Elusive Glue


Muddy Waters



Causation is one of those philosophical topics that drive you up the wall. As soon as you start to think about it you draw a complete blank. As Hume observes: “There are no ideas, which occur in metaphysics, more obscure or uncertain, than those of power,force, energy, or necessary connexion” (Enquiry, p.45).[1]The cement of the universe is so much muddy water. Of course philosophers have done everything in their power to hide this fact from themselves, even going so far as to try to reduce causality to mere regularity. Hume’s own view was that causation is real but incomprehensible (by us). It is neither an affair of the senses nor of reason: we have no sensory impression of necessary connection (which is definitive of causation) but neither is causation grasped by reason (like logic, arithmetic, and geometry). It is a real relation between things but it is not revealed by perceiving them or by merely thinking about them. It fits neither empiricism nor rationalism. It sits uncomfortably between the two, awkwardly and inscrutably. No matter how much you gaze at an object or reflect on it you will never discover causation (as it exists in that object). But perception and reason are our only faculties of knowledge, so the mind draws a blank on the nature of causation. Yet we constantly refer to it, rely on it, and assume its reality. Evidently we can know that it obtains, relying on the observation of regularities of nature, but we can’t fathom its inner nature—or even fathom our lack of fathoming.

The problem concerns not just particular causal relations but also the notions of law and power (disposition, capacity, potential). Objects fall under causal laws and have causal powers: this is why they have the effects they have. But laws and powers are at least as inscrutable as causal relations between particulars; this is an interconnected knot of problems. Perhaps the notion of power concentrates the problem most acutely (as Hume intimates): how are the potential effects of a cause contained in it? Are the effects somehow already present in the cause? Does the cause “refer” to the effects? Are there shadows or signs of the effects lurking silently in the cause? But you can’t discern anything like this if you examine the cause, even going down to its elementary constituents. When a moving object imparts motion to another object by collision is the other object’s motion somehow prefigured in the moving object? It had the potential of creating that effect, so doesn’t it already contain it in someway? What ispotential? It’s a bit like the way the meaning of a word “contains” its uses: they are implicit in it, packed into it—but what does this way of speaking amount to?[2]The problem of causation is how an object can contain what it does not contain. If we think of a cause as a conscious being for a moment, it is as if it knows what effects it can bring about, but only unconsciously: it doesn’t have these effects before its consciousness, but it is subliminally aware of them—they are implicitly known not explicitly known. But that looks like a dodge: they aren’t anticipated in any way that we can discern—the mind of a cause is blank about its future effects. Yet it has the power to bring precisely these effects about, and this power is internal to it, so… Thus the waters fill with mud.

What can we say positively about causation? The logic, semantics, and conceptual analysis of “cause” are not so baffling. Thus “xcaused y” expresses a relation that is irreflexive, asymmetric, and transitive: nothing can cause itself, effects can’t cause causes, and the effects of effects are caused by the initial cause. Semantically, it is plausible to suggest that “cause” generates a transparent context and expresses a relation between events (though this view is not without its critics). The concept may also be analyzable in terms of counterfactuals or other necessary and sufficient conditions. So it is not that we can say nothing about the word and what it means—and much philosophical energy has been expended on these worthy tasks. But they don’t touch the underlying metaphysical and epistemological questions, the ones so memorably raised by Hume. What exactly is causation, and how do we know about it? Specifically, what is it to have a causal power, and how can we know causal powers? There are suggestions—there are always suggestions. One suggestion is that a causal power is identical to a structural property of the object, as it might be molecular structure. But this just pushes the question back: how is the power present in the structure? Isn’t it as invisible as ever? Nor can it be excogitated by pure reason. It can’t be seen and it can’t be deduced—it flouts both empiricist and rationalist epistemology. It isn’t a posterioriand it isn’t a priori. It is a peculiar kind of fact, being neither perceptible (even by extended perception: microscopes etc.) nor rationally apprehended. As Hume would say, it is neither a “matter of fact” nor a “relation of ideas”; it hovers ambiguously between the two. No wonder there has been a marked tendency towards elimination: causation must either be reduced to facts less problematic (regularities, dispositions to project) or eliminated outright. To accept it as it is runs into insurmountable metaphysical and epistemological difficulties. Indeed, it threatens to bring down the most fundamental structures of philosophical thought.

So why not just bring them down? Because we have nothing to put in their place, that’s why. It is not as if we have some otherway to think about causation that we can substitute for the old inadequate dichotomies: the waters are thick with mud and our vision fails us. It is really a horrible problem. Best not even to go near it; just leave it alone to fester. But maybe we can articulate the problem better, gain a better sense of its dimensions and density. Can we at least pinpoint whyit is so difficult? It is in some ways worse than the problem of consciousness, because in that case at least we know what we are talking about—we don’t just referto consciousness, we experienceit. But we don’t experience causation (as opposed to its symptoms), despite our readiness to refer to it. We refer to a we-know-not-what. Appealing to mental causation won’t help, despite our immediate acquaintance with the mental phenomena between which causation holds: for mental causation is as opaque as physical causation (as Hume noted). We can say that physical causation is no less activethan mental causation; the will is not somehow a livelierform of causation. Nor is causation by physical contact more transparent than causation-at-a-distance, since its operation is as obscure there as it is in the remote case. In this respect old-style mechanism offers an illusory paradigm of transparency (this was Hume’s central insight, in effect): it isn’t that causation by contact is quite clearly grasped while causation-at-a-distance must be deemed “occult”. Neither is really intelligible to us, not when you get right down to it. Hume’s billiard balls hit each other, unlike orbiting planets, but their causal powers are no more evident to sense or reason than gravity. For some people this was taken as a reason to eliminate causation altogether from physics, and one can appreciate the motivation.

Can we be more constructive? I think we can say two positive things, though nervously. The first is that nature must be more tightly interlinked than we tend to suppose going by the appearances: causation connects things because any effect of a cause must be somehow written into the cause (though not in a way we clearly conceive). The colliding billiard balls don’t appear to sense perception as having any intelligible connection; nor can human reason discern any such connection: but they must somehow be intelligibly linked. The laws of nature essentially relate separate things, because causal powers are essentially powers to bring about certain specific effects: an object xhas the power to make an object yhave a property P. There is thus more “holism” at work in nature than is apparent to our epistemic faculties. We could introduce the idea of the “causal boundary” of an object to signify the class of objects that fall within its causal reach—for instance, the class of solids a given liquid can dissolve. This class falls within its causal boundary but not its spatial boundary. Then nature will be said to consist of the totality of such causal boundaries—these are the true units of nature.

The second thing we can say is that whatever causal powers are they must be very different from their manifestations in observable phenomena. This is because the manifestations never add up to a causal power, as it exists in objects. It can’t be mere regularity and it can’t be a “categorical base” (e.g. molecular structure)—these are not what the power is or else we wouldknow what it is. Powers must be as different from their manifestations as mental states are from behavior—perhaps more so. Potentiality must be different from actuality; yet the two must be intimately related. I can’t tell you how potentiality differs from actuality because of its obscurity, but it evidently does differ, dramatically so. (Or else actuality is merely the way potentiality looks to our senses and doesn’t go deep ontologically speaking.[3])

Would other things become clearer if we had a better grip on causation? Anything in which causation directly figures would be—laws of nature, the origin of the universe, the operation of fundamental particles. But it might also help with the mind-body problem and the free will problem: How is the mind caused by the brain? How are free actions caused? Certainly this is an enormous gap in our understanding of nature, what with the ubiquity of causation, but a gap there seems little prospect of filling. The water may remain forever muddy.[4]


[1]I will be accepting the “skeptical realist” view of Hume in what follows, according to which causal powers are real existences that defy our limited understanding, not the positivist interpretation of Hume according to which the concept of causal power is incoherent and should be rejected.

[2]I am alluding to Wittgenstein’s discussion of meaning and use in Philosophical Investigations. He explicitly connects this issue to that of causal powers in the sections on machines (193, 194).

[3]Such a view is suggested by the thesis that all properties consistof causal powers. Then there is nothing to nature butpowers.

[4]This essay is intended to reflect the inadequacy of our understanding of causation, containing little in the way of genuine illumination. But perhaps it serves to scratch the depths.


One Hand Roll

Years ago I went to a concert by Buddy Rich. It began with the lights down and Buddy playing a drum roll–nothing surprising there. When the lights came up it was revealed that he was playing it with only his left hand! Much amazement from the audience. In the intervening years (about 45) I have doubted my memory of this feat, so astounding did it seem. I went on youtube yesterday to see if I could see any film of the great drummer performing this trick; and yes they have film of him doing it, along with other fancy things with right hand and feet. Not only that there were videos offering to teach you how to do the same trick yourself (it mainly involves deft use of the index finger to rebound the stick quickly off the bounce). I started practicing it: it’s certainly not easy but I can now see how it is physically possible. I wonder if I will master it at this late stage of my drumming career. I felt both disappointed and elated by this discovery.


Sensations Objectified



Seeing Sensations



It has been generally accepted that you can’t know what a sensation is like without experiencing it yourself. No experience of pain, no understanding of pain; no seeing of red, no knowing what seeing of red is. Possessing the concept requires instantiating what it is a concept of. This is not true of states designated physical: you can know what measles is without having it, or how a bat’s wing is constructed without having one, or what C-fibers are without having any in your brain. So sensations differ from physical states in this epistemic respect: sensations require having them to know them, but physical states can be known whether you have them or not. But why is this? What is it that makes it the case that there is this epistemic asymmetry? Why is it that I can know what C-fibers are without having any C-fibers but I can’t know what pain is without being in pain (at some time)?

The answer is crushingly obvious: I can seeC-fibers in someone’s brain (perhaps using a microscope), so forming the concept; but I can’t see pain in someone’s brain (with any microscope), so forming the concept. Lacking sensory perception of pain, I have to fall back on acquaintance with instances of it in my own person (I can’t be aware of pain in another person in this way). I have to get the concepts from somewhere, and perception (mainly vision) allows me to get the concept of C-fibers by looking inside brains (or things similar to brains), while the concept of pain cannot be acquired in that way, but must be based on introspection.[1]I can only introspect myself, but I can perceive many things other than myself. Thus it appears that we can assert the following counterfactual: If we could see sensations, we would know what they are without ourselves needing to have them. Suppose I couldn’t see C-fibers or anything like them, or sense them in any other way: then I wouldn’t know what C-fibers are—they would be like an exotic species I’ve never set eyes on (or heard about from someone who had). They would be an epistemic blank to me. That is our position with respect to sensations: we have never seen bat experiences, for example. Nor have we ever seen our own sensations, but here we have direct acquaintance with them in acts of introspection—as we don’t for bat sensations. But ifwe could see sensations–as they intrinsically are, as we see physical things–thenwe would not need to fall back on introspection. The trouble is that this counterfactual looks like it has an impossible antecedent: we necessarilycan’t see sensations. This necessity claim is very strong, and even if true applies only to human beings. Is it true that no possiblebeing could conceivably perceive sensations? It is not as if sensations lack causal powers or spatiotemporal coordinates—why should they not be in principle perceivable? And yet it is hard for us to conceive of what perceiving them might be like. That might just be a limitation on the human imagination, born of our particular cognitive faculties; maybe there are logically possible sensory systems that can respond to sensations as ours respond to streaks of lightning or cold air. But even if this is not possible the counterfactual still holds, only now with an impossible antecedent: if  (per impossibile) we could see sensations, then we would know what they are in that way. So this is still the explanation of why we can form concepts of physical states, but not of sensations, without having them: the reasonfor the asymmetry is that one is perceptible and the other is not.

Consider a character, Billy, suspended in a tank under conditions of sensory deprivation: suppose Billy has many bodily sensations but no perception of outer objects; in particular, he feels pain but has never seen a brain or anything like one. He knows very well what pain is, since he feels it every day, but he has no idea what C-fibers are, having never seen any, or anything like them. He is an expert phenomenologist but a physical ignoramus. One day he is liberated from his tank and given outer senses: a brain is placed before him with C-fibers prominently displayed and he gazes at it for a good long time. Now he knows what C-fibers are, not having known this before, even though he knew very well what pain is: he has learned something new. Therefore C-fiber firing is not reducible to (identical with) pain: it is something over and above pain. We have thus proved that there is more to the world than sensations: it would not be plausible to maintain that C-fibers are nothing more than pain—or else Billy would have known about C-fibers just by knowing about pain.[2]Whether or not this argument reaches its conclusion, it illustrates the dependence of certain concepts on perception: these concepts cannot be derived from introspection alone. The reason for Billy’s earlier ignorance about the nature of C-fibers is that he lacked perception of them; and the same can be said for our ignorance of (say) the sensations of bats—we lack perception of them. We only know the nature of our own sensations because we have another route to such knowledge, i.e. introspection. If we lacked introspection, we would have no concept of our own sensations either.

What if we could know both things both ways? Suppose we could know sensations from our own case andknow them via perception: then we wouldn’t have any problems of conceptual limitation vis-à-vis other types of experience. We could know what it’s like to be a bat without having bat-type experiences. This would open up our knowledge of mind considerably; maybe it would enable us to solve the mind-body problem, by locating the psychological in the realm of perceptible things.[3]It would certainly involve a conceptual transformation. Similarly, suppose that we could know physical states by perception andknow them by introspection: then a lack of perception of them wouldn’t bar us from arriving at an accurate conception of what they are (unlike Billy). One might have a sensation as of one’s C-fibers firing (not the same as a sensation of pain); and this too might contribute to solving the mind-body problem, by locating the brain in the field of consciousness. As it is, the duality of perception and introspection underscores the duality of physical and mental states, but that duality might reflect our epistemic predicament more than any underlying ontology. A perceptual concept for sensations would render sensations more objectively comprehensible, while an introspective concept for brain states would render them more subjectively comprehensible (someone who lacks the C-fiber sensation can’t know what it’s like to have that sensation). As it is, however, we are stuck with a sharp duality of understanding: one thing we understand perceptually, the other introspectively. We are thus saddled with an unbridgeable subjective-objective divide. The point I have wanted to make here is diagnostic: the reason for the divide is that we can’t see sensations. That may be a contingent truth or it may be a necessary truth, but it is why our concepts for sensations are as they are; if we conceived them perceptually, we would have no trouble extending our psychological understanding beyond our own case. Bat minds would be transparent to us—as transparent as their bodies and brains.  I strongly suspect that the limitation here is contingent, though human beings would have to change dramatically (unrecognizably) in order to become mind perceivers: I think there must be beings in possible worlds that can see (etc.) sensations. You just have to hook up a sensitive surface to the intricacies of sensations in such a way that the corresponding percepts reflect fine distinctions in the sensations perceived. In any case, that is the ground of the difference: we can see brains but we can’t see minds. Just think how much simpler your intellectual life would be if you could see both. The “world-knot” might unravel before your eyes, literally.


[1]I won’t discuss the possibility of having these concepts innately—say, being born with the concept of a bat’s experience (but no bat experiences). This raises other puzzles.

[2]Of course, I am alluding to Mary in her black and white room.

[3]For one thing, seeing sensations would allow us to draw picturesof them, as we can draw pictures of C-fibers. We could then set the pictures side by side and compare them. As it is, we can draw no picture of pain to compare with our picture of C-fibers. What would that do to the mind-body problem?



I am tired of hearing people say, as if it were uncontroversial, that they are “Humeans” about laws and causation, where they mean to defend the “regularity theory”. That was not Hume’s view, as has been amply demonstrated. They are claiming the authority of a great philosopher for a position he did not hold (in fact, I know of no great philosopher who held this view). What they are following is Ayer’s version of Hume not the real Hume. So they should declare themselves not Humeans but positivists. But that doesn’t sound so laudable since the fall of positivism. They should at least acknowledge that many people reject this version of Hume as well as the doctrine falsely attributed to him.



Have I mentioned that I have taken up harmonica? It’s a very enjoyable instrument. Little Walter and Sonny Boy Williamson are my heroes. I even play harmonica in a band, specializing in Hoochie Coochie Man and Long Train Running (the harp solo is extremely difficult to play). In the percussion department I have started doing djembe drumming after a lifetime of Western rhythms. This is all in addition to guitar and bass guitar. Oh the joys of retirement!

I’m also reading Jane Eyre, by which I am entranced. That wonderful old-fashioned writing, purity of heart, moral seriousness, and good old romance–also made possible by not being a professor any more. It provides an escape from the moral squalor of today. Highly recommended.



Objective Consciousness




Can There Be Subjective Facts?



I invite you, intrepid reader, to accompany me on a journey into the heart of darkness—into a region of utter obscurity. It will test us both, but it should be worth the effort, including the bouts of sickness and insanity. No, it won’t be that bad—just a bit of a headache and some mild nausea.[1]For I propose that we explore the question of whether reality could include facts that can only be grasped subjectively. By that last phrase I mean grasp that depends on occupying a particular point of view. The background is familiar from bats and blind people and alien forms of consciousness: we can’t grasp what it’s like to be a bat because we don’t share bat experience (we don’t occupy the bat’s “point of view”) and blind people can’t grasp the nature of color experience because they don’t have color experience (they don’t occupy the “point of view” of color perceivers). Some facts (properties, meanings) can be grasped without oneself instantiating them—for example, being an elephant or being a dodecahedron—but others (allegedly) can’t be grasped without being an instance of them oneself. You can’t know what it is like to see red without seeing red yourself, though there is no difficulty about knowing what a mountain is without oneself being a mountain. This suggests that there are subjective facts—facts that can only be grasped subjectively, i.e. from a specific point of view, i.e. by instantiating those facts oneself. It suggests that it is in the natureof certain facts that they can be apprehended only by beings equipped with specific types of experience, viz. those they are endeavoring to apprehend. Such facts might be called “intrinsically subjective”. By contrast, there are other facts that are “intrinsically objective”, i.e. they have a nature that allows them to be grasped from many points of view (or from nowhere). Thus some facts are subjective and some are objective, and this classification is written into them, part of their essence. The facts dictate the conditions of their being known (grasped, apprehended). My question is whether this is the right way to look at the matter.

Facts about consciousness are supposed the primary kind of subjective fact. If we define consciousness as consisting of the realm of facts there is something it is like to obtain, then we can say that facts about what states of consciousness are likeare subjective facts, i.e. they can only be grasped by sharing them. It will be convenient to introduce some abbreviations here, so let us call facts about what it is like “W-L facts” and let us call knowledge that depends on sharing the facts in question “S-I knowledge” (short for “self-instantiation-dependent knowledge”). Then we can say that W-L facts are intrinsically known in an S-I manner: that is, we can only grasp facts about what an experience is like by ourselves having experiences of that phenomenological type. In brief: W-L entails S-I. This is a move from the metaphysical to the epistemological: it is built into the nature of the facts (metaphysical) that they are grasped or known subjectively (epistemological). This thesis figures in an argument against materialism: mental facts can’t be physical facts because the former are S-I while the latter are not, i.e. the former are subjective while the latter are objective (understood in the epistemic way defined).[2]One response to this argument is to maintain that so-called objective facts are not as objective as you might think; in fact, they are subjective. This is because what we call the “physical” really consists of facts about consciousness, though consciousness of a primitive and alien type (I am talking about panpsychism and its spiritual cousins). The thought is that the problem of emergence can be solved by supposing that matter is shot through with mind, perhaps ismind at a fundamental level. That certainly looks like a promising strategy: straddle the mind-body gulf by edging the body in the direction of the mind. Mind arises from mind—not so inconceivable a feat. The point I want to make about this sort of approach is that it sharpens a more fundamental problem about consciousness, viz. how it is that consciousness has being at all. If reality consists of consciousness, and consciousness is W-L, and W-L requires S-I, then reality is intrinsically such as to be knowable only from a specific point of view. If the basic mental level of reality consisted of elementary consciousness of the type exemplified by bats, then only beings equipped with this type of consciousness could grasp the nature of reality. Reality would be intrinsically subjective in the sense that only certain types of being could have an adequate conception of it—and that could be a small subclass of the class of all possible knowing beings. Reality would (could) exist only forthis privileged class of being—for everyone else it would be strictly inconceivable. The question is whether that is intelligible: could reality consist of such essentially subjective facts, partially or totally? Could there be facts that could onlybe grasped from a particular point of view? Could there be facts that rule out any objective conception? Specifically, could W-L facts rule out a non-S-I mode of conception? In yet other words, could facts about consciousness resist any attempt to include them in an “absolute conception” of reality? Are they inconceivable objectively? My thesis will be that this is wrong—such facts cannot be intrinsically subjective. Facts about consciousness are not necessarilygrasped subjectively: even W-L facts must be graspable objectively. To put the point as strongly as possible, everythingabout consciousness must be conceivable objectively—and this is a fundamental metaphysical truth. There cannot, as a matter of metaphysical necessity, be purely subjective facts. There can be purely subjective conceptions, and we might well be confined to conceiving consciousness in this subjective way, but no fact(property, states of affairs) can be subjective in the intended sense. It is a category mistake to describe facts as subjective of objective; those appellations belong only to conceptions of facts—thoughts, representations, or ideas. The subjective-objective distinction is an epistemic distinction not an ontological one. But this leaves us in a very precarious position with respect to our understanding of what consciousness is, as will emerge.

First, let us note that experiences admit of several types of objective characterization drawn from within our current conceptual scheme. We can bring conscious experiences under causal descriptions (“the cause of this”, “the effect of that”), and we can express their relations with physical facts (such as correlated brain states). It is also possible to characterize them in abstract structural terms as well as mathematical terms (as in psychophysics). There is more to a conscious experience than what it is like for the subject: we can conceive such states in many different ways. The hard question is whether the W-L aspect can in principle be conceived in a way that doesn’t depend on sharing the point of view implicit in it. Is there a way of conceiving it that is available to beings that do not themselves instantiate the property in question? We naturally think of God here, but that raises questions it would be best to avoid (Does God instantiate all points of view? What is his knowledge like anyway?). One possibility is that this property exists but is completely ineffable (recall my warning about dark obscurity at the beginning): there are objective W-L facts, but no being could ever conceive them. All beings must conceive these facts subjectively or not conceive them at all: if the latter, then reality contains ineffable ingredients. A less alarming position is that possible beings might be able to grasp W-L facts without reliance on their own point of view: they might be able to form a conception that captures these facts and yet is independent of how they view things.[3]For example, they might be able to forge structural descriptions that encapsulate the facts and yet can be grasped by anyone whether they instantiate these facts or not. Then the nature of the facts would not dictateadopting a subjective conception of them; an objective conception would be available too. Of course, we find it hard to understand what such a conception would look like, given our own concept-forming faculties, but the general idea is intelligible enough—other beings (or us in the future) might be able to conceptualize consciousness in ways that transcend our current self-centered subjective conceptions. Then reality would not contain properties that can only be conceived subjectively; it would not be populated by properties that inherently favor one way of viewing the world over another.

Here it is important to make a distinction between two ways in which a fact might resist being conceived objectively. We have the modal truth: Necessarily it is impossible for us (fully) to conceive consciousness otherwise than subjectively. That truth might, however, have two possible sources: it might stem from the very nature of the fact in question—itdecides how it can be known; or it might be that ourfacultiesrestrict us to subjective conceptions—not the facts themselves. And we must not assume that just because we can’t conceive of W-L properties in objective terms that it is in the nature of those propertiesthat this is so—the reason might stem from our own cognitive make-up. Wenecessarily can’t conceive them in any other way, but theyimpose no restrictions on how they can be conceived; it is how we interact with them not what they are in themselves that gives rise to the necessity. It seemsto us that it is in the nature of color experiences to preclude a blind man from grasping them, but it may be that the difficulty arises rather from our distinctive human way of forming concepts of experience. Perhaps the blind man in other types of cognitive being has no trouble conceiving of experiences that he happens to lack. What is a necessary truth for us need not be true for everybody; in particular, it may not be the property itself that is the source of the problem. Thus the facts in question can be grasped objectively as a matter of principle even though we can never so grasp them. Then we would not have to admit that reality contains facts that are intrinsically tied to a specific point of view.

The general point here is that the terms “subjective” and “objective” are not descriptive of facts themselves but of ways of conceiving facts: no facts are subjective or objective considered in themselves. Physical facts can be conceived subjectively or objectively, relatively or absolutely, and the same is true of mental facts. If we are confined to subjective conceptions of mental states, that is a truth about us not about them: “subjective fact” is an oxymoron, unless it means “fact we happen to know about subjectively”. So consciousness exists neutrally between subjective and objective, despite our bias in conceiving it towards the subjective. But that means that we don’t grasp the manner of its existence: how we conceive it doesn’t tell us how it exists in reality, as an objective conception of it would. Thus we have an inadequate grasp of consciousness—in an important sense we don’t know what it is. What it is would be revealed from an objective standpoint, but that standpoint is inaccessible to us; we are limited to a standpoint that gives at best a partial conception of it. So we don’t understand what the existence of consciousness amounts to—what it isfor it to exist. That is the really hard problem: trying to figure out what we are talking about—trying to arrive at an adequate conception of consciousness itself. Even if we could solve the problem of emergence, say by invoking panpsychism, we would still be left with the more fundamental problem of discovering what the existence of consciousness really consists in. Granted, we know somethingabout consciousness, but we don’t know the most vital and basic thing—what its mode of existence is. We only grasp its existence-for-us not its existence tout court. It must, as a matter of metaphysical necessity, have an existence apart from our subjective mode of conceiving it, but we are blocked from discovering what this objective existence amounts to; at any rate, we presently have no conception of what it might be. This means, of course, that we don’t grasp the nature of our ownexperiences, let alone the bat’s, since they too must have an existence quaexperiences that is accessible from all points of view. We don’t grasp what it is like to be us(as that would be represented in an objective conception of what it is like to be us).

I have drawn a sharp line between two concepts: the concept of what an experience is like and the concept of a subjective conception. The former does not entail the latter: what it is like pertains to the nature of consciousness (its metaphysics) while the subjectivity of a conception pertains to how we think of a certain subject matter (epistemology). It is a substantive claim that the metaphysical property requires a subjective conception; and I have disputed this, suggesting instead that all facts must be accessible to an objective conception, even if not one of which we are capable. This logical point is lost if we carelessly use the world “subjective” to refer to a feature of consciousness itself andto the way we tend to conceive of it (by using our own case as model). Consciousness cannot be necessarilyconceivable only via a subjective conception, i.e. one that relies on self-instantiation, because that is an unintelligible idea of what reality is like. To repeat, reality cannot be relative to a particular point of view—only conceptions of reality can be. Facts are just facts: how we conceive them is another matter. This means that idealism cannot be restricted to how we now think of the mental: if the world is really the mind, then mental facts can’t be limited by the ways we generally conceive of them. Mental reality would have to be conceived objectively not subjectively, because its existence must be independent of the point of view a given type of creature brings to it. We may not be capable of acquiring the concepts needed to make sense of the objective existence of mental reality. At any rate, mental facts must have a nature that goes beyond what is contained in our present subjective conceptions. Those conceptions cannot even reveal what it is like to be a bat, though that latter fact is something that must be accessible in principle to different points of view. There must be a way of conceiving bat experiences that is accessible to beings that lack such experiences, on pain of making reality point-of-view-dependent. In other words, it is only a contingent fact that bat experiences can only be grasped by beings that share those experiences. There are no inherently subjective facts; subjectivity is in the eye of the beholder (which is not to say it is unreal).[4]


Colin McGinn





[1]Note to American readers: tongue is in cheek here.

[2]This argument is presented in Thomas Nagel’s “What is it like to be a Bat?” (1972), as is the general notion of subjective and objective I am working with.

[3]Nagel discusses the possibility (necessity) of objective descriptions of mental facts in The View From Nowhere(1986), chapter II.

[4]Of course there are subjective facts in other senses of the word: there are facts about conscious subjects, mental facts, facts about personal opinions.


Learning Language


A Model of Language Acquisition



Psycholinguists report that the child “internalizes” the grammar of his or her native language. Beginning with an innate schema of universal grammar (UG), the child hears the speech of adults and somehow extracts the rules that govern the particular language in question. That heard language is external to the child’s mind, but it becomes internalized as the language is gradually acquired. At some point the acquired language is externalized in the form of overt speech, as the child’s inner competence gets expressed by means of a sensorimotor system. We have internalization followed by externalization. But what kind of internalization is this—in what form is the outer language internalized? A natural answer is: memory. The child remembers what he or she has heard, suitably processed and generalized, and acquires the ability to speak by using these memories. Memories are internal, so that is the form the internalization takes: outer speech is internalized in the form of memories. The child possesses an innate internal UG combined with a memorized internal PG (particular grammar)—and also a lexicon of some sort, innate or acquired. Innate schema plus memory equals linguistic competence.

I want to enrich this picture somewhat. In addition to internal memories, I want to say that language acquisition involves inner speech: the child first learns how to speak inwardly, only subsequently expressing his or her linguistic mastery externally. So the internalization involves becoming a linguistic agent—a speaker. It is not just a matter of acquiring memories of what is heard, but also of acquiring an ability to engage in internal speech acts. Memory is presupposed in this, but it is not all that is going on internally. When outer speech develops inner speech is hooked up to a sensorimotor system, typically hearing and oral action (but in the deaf it can be vision and manual action). The child does not go directly from hearing a language and remembering it to being an agent of external speech; she takes the intermediate step of acquiring internal speech, a type of purely mental action. So the internalization consists of more than stored memories; it is full-blown internal linguistic agency. The external speech of others is internalized in the form of internal speech in oneself.

The psychological structure here may be compared to mental imagery. A person perceives an external object, forms a mental image corresponding to that perception, and then acts on the basis of the image (saying by drawing a picture of the imaged object from memory). This involves an extra step beyond merely perceiving an object and acting on the perception: an additional psychological layer is introduced. It is apt to describe the process of image formation as a type of internalization: an external object is internalized in the form of an image (not just a perception). The internal image acts as a kind of replica of the external object. Likewise, someone may hear a piece of music and retain the tune in memory, rehearsing it in her mind silently: this is not just storing the tune in memory, but also actively engaging in musical performance internally. We can think of this as inner musical action analogous to outward musical action like singing or playing an instrument. Learning to sing or play an instrument will typically involve developing the ability to perform inwardly—inner musicianship, we might say. You don’t just hear the violin with your ears and then play it outwardly; you also hear it inwardly and rehearse inwardly. You have internalized the (sound of the) violin. If someone lacked the ability to perform inwardly, they would presumably lack something important to learning the instrument. We might say that “musical imagination” is an important (essential?) component of musical ability. Imagination is “subject to the will” (as Wittgenstein says) and musical imagery is as willed as other forms of imagery. You can whistle with your mouth or you can whistle in your head. And there are other forms of internalization that proceed in much the same way—for example, internalizing a set of moral commands. It isn’t just that the child hears the moral commands of adults and commits them to memory, thus acquiring moral competence. He or she also incorporates these commands into an internal moral system—commonly known as conscience. Freud took the superego to consist of internalized parental commands—telling the child what to do and not do. This was taken to be essential to moral development: not just remembering what others have commanded but also commanding oneself—the “voice of conscience”. Whether Freud was right about the details doesn’t matter: what is important is that moral development involves the internalization of moral prescriptions—you tell yourself what to do (a form of inner speech). So: imagery, music, and morals incorporate this kind of strong internalization–as well as language. They are not like merely memorizing the dates of battles or the capitals of countries, because they involve inner action analogous to outer action. In particular, language acquisition goes through a stage of acquiring a highly structured set of internal abilities generating inner speech acts. Conceivably it might stop at that point, never progressing to the next stage of acquiring an ability to communicate—a language dedicated purely to thought. Language acquisition is not just a matter of stimulus-memory-response, but of stimulus-memory-inner action-response. To put it baldly, the child primarily acquires inner speech, which may or may not lead to outer speech.

This is an empirical hypothesis. I don’t know if it is true of actual human children. It certainly could be true of logically possible children, and it fits with the fact that children do acquire both inner and outer speech. Investigators would have to examine language development to see whether there is evidence that inner speech is acquired before outer speech. That might not be so easy to determine, given that inner speech is silent and invisible. But we could observe whether the child engages in self-directed monologue or shows signs of internal contemplation. Perhaps such investigations have already been undertaken: I am merely suggesting a plausible-sounding model that might or might not receive empirical confirmation. What I do think is that such a model would fall foul of traditional behaviorist prejudices and so might not be taken as seriously as it should; and also that it fits a general conception of learning that has many merits—the idea of learning as internalization in a strong sense. I gave several examples where such internalization operates and the case of language seems a natural addition to the list. The alternatives to the hypothesis are that inner speech develops in tandem with outer speech, but does not precede or enable outer speech; or that inner speech is the internalization of the child’s own outer speech.  Obviously these are empirical questions, but the hypothesis I offer seems to me antecedently at least as plausible as the others: inner speech is the mechanismwhereby outer speech develops, not merely something additional to it or the result of it. For it provides a psychologically natural way to construct linguistic competence: first master language internally without worrying about how it will be publically expressed, and only then search for a way to link linguistic competence with the body—whether the mouth or the hands, the ears or the eyes. For example, if you are mute but not deaf, you will naturally acquire a language by internalizing what you hear, but you will not externalize it by using your mouth. The ability to engage in communicative speech goes significantly beyond merely mastering grammar and vocabulary, which can be done purely inwardly. I imagine the child hearing outer speech, rehearsing it in his head, acquiring the ability to form internal linguistic strings, playing with these strings inwardly, and only later wondering how best to express his burgeoning thoughts to others.

This picture fits well the idea of language as primarily a vehicle of thought not communication. If language is mainly a medium of thought, its natural form of existence is as an internal symbolic system, silent and solitary; no need to recruit bodily organs that can produce externally observable signals to others. So the child first internalizes outer speech to aid it in cognitive processes—employing a language of thought—and then uses what has been so acquired to lever external communicative speech into existence. First we have symbolic thinking, then symbolic communication—the inner as the foundation of the outer. UG is already internal and intrinsically unconnected to communication; so PG can occupy the same psychological territory—an internal system dedicated initially to thought. Silent speech is the natural medium for thought, so it develops first; only subsequently do noise and gesture enter the picture to permit language to be used for speaking to others. The larynx is very much a Johnny-come-lately. The speech centers of the brain make contact with the larynx late in the game, and might not make contact with it at all. After all, if people had no use for communication, they would still need a language to express their thoughts inwardly: a language of thought has a point even if a language of communication does not. Granted that language enhances thought, silent speech is the way to go, the noisy kind being redundant if communication is not on the menu. You are going to need a language to enhance thought no matter what, so you might as well get that under your belt as soon as possible; how far you will need it for communication is a far more chancy affair and can be left as a secondary accomplishment.

Inner speech is certainly a reality of adult linguistic life. For solitary individuals it constitutes mostof linguistic life, and even for the very social it rumbles as ceaseless background chatter. It also mingles with outer speech in myriad ways. An interesting question is whether inner speech regularly precedes outer speech: do we first say it inwardly and then give it outward utterance? We (our brains) certainly plan what to say before engaging the larynx, constructing in silence a pre-formed string of words (often only milliseconds before the utterance). This is a form of inner speech, the production of symbolic strings independently of external manifestation, and it precedes external speech; so we can say that adult outer speech is subsequent to inner speech, expressing what existed antecedently. In the child language acquisition proceeds from inner to outer too, according to the hypothesis: outer spoken language externalizes a prior inner language. This is certainly contrary to the behaviorist assumptions of nearly all psychology (and philosophy) in the last hundred years, but being contrary to that tradition is surely a mark of truth in these more enlightened times.[1]The whole pointof the mind is that it cannot be observed; any theory of its achievements should respect that fact.


Colin McGinn

[1]The idea that the primary reality of language is its appearance in outer speech is shared by nearly all approaches to language in the last hundred years, but it is belied by the simple fact that inner speech is common and arguably basic. Language is essentially larynx-independent, sub-vocal not vocal.