Bounds of Space

Bounds of Space

The Kant-Strawson thesis is that all possible experience is spatial in character (Strawson calls it the “spatiality thesis”). That is, all appearances are spatial appearances—of extended things existing in an ordered unified Euclidian space separate from the mind. This is how experience makes things seem, even if they are not objectively (noumenally) that way. Then the claim is that we can make nothing else “intelligible to ourselves”—these are the bounds of sense (as opposed to nonsense). Nothing else is even meaningful (to us). This is a bad way to put the point: we can’t make the bat’s sonar experience “intelligible to ourselves” but that doesn’t mean that it (bat experience) is intrinsically unintelligible. It is merely a point about the limits of our imagination and hence knowledge, not about what is logically or conceptually or metaphysically possible. Given that ourexperience is always spatial, we might well not be able to understand any other form of experience, but it doesn’t follow that any such alien experience is impossible. And that is the philosophically interesting Kantian thesis, not the thesis that we are imaginatively limited in certain ways. The latter is a thesis about our cognitive powers not about the metaphysics of experience. So, let’s drop the offending formulation and speak simply of what is really possible, whether we can comprehend it or not. Is the spatiality thesis then true? There are two basic questions: (a) whether every instance of sense experience involves spatial representation, and (b) whether every aspect of an instance of experience is spatial in character. That is: does every experience have some spatial content, and is every aspect of experiential content spatial? The strongest Kant-Strawson thesis would be that every logically possible experience has spatial content and that every aspect of experiential representation is spatial. A weaker thesis would be that all experiences are spatial in some respect but that in other respects they are not spatial: for example, visual experience has spatial content (lines, volumes, shapes) but it also represents color, which is not itself a spatial attribute (I will come back to this).

It seems hard to deny that ordinary human visual experience has spatial content (surely the sense that Kant and Strawson were focussing on). There are, however, marginal cases that might provoke doubt, as with sudden flashes of light generated by the brain from within its own depths, or the kind of sensation we have when our eyes are closed in the dark. Could alien perceivers experience such visual sensations more systematically—a non-spatial world of formless color? Might the first color experiences in the womb represent color non-spatially? Certainly, they might not contain the full range of spatial attributes common to adult visual experience. The question seems debatable; our visual imagination of color seems relatively free of spatial ingredients, so maybe it would be possible to have a form of visual sense experience that proceeds without spatial representations, or has very attenuated ones. Anyway, the real challenge arises from the other human senses, not to mention animal senses that we don’t possess—particularly, smell, taste, and hearing (or electrical and magnetic senses in certain animals). Consider perception of pitch and sound intervals, of sweet and sour tastes, of fragrant and noxious smells: where is the space in all this? It may be that spatial concepts intrude on these sense modalities from elsewhere, but it is hard to deny that they are not intrinsically spatial. Couldn’t there be a being that experienced sounds, tastes, and smells but had no perception as of things extended in space—a space-blind perceiver? Even if the external stimulus was a spatial object, it wouldn’t follow that it was perceived as such. This kind of perception is really nothing like the seeing of extended objects with shapes and sizes. Vision and touch are space-oriented senses, but not so hearing, taste, and smell. Spatial ingredients are here contingent and adventitious. So, the Kant-Strawson thesis looks implausible as applied to all (actual and conceivable) senses. It is quite easy to “make intelligible to ourselves” the possibility of non-spatial experience; we have such experiences all the time, if not in unadulterated form. The core of the experience is space-neutral, space-oblivious. Size and shape are irrelevant, unrepresented.

A more difficult question concerns whether visual and tactile experience is wholly spatial. I will focus on the case of color. Color is certainly experienced as extended: it comes in patches and volumes. But is it a spatial attribute like shape and size? Nothing can be inferred about the space an object takes up from knowledge of its color. If an object is spherical, we can infer that it takes up a spherical quantity of space; but if it is red, we thereby know nothing about its spatial configuration—it doesn’t occupy a “red amount” of space. To be red is not to have a specific spatial attribute, unlike being spherical; it is not itself a spatial determination (to use Kant’s term). This is why it is not studied in geometry: it isn’t a type of figure or form; there are circles and rectangles but not “reds” and “greens” (how many sides do they have?). The concept of angle does not apply to colors. Colors are not modes of extension though they are distributed over extended objects. Perhaps this is not surprising given that colors are projected by the mind: for the mind is not itself an extended geometrical object. Somehow the mind spreads color on objects, but what it spreads is not a mode of space; it’s a bit like sensing a smell from every point of an object’s surface. There is no color already in objective things along with their spatial attributes; it is an imposition from outside. So, the complete spatiality of the objective physical world does not apply to color, which is a subjective contribution. Much the same point could be made about touch and warmth: warmth isn’t an objective spatial attribute but an imposed subjective projection. If this is right, then color and warmth are not themselves spatial features of things that enter into our perceptions of them; so, not every aspect of visual and tactile experience is spatial in nature (also consider brightness). The appearances are not exhausted by their spatial content; they have a different kind of content in addition to the spatial.

It might be said that this does not contradict the spatiality thesis, and that is perfectly correct. The thesis never maintained that only spatial content constitutes the appearances, just that it occurs in every experience. Also, color doesn’t crop up universally in sense experience, unlike space (allegedly). But it does allow us to formulate a new thesis that complicates the picture: we can say that visual experience necessarily incorporates both spatial and non-spatial content, given that color is essential to visual experience. It is true that color doesn’t occur in all sense experience, as space is alleged to, but it does occur in all visual experience, so it is a necessary visual universal. Accordingly, space is not as exceptional as Kant and Strawson make it sound, especially given that it doesn’t apply to all the senses. There isn’t a sharp opposition between space and other attributes of the kind alleged by the spatiality thesis; there is just what is more common and less common. It isn’t that space is the very “form of sensibility” while color is mere local variation with no necessity of its own. Space has no especially unique status among perceived qualities. Different aspects of experiential content are useful to the perceiver as ways of representing the world for various biological reasons, space being one of them; but space is not the real metaphysical essence of experience, the sovereign sine qua non. For some creatures, smell and sound might be the chief engines of survival, with space a distant second (living in the dark will not favor vision).

Strawson sometimes weakens the spatiality thesis to say only that an analogue of space is a necessary feature of all experience. This is very vague and open to accusations of vacuity, but it is a wise move on his part. It is too intellectualist to accommodate simple perceivers, and the emphasis on spatial concepts as constitutive of sensory content adds to that fault. Even when the thesis is restricted to human perceivers it gets things wrong because of statistically unusual humans—infants, the congenitally blind, those with certain sorts of brain damage. Perception is a lot more flexible and multifarious than some philosophers have allowed—a lot more independent of Euclid, Newton, and the Kantian Categories. How we think of the world in our abstract scientific theories is not the best guide to the way animals perceive it in their daily lives. To be sure, it is useful to perceive spatial relations, but many other things are also useful to perceive; and we don’t perceive space in the manner of a metaphysician. Perception is not Newtonian.[1]

[1] Was Kant so enamored of Newton’s physics that he wanted absolute Newtonian space to inhabit the human soul? Wouldn’t this bring the soul closer to God (infinite, absolute, immaculate)? Smell and taste don’t seem this elevated. We might think of infinite absolute space as God in nature, infiltrating the soul of man. So Kant may have dreamed. Here theology, physics, and metaphysics meet.

4 replies
  1. Giulio Katis
    Giulio Katis says:

    As you well point out, it seems rather obvious that experiences are not necessarily purely spatial. In fact, I am inclined to think no experience can be purely spatial – well, at least I am not sure what that would mean. Even some ideal experience of empty open space would need to contain something more, like the experience of pellucidity, for it to not be a pure void. But perhaps I am lacking in imagination!

    As for the weaker hypothesis: would flash blindness count as an experience with no spatial features at all? Or lying still in the pitch dark in complete silence, and then being shocked by a sudden loud sound?


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