a good theory of how the novelty is generated. There is no space problem in explaining the emergence of organisms as such; that problem only begins to bite when conscious states enter the scene. To put it in Descartes' terms: how can something whose essence is to be non-spatial develop from something whose essence is to be spatial? How can you derive the unextended from the extended? Note too that this problem has no parallel in the relation between the abstract and the physical, since, though non-spatial, the abstract is not supposed to have emerged from the material. The problem arises from a specific clash between the essence of consciousness and its apparent origin.

We might be reminded at this point of the big bang. That notable occurrence can be regarded as presenting an inverse space problem. For, on received views, it was at the moment of the big bang that space itself came into existence, there being nothing spatial antecedently to that. But how does space come from non-space? What kind of 'explosion' could create space ab initio? And this problem offers an even closer structural parallel to the consciousness problem if we assume, as I would argue is plausible, that the big bang was not the beginning (temporally or explanatorily) of all existence.(7) Some prior independent state of things must have led to that early cataclysm, and this sequence of events itself must have some intelligible explanation - just as there must be an explanation for the sequence that led from matter-in-space to consciousness. The brain puts into reverse, as it were, what the big bang initiated: it erases spatial dimensions rather than creating them. It undoes the work of creating space, swallowing down matter and spitting out consciousness. So, taking the very long view, the universe has gone through phases of space generation and (local) space annihilation; or at least, with respect to the latter, there have been operations on space that have generated a non-spatial being. This suggests the following heady speculation: that the origin of consciousness somehow draws upon those properties of the universe that antedate and explain the occurrence of the big bang. If we need a pre-spatial level of reality in order to account for the big bang, then it may be this very level that is exploited in the generation of consciousness. That is, assuming that remnants of the pre-big bang universe have persisted, it may be that these features of the universe are somehow involved in engineering the non-spatial phenomenon of consciousness. If so, consciousness turns out to be older than matter in space, at least as to its raw materials.(8)

However that may be, we are still faced with the space problem for consciousness. How might it be dealt with? There are, historically, two main lines of response to the problem, commonly supposed to be exclusive and exhaustive. One response denies a key premise of the problem, namely that mind sprang from matter. Instead, mind has an autonomous existence, as independent of matter as matter is of mind. Perhaps mind has always existed, or maybe came about in some analogue of the origin of matter, or owes its existence to a direct act of God. In any event, mind is no kind of out-growth of matter but an independent ontological category. Thus we have classical dualism, Descartes' own position. In effect, dualism takes the space problem to be a reductio of the emergence hypothesis. Mind and matter may causally interact (let us not inquire how!) but it is absurd, for dualism, to suppose that mind could owe its very being to matter. That is simply metaphysically impossible, according to dualism. You can no more derive the unextended from the extended than you can derive an ought from an is.(9)

A second response questions what we have been assuming so far, namely that consciousness is inherently non-spatial. We may grant that we ordinarily conceive of it in this way, but we should insist that that mode of conception be abandoned. Here we encounter, it may be said, yet another area in which common sense misconceives the true nature of reality. In fact, conscious states are just as spatially constituted as brain states, since they are brain states - neural configurations in all their spatial glory. Thus we have classical materialism, the thesis that consciousness is nothing over and above the cellular structures and processes we observe in the brain.(10) Since these admit of straightforward spatial characterisation, so, by identity, do conscious states. The case is analogous to the following: to common sense physical objects appear solid, but science tells us that this is an illusion, since they are really made up of widely spaced particles in a lattice that is anything but solid. Somewhat so, the materialist insists that the appearance of non-spatiality that consciousness presents is a kind of illusion, and that in reality it is as spatial (even solid!) as the cell clusters that constitute the brain.(11) It is Descartes' assumption of unextendedness that is mistaken, according to materialism, not the emergence hypothesis.

Now it is not my intention here to rehearse any of the usual criticisms of these two venerable positions, beyond noting that both have deeply unattractive features, which I think we would be reluctant to countenance if it were not for the urgency of the problem. These are positions we feel driven to, rather than ones that save the phenomena in a theoretically satisfying way. My purpose is to identify a third option, and to explore some of its ramifications. The point of this third option is to preserve material emergence while not denying the ordinary non- spatial conception of consciousness. The heart of the view, put simply, is this: the brain cannot have merely the spatial properties recognised in current physical science, since these are insufficient to explain what it can achieve, namely the generation of consciousness. The brain must have aspects that are not represented in our current physical world-view, aspects we deeply do not understand, in addition to all those neurons and electro-chemical processes. There is, on this view, a radical incompleteness in our view of reality, including physical reality. In order to provide an explanation of the emergence of consciousness we would need a conceptual revolution, in which fundamentally new properties and principles are identified. This may involve merely supplementing our current theories with new elements, so that we need not abandon what we now believe; or it may be - as I think more likely - that some profound revisions are required, some repudiation of current theory. Consciousness is an anomaly in our present world- view, and like all anomalies it calls for some rectification in that relative to which it is anomalous, more or less drastic. Some ideal theory T contains the solution to the space problem, but arriving at T would require some major upheavals in our basic conception of reality.

I am now in a position to state the main thesis of this paper: in order to solve the mind-body problem we need, at a minimum, a new conception of space. We need a conceptual breakthrough in the way we think about the medium in which material objects exist, and hence in our conception of material objects themselves. That is the region in which our ignorance is focused: not in the details of neurophysiological activity but, more fundamentally, in how space is structured or constituted. That which we refer to when we use the word 'space' has a nature that is quite different from how we standardly conceive it to be; so different, indeed, that it is capable of 'containing' the non-spatial (as we now conceive it) phenomenon of consciousness. Things in space can generate consciousness only because those things are not, at some level, just how we conceive them to be; they harbour some hidden aspect or principle.

Before I try to motivate this hypothesis further, let me explain why I think the needed conceptual shift goes deeper than mere brain physiology, down to physics itself. For, if I am right, then it is not just the science of matter in the head that is deficient but the science of matter spread more widely.(12) A bad reason for insisting that the incompleteness reaches down as far as physics is the assumption that physiology reduces to physics, so that any incompleteness in the reduced theory must be reflected in the reducing theory. This is a bad reason because it is a mistake to think that the so-called special sciences - geology, biology, information science, psychology, etc - reduce to physics. I will not rehearse the usual arguments for this, since they have been well marshalled elsewhere.(13) If that were the right way to look at the matter, then physics would be highly incomplete and defective on many fronts, since all the special sciences have outstanding unsolved problems. But it is surely grotesque to claim that the problem of how (say) the dinosaurs became extinct shows any inadequacy in the basic laws of physics! Rather, the intransitivity of problems down the heirarchy of the sciences is itself a reason to reject any reductionist view of their interrelations. So it is certainly an open question whether the problem of consciousness requires revisions in neurophysiology alone, or whether those revisions will upset broader reaches of physical theory. It depends entirely on what is the correct diagnosis of the essential core of the problem. And what I am suggesting is that the correct diagnosis involves a challenge to our general conception of space. Given the fact of emergence, matter in space has to have features that go beyond the usual conception, in order that something as spatially anomalous as consciousness could have thereby come into existence. Somehow the unextended can issue from matter in space, and this must depend upon properties of the basis that permit such a derivation. It therefore seems hard to avoid the conclusion that the requisite properties are instantiated by matter prior to its organisation into brain structure. The brain must draw upon aspects of nature that were already there. According to our earlier speculation, these aspects may be connected to features of the universe that played a part in the early creation of matter and space itself - those features, themselves pre-spatial, that characterised the universe before the big bang. Consciousness is so singular, ontologically, and such an affront to our standard spatial notions, that some pretty remarkable properties of matter are going to be needed in order to sustain the assumption that consciousness can come from matter. It is not likely that we need merely a local conceptual revolution.

The nature of space

Let us perform an induction over the history of science. There is what might be called a 'folk theory of space', a set of beliefs about the general nature of space that comes naturally to human beings in advance of doing any systematic science. It probably develops, in part, out of our perceptual systems and it serves to guide our behaviour; we might think of it as a visuo- motor space. No doubt it would be difficult to describe this mental representation of space in full detail, but I think it is fair to report that it encodes a broadly Euclidian geometry and that it regards motion as relative to the position of the earth. It also has some firm ideas about what it is for something to be somewhere. Now it is a platitude of the history of science that this folk theory has come under successive challenges, which have substantially undermined and reformed it. Indeed, most of the big advances in physics and astronomy have involved revising our folk theory of space. Let me mention, sketchily, a few of these, to give flavour to what I am building up to. First, of course, there was the replacement of the geocentric view of the universe with the heliocentric one, and then the replacement of that with an a-centric view. The Newtonian scheme takes the earth to be just one body in space among others, subject to the same laws of motion; our earthly position does not define some privileged coordinate with respect to which everything else must be measured. We must also recognise the existence of a new force, gravity, which acts across space without benefit of a mechanical medium. Thus space has a hitherto unsuspected power - which Newton himself regarded as dubiously 'occult'. Later, and just as famously, the developments surrounding relativity theory called for the abandonment of a Euclidian conception of physical space, to be replaced by geometries that are counterintuitive to the folk theory of space. Curved space-time was the upshot, among other exotica. Quantum theory also prompts serious questions about the nature of space: particles have no unique location, and various 'nonlocality effects' upset our usual ideas about physical things and their causal dependence. What it is to be in space becomes obscure. Then we have such speculations as string theory and twistor theory and the many- worlds hypothesis, in which further 'hidden' dimensions are introduced. Our folk theory of space has been regularly hung out to dry. From the point of view of the divine physicist, space must look to be a very different creature from that presented to the visuo-motor system of human beings.

All this is suggestive of a certain diagnosis of the problem with respect to consciousness. For here too we have a phenomenon that puts pressure on our ordinary conception of space. Conscious phenomena are not located and extended in the usual way; but then again they are surely not somehow 'outside' of space, adjacent perhaps to the abstract realm. Rather, they bear an opaque and anomalous relation to space, as space is currently conceived. They seem neither quite 'in' it nor quite 'out' of it. Presumably, however, this is merely an epistemological fact, not an ontological one. It is just that we lack the theory with which to make sense of the relation in question. In themselves consciousness and space must be related in some intelligible naturalistic fashion, though they may have to be conceived very differently from the way they now are for this to become apparent. My conjecture is that it is in this nexus that the solution to the space problem lies. Consciousness is the next big anomaly to call for a revision in how we conceive space - just as other revisions were called for by earlier anomalies. And the revision is likely to be large-scale, despite the confinement of consciousness to certain small pockets of the natural world. This is because space is such a fundamental feature of things that anything that produces disturbances in our conception of it must cut pretty deeply into our world-view.

No doubt this is all very mind-stretching and obscure; and it is of course not a theory but an indication of where the correct theory might lie. There is a rather Kantian ring to it, what with noumenal space containing all the answers that phenomenal space cannot provide. But I am not really distressed by the lack of transparency of the conjecture, because I think that it is quite predictable that our intellects should falter when trying to make sense of the place of consciousness in the natural order.(14) And here is where the bitter pill beneath the sweet coating begins to seep through. For to suggest that we need a radically new conception of space is not to imply that we can achieve any such conception, even in principle. It may be merely to point to the place at which we are incurably ignorant. To explain what I mean let us back up for a while to consider the question of human epistemology - the question of what we can and cannot know.

The limits of human knowledge

It is easier not to know than to know. That truism has long had its philosophical counterpart in rueful admissions that there are nontrivial limits on what human beings can come to grasp. The human epistemic system has a specific structure and mode of operation, and there may well be realities that lie beyond its powers of coverage. Chomsky, in particular, regards our cognitive system as a collection of special-purpose modules that target specific areas of competence, and fail to target others.(15) The language faculty is one of these, which itself breaks down into a number of sub-modules. It is targeted away from certain possible languages as a by-product of its positive targeting: human languages, yes; Martian languages, no. Chomsky adopts essentially the same conception of what he calls our 'science-forming' faculties: they too are just a collection of contingent cognitive structures, biologically based, that have arisen in us over the course of evolution. They have a phylogeny and an ontogeny, and they operate according to certain specific principles, these being realised by machinery in the brain. They are as natural as any organ of the body. Given this, there is absolutely no reason to believe that the faculties in question are capable, at this period in our evolution, of understanding everything there is about the natural world. Viewing the matter in a properly naturalistic spirit, with the human species counted as just one evolved species among others, the overwhelming probability is that we are subject to definite limits on our powers of understanding, just as every other species is. We hardly suppose that the bipedal species who preceded us, traces of which sometimes show up in the fossil record, were themselves as intellectually advanced as we are, with our massively protruding frontal lobes and impressive manual dexterity. We just need to project ourselves into the position of the species that might succeed us to see how contingent and limited our capacities are.

This general viewpoint makes one open to the possibility that some problems may simply exceed our cognitive competence. But I think something more specific is suggested by our discussion so far: namely, that our troubles over space and consciousness arise from certain deep-seated features of the way we represent space to ourselves. We are, cognitively speaking, as well as physically, spatial beings par excellence: our entire conceptual scheme is shot through with spatial notions, these providing the skeleton of our thought in general. Experience itself, the underpinning of thought, is spatial to its core. The world as we find it - the human world - is a preeminently spatial world. This is a line of thinking powerfully advocated by P.F. Strawson, who focuses particularly on the role of space in our practices of identification.(16) The guiding Strawsonian thesis is that the distinction between particular and universal, and hence between subject and predicate, is founded on the idea, or experience, of spatial distinctness. We regard x and y as distinct particular instances of the same universal P just in so far as we acknowledge that x and y are at distinct places. That is what the non-identity of particulars fundamentally consists in for us. Without that spatial resource we should not be able to frame the conception of multiple instances of a single property. And this implies that the very notion of a proposition presupposes the notion of spatial separation, and hence location. At root, then, our entire structure of thought is based upon a conception of space in which objects are severally arrayed; though once this structure is in place we can extend and refine it by means of analogy and relations of conceptual dependence.

Now consider thought about consciousness. The non- spatiality of consciousness presents a prima facie problem for our system of thought: how, if the Strawsonian thesis is right, do we contrive to think about consciousness at all? It ought to be impossible. The answer lies in those analogies and dependencies just mentioned. We go in for spatialising metaphors and, centrally, we exploit relations to the body in making sense of numerically distinct but similar conscious episodes. We embed the mental in the conceptual framework provided by matter in space. We don't reduce it to that framework; we appeal, rather, to systematic relations that the two realms manifest. But - and this is the crucial point for me - this is to impose upon conscious events a conceptual grid that is alien to their intrinsic nature. It is as if we must resort to a spatial scheme because nothing else is available to us, given our de facto reliance on spatial conceptions. It is not that this scheme is ideally fitted to embed the target subject-matter. Thus we get a kind of partial fit in which location is causally based and notions of extension find no purchase at all. Consciousness comes out looking queasily quasi-spatial, a deformed hybrid. Deep down we know it isn't just extended matter in space, but our modes of thought drag it in that direction, producing much philosophical confusion. We represent the mental by relying upon our folk theory of space because that theory lies at the root of our being able to represent at all - not because the mental itself has a nature that craves such a mode of representation.(17)

To represent consciousness as it is in itself - neat, as it were - we would need to let go of the spatial skeleton of our thought. But, according to the Strawsonian thesis, that would be to let go of the very notion of a proposition, leaving us nothing to think with. So there is no real prospect of our achieving a spatially nonderivative style of thought about consciousness. But then, there is no prospect of our developing a set of concepts that is truly adequate to the intrinsic nature of consciousness; we will always be haunted by the ill-fitting spatial scheme. No doubt this lies behind the sense of total theoretical blankness that attends our attempts to fathom the nature of consciousness; we stare agape in a vacuum of incomprehension. Our conceptual lens is optically out of focus, skewed and myopic, with too much space in the field of view. We can form thoughts about consciousness states, but we cannot articulate the natural constitution of what we are thinking about. It is the spatial bias of our thinking that stands in our way (along perhaps with other impediments). And without a more adequate articulation of consciousness we are not going to be in a position to come up with the unifying theory that must link consciousness to the world of matter in space. We are not going to discover what space must be like such that consciousness can have its origin in that sphere. Clearly, the space of perception and action is no place to find the roots of consciousness! In that sense of 'space' consciousness is not spatial; but we seem unable to develop a new conception of space that can overcome the impossibility of finding a place for consciousness in it.(18)

In saying this I am presupposing a robust form of realism about the natural world. That we are constrained to form our concepts in a certain way does not entail that reality must match that way. Our knowledge constitutes a kind of 'best fit' between our cognitive structure and the objective world; and it fits better in some domains than others. The mind is an area of relatively poor fit. Consciousness occurs in objective reality in a perfectly naturalistic way; it is just that we have no access to its real inner constitution. Perhaps surprisingly, consciousness is one of the more knowledge-transcendent constituents of reality. It must not be forgotten that knowledge is the product of a biological organ whose architecture is fashioned by evolution for brutely pragmatic purposes. Since our bodies are extended objects in space, and since the fate of these bodies is crucial to our reproductive prospects, we need a guidance system in our heads that will enable us to navigate the right trajectory through space, avoiding some objects (predators, poisons, precipices) while steering us close to others (friends, food, feather beds). Thus our space- representing faculties have a quite specific set of goals that by no means coincide with solving the deep ontological problems surrounding consciousness and space. Many animals are expert navigators without having the faintest idea about the true objective structure of space. (The eagle, for one, still awaits its sharp-beaked Newton.) There is simply no good reason to expect that our basic forms of spatial representation are going to lead smoothly to the ideal theory of the universe. What we need from space, practically speaking, is by no means the same as how space is structured in itself.

I suspect that the very depth of embeddedness of space in our cognitive system produces in us the illusion that we understand it much better than we do. After all, we see it whenever we open our eyes and we feel it in our bodies as we move. (Time has a similar status.) Hence the large cognitive shocks brought about by the changes in our view of space required by systematic science. We are prone to think that we can't be all that wrong about space. I have been arguing that consciousness tests the adequacy of our spatial understanding. It marks the place of a deep lack of knowledge about space, which is hard even to get into focus. No doubt it is difficult to accept that two of the things with which we are most familiar might harbour such intractable obscurities. Irony being a mark of truth, however, we should take seriously the possibility that what we tend to think completely transparent should turn out to transcend altogether our powers of comprehension.


1. Cottingham, Stoothoff, Murdoch 1985: 195.

2. Obviously I am not denying that there is a sense in which we can perceive persons, by perceiving their bodies; my point is that we do not perceive the psychological subject qua psychological subject. If you like, we do not perceive the I of the Cogito.

3. We see an echo of this in two doctrines of Wittgenstein's: that self-ascription is not based upon observation; and that the notion of inner ostension (pointing) is ill-defined. In this respect, at least, Wittgenstein and Descartes converge on the same fundamental insights. I think, in fact, that a good deal of Wittgenstein's philosophy of mind is based upon a repudiation of a spatial model of the mind.

4. Again, I am assuming that the conscious subject is not simply identical with the body. But my overall position does not depend upon this, since the point applies equally to conscious states themselves.

5. Of course, it is a presupposed materialism that permits the usual insouciance over mental causation. I am simply pointing out that without materialism the claim of mental causation, though no doubt correct, is burdened with severe problems of intelligibility. Once materialism is questioned all the old problems about mental causation resurface.

6. There are some suggestive remarks on the spatiality of organisms and the non-combinatorial nature of the mental in Nagel 1986: 49-51.

7. Here I am raising highly controversial issues. Let me just say that all the arguments I have heard for supposing the big bang to be the beginning of everything take the form of inferring an ontological conclusion from epistemic premisses - to the effect that since we can't know anything about any earlier state we should suppose there to be no such state. But that, I assert, is an idealist fallacy. Sometimes it is suggested that time began with the big bang, because of its supposed internal connexion with space. Again, I find such arguments unconvincing. But, actually, my point is consistent with allowing time to start with the big bang, since we could always introduce a notion of explanation that did not require temporal priority. I myself see no good reason to rule out a picture of the universe in which radically new realities come into existence as a result of other realities. Just as it took gravity to convert the gaseous early state of the universe into the clumpy galaxies we now take for granted, so the big bang may have been just one episode in which the universe underwent a radical transformation. In general, I think people are far too ready to suppose that nothing antecedent to the big bang could have existed, usually on shaky philosophical grounds - ultimately of an anthropocentric nature. (No doubt I shall get into trouble for poking my nose into the cosmologists' business here!).

8. Clearly, there are many large assumptions here: not merely that reality did not begin with the big bang, but also that the prior reality has somehow persisted into the post-big bang state of the universe, presumably by virtue of some sort of conservation principle. These seem to me pretty plausible assumptions, though how to establish them is another question. I should note also that the speculation in the text pertains only to the non-spatiality of consciousness; I am not suggesting that all the features of consciousness could be explained by pre-big bang properties. In this paper I am leaving on one side questions about the subjectivity of consciousness, qualia and so on.

9. In McGinn 1993 I give dualism the best defence I can muster, though it is not a position I subscribe to.

10. Functionalism and allied doctrines should be included here, since they are broadly materialist. Computationalism is harder to classify because of tricky questions about the ontology of computer programmes. One one natural interpretation computer programmes are constituted by abstract objects, so they are non- spatial. This may or may not be a good way to capture the non- spatiality of consciousness (actually not), but the view is clearly no longer materialist.

11. This is an unspoken assumption of large tracts of contemporary philosophy of mind. Even those who recognise that consciousness poses problems for materialism in virtue of its phenomenal character seldom acknowledge that its non-spatiality is also a major stumbling-block for materialism - despite the fact that Descartes took it (and not qualia) to be critical.

12. Cf. Penrose 1989, where consciousness is also taken to challenge the adequacy of current physics.

13. See, for instance, Fodor 1974.

14. See McGinn 1991, 1993.

15. See Chomsky 1976, 1988.

16. See Strawson 1959, 1974.

17. The inadequacy of spatially-based identification of conscious particulars is a contention of mine, not Strawson; he seems far more sanguine that the spatial scheme is a satisfactory framework for talk of the mental.

18. Compare cognitive beings who have mastered Euclidian geometry but who constitutionally lack the mathematical ability to develop non-Euclidian geometry. An instructive parable on cognitive limitation, with special reference to space and geometry, is Abbott 1884. I am saying that we too are Flatlanders of a sort: we tend to take the space of our experience as the only space there is or could be.


Abbott, E.A. (1884). Flatland: A Romance of Many Dimensions. New York: Signet Classic.

Chomsky, N. (1976). Reflections on Language. UK: Fontana.

Chomsky, N. (1988). Language and Problems of Knowledge. Cambridge, MA: MIT Press.

Cottingham, J., Stoothoff, R., Murdoch, D. (1985). The Philosophical Writings of Descartes, Volume I. Cambridge: Cambridge University Press.

Fodor, J. (1974). Special Sciences. Synthese, 28, 77-115.

McGinn, C. (1991). The Problem of Consciousness. Oxford: Basil Blackwell.

McGinn, C. (1993). Problems in Philosophy. Oxford: Basil Blackwell.

McGinn, C. (1993). Consciousness and Cosmology: Hyperdualism Ventilated. Consciousness, Davies, M., Humphreys, G.W., eds. Oxford: Basil Blackwell.

Penrose, R. (1989). The Emperor's New Mind. Oxford: Oxford University Press.

Strawson, P.F. (1959). Individuals. London: Methuen.

Strawson, P.F. (1974). Subject and Predicate in Logic and Grammar. London: Methuen.