Brain Views

Oh, those perishing bats, hogging all the limelight, with their fancy sense of echolocation! Let’s talk about the humble human and how things look to him or her. Can this be reduced to brain states? We have agreed that consciousness is having a point of view, specifically a visual one; can we argue that this point of view cannot be merely physical? Can we formulate an anti-physicalist argument based around the notion of a visual point of view? And is this helpful? Yes, we can, and yes, I think it’s a helpful to do so. The argument is very intuitive when framed this way. Suppose you are sitting across from me, with a different visual perspective; and suppose I can see your brain, specifically what is happening in your visual cortex. I see the physical correlate of your visual experience, but I don’t see your visual experience—I have to imagine that. I don’t use my imagination to know about your brain state, but I have to use it to know about your conscious state. So, how can the two things be identical? I might find it difficult to fire up my imagination in order to obtain this knowledge—it takes some effort. If I am very unimaginative, I might fail. But I don’t need to make any effort in order to know what is happening in your brain—I can just look and see (it might be recorded up on a screen or actually open to view). My view of your brain is unimpeded, but I have no view of your view, only an act of imagination. The brain is in its nature something open to visual inspection, but your visual experience is not; it is not perceptible at all, being (as we say) private. You can’t view a view.

This is a mild example of epistemic difficulty; most people have no trouble imagining the other person’s perspective (but do they know it as well as the person who has that perspective?). Imagination can provide knowledge of other minds. But notoriously, it will only take you so far: can a person with impaired vision imagine the vision of someone visually unimpaired, or a color-blind person imagine the vision of someone not color-blind, or a bat imagine the vision of an eagle, or a human imagine the vision of a fly, or a human imagine the vision of a visually superior alien, or even of a bee? Imagination is a frail reed when it comes to knowing the nature of visual experience in general—and why should be it be omniscient in this respect? But this limitation is irrelevant to knowledge of the brain; here we can just look and see—we can inspect the brain to our heart’s content. It puts up no resistance; it doesn’t run and hide; it is quite open about what is in there. It can be viewed from afar or up close or under a microscope. But visual experience can’t be viewed at all and must be conjectured based on imagination or projection or surmise. The mind is private by nature and the brain is public to a fault (introvert and extravert, respectively). Suppose the difference between my brain and yours is that I have neurons that fire with greater frequency than yours do, or my neurons have longer axons; and suppose this is the physical basis of the difference in the way we see things, say colors. In such a case I have absolutely no difficulty knowing the physical difference between us, but I face an opaque wall when it comes to knowing your visual experiences, supposing these to be very different from mine. Your experience is closed to me but your brain is an open book. And this is part of the essence of experience and the brain: the brain is inherently knowable in a certain way, but the mind is inherently not knowable in that way. To be conscious is to have a point of view, but points of view can’t be viewed, while brains can be. Thus, I can form a conception of your brain by perception, but I can’t do that with your mind; I can’t perceive your perceptions. My consciousness cannot be a consciousness of your consciousness—my point of view can’t take in your point of view as direct object. Views can’t be viewed. Simple as that.

This is really just another way to state the bat argument or the “knowledge argument”. But it is extremely simple and requires no elaborate thought experiments or alien beasts. It requires only the simple idea that points of view can’t be viewed: you can’t look at what someone else is experiencing; you can’t have an experience as of an experience. If you could, there would be no limitation on our knowledge of other minds deriving from differences in how we experience the world. Everyone would know what anyone else is experiencing just by looking at their brain (or face): visible brains (or faces) would produce knowable minds. Indeed, to see a brain would be exactly the same experience as seeing a mind, but it isn’t. There would be no other minds problem, but there is. There would be no ignorance of an alien creature’s experience, but there is. It follows that mind cannot be identified with brain. The root cause is privacy; or rather, mental privacy combined with brain publicity. For if the brain were as private as the mind, there would be no epistemic discrepancy. This is really the thrust of the standard argument, though it may be obscured by standard presentations. Just remember: you can’t view a view, but you can view a non-view (like the physical brain). This is why you can’t know alien experience but you can know alien brains. Brains cause themselves to be seen, but minds don’t cause themselves to be seen. It would not be possible to start with not seeing someone else’s mental state (as such) and then gradually home in on it till you see it in the form of a brain state. Nor would it be possible to start with a seen brain state and gradually alter the viewing conditions until it vanished into a mental state. But you could begin by seeing water in the normal way and gradually magnify it till the H2O molecules became visible, or begin with the molecules and pull back till you saw the watery liquid as you normally see it. You cannot see a mental state as a brain state or a brain state as a mental state.[1]

[1] The problem with the bat is that we can’t see its echolocation experiences; if we could, we would be able to form a conception of them. But then, there would be no argument to the effect that one can be known and the other not known. However, the imperceptibility point immediately shows that mind and brain cannot be identical (short of a convincing rebuttal). That is the underlying mechanics of the argument. Other minds must be imagined, since they cannot be perceived; but brains can always be perceived, so there is no need to imagine them.

‘Against Identity Theories’, “The Deep Problem’ and the ‘is’ of definition

I agree with the gist of both papers. However….

Aristotle distinguished ‘real’ from ‘nominal’ definition.  The latter is just a way of identifying what a name names.  So (to modify and build on an actual Aristotelian example)  “‘Lightening’ names the flashes in the sky often visible during a violent rainstorm”  is a nominal definition, ‘lightening is an electrical discharge from cloud to cloud or cloud to earth’ would be a real definition.  Similarly, ‘“Thunder’’ is the sound often heard during heavy rainstorms’ is nominal, ‘Thunder is an electrical…etc’ is ‘real’.  A real definition says of the thing defined ‘what it is’, its essence.  If thunder and lightening share an essence, they are identical. They are, so to speak, the same embodied form (or ‘act’ of an embodied form) that can be both seen and heard. ‘A thing and its real essence are one and the same’ is an Aristotelian principle that Locke appeals to in his argument that all our (incl. Aristotelian) definitions of substances are nominal.  We don’t (or didn’t when Locke wrote) know the underlying nature of any of them (and Aristotelians were further away from knowing it than atomists).

Is the natural inclination to reject the view that the essence of thought is a certain kind of  neurological process–that that is ‘what it is’–significantly different from the natural inclination to reject the view that thunder and lightening are the same thing?  We might try to distinguish the latter two by proposing that lightening is not an electrical discharge, but the stream of photons generated by one, and that thunder is the sound waves. ..etc., but that is unconvincing as compared with what seems a straightforward indication of different modes of presentation, by adding ‘as seen’ and ‘as heard’ respectively. We also experience, and think of, both lightening and thunder as distant or near, out there happening in the sky.  Perhaps without realising it, we are seeing and hearing the same event.

  So one might characterise sense experience and thought as a neurological process ‘from the inside’, or ‘as lived’, as opposed to ‘as observed and recorded by neurophysiologists’.  It isn’t even necessary to bring neurophysiology into it.  Long before any such understanding of the kind of physical process it is that goes on animals’ brains, it was judged that the brain is an organ with a function, and there was speculation as to what its function is (cooling the blood was an early candidate, if I remember right). So it was possible to achieve an untheoretical or minimally theoretical reference to the physical processes going on in a living brain, and speculate that they are the functioning of the organ of sensation, perception, memory and thought. 

Why, then, is it that  ‘We don’t normally say “H2O is water” or “molecular motion is heat” or… “brain processes are sensations” …[or] “C-fiber firing is pain”)’? Presumably  ‘normally’ here just means ‘generally’.   ‘Nominal definition’ will generally come before ‘real definition’.  We commonly have ways of identifying and picking out kinds of things, events and processes before we come to understand their nature.  Sometimes, on the other hand, theoretical explanations will promote principled re-conceptions of the everyday. In any case a student (or examiner) might ask ‘What is H20?’, or ‘What is C-fibre firing?’ (or, looking at an MRI scan, ‘What is that process?’), questions with ‘Water’ and ‘Pain’ as appropriate answers (although ‘It’s what happens in the brain when the subject is in pain’ might be a less crude response to the latter.)   

Consciousness is certainly a special case, since there’s something, as it seems intrinsically, mysterious about how evolution came up with that useful attribute, or how the physical universe originally contained the potentiality for it. That problem doesn’t seem to be enough to undermine the thought that, in asking someone whether they are in pain when observing their C-fibres firing (however that is done), we are dealing with one and the same process. It is, however, a problem merely ignored or brushed aside in the crude, reductively materialist thought that experience and thought are ‘nothing but’ brain processes.  

The main, surely correct point made in ‘Against Identity Theories’ and, more directly, in ‘The Deep Problem’, can perhaps be put in quasi-Aristotelian terms.  For Aristotle, the real definition of a kind of thing, one that gives its essence, explains its other ‘properties’ (ie attributes possessed by everything of that kind).  So one might say that the fact that water is H2O explains the properties of water, and the capacity of chemical theory to explain and predict the properties and interactions of more or less familiar stuffs (not to speak of the possibility of so far unobserved elements) is a measure of its adequacy.  Neurophysiology isn’t like that.  It is, and seems doomed to be, too much a matter of correlation to be in that way theoretical.  However well the process going on in the nervous system is understood in physical terms, and however closely it is correlated by empirical psychologists with the process of experience and thought, it’s not going to explain ‘what it is’ to be in pain.   The ‘identity thesis’ might tell us something about where mentality fits into the physical world, but it doesn’t offer an explanation of what it is.   

Non-Perceptual Knowledge

Perceptual knowledge is quite sharply limited, though clearly a type of knowledge. But we don’t customarily stop there; we generally extend the concept of knowledge beyond this restricted domain, well beyond it. Thus, we recognize several kinds of inferential knowledge—knowledge about things we don’t and can’t perceive. Are there any reasons to doubt this extension, stopping short of invoking extreme skepticism. Is the concept of knowledge inherently resistant to such epistemic promiscuity? Given that this “secondary knowledge” is not perceptual, we cannot locate its vehicle in sensory experience, so we will need some other psychological vehicle. This has various names: belief, judgment, opinion, surmise, conjecture, supposition, postulation, hypothesis, etc. Then we will be saying that some knowledge is grounded in this kind of state: for example, some knowledge is a type of belief (though many beliefs are not knowledge). In this way we take in knowledge of other minds, the past, the future, remote parts of the universe, the fine structure of matter, and so on. We don’t perceive these things but we do have beliefs about them. This has the consequence, obviously, that knowledge and belief are compatible states; as Plato would put it, some “opinions” (not all) count as instances of knowledge. The state of mind of knowing is compatible with the state of mind of having an opinion or surmising or conjecturing. But Plato would have none of that; for him, knowledge and belief (etc.) exclude each other. It is impossible to believe and know the same thing at the same time. And ordinary language would appear to back him up: no one in his right mind would say “I know that p and I am also of the opinion that p”, since the second conjunct contradicts the first. The well-educated analytical philosopher has his riposte ready—“That’s just a conversational implicature, my friend!” End of discussion. But is it just an implicature? Isn’t there something right in the idea that knowing is not compatible with believing? Don’t I need to do more than conjecture in order to know? I have to be convinced. Suppose I form a belief irrationally, based on my whims and wishes; but the belief happens to be true and I have gathered evidence sufficient to support my belief. However, I don’t hold the belief because of the evidence but because of my wishes: do I then have knowledge? Surely, I am in the wrong state of mind. The trouble is that beliefs and opinions can be held for irrational reasons, so they are unsuitable as the psychological basis of knowledge (the same is not true of sense experiences). Beliefs are often irrational, easily manipulated, and prone to error; so, we don’t want to involve them in the serious business of possessing knowledge. They also allow people to go out on a limb, get fooled by conspiracy theories, make mistakes of reasoning. Beliefs are just not a good way to run your cognitive life. You would be better off without them. They are an epistemic trap.

Many serious philosophers have advocated just that. Stick to what you really know, what you have seen with your own eyes, don’t believe other people with all their lies and bullshit. Remain agnostic about matters you really know nothing directly about. Don’t believe. Don’t form wacky opinions. You can behave as if you believe; you can provisionally entertain and act upon certain propositions; you can hold that a proposition has not yet been falsified; you can pretend the proposition is true: but for heaven’s sake don’t believe things of which you have no direct experience! That way error lies, if not madness. Don’t believe what you don’t directly know, and if you do directly know it you needn’t believe it. Abolish belief altogether! That would appear to be Plato’s view, and Popper’s too. Things will be much clearer and cleaner that way, once you have adopted the zero-belief lifestyle (“Just say no to belief!”). It might be replied that this is too sweeping: surely some beliefs are better than others, some opinions better informed than others. That is clearly correct, but it doesn’t blunt the force of the Plato-Popper position. We can register the necessary distinctions without employing the concept of knowledge so loosely and irresponsibly; we can simply talk of degrees of justification, warrant, cognitive virtue. Nor need we recommend any linguistic revision in our ordinary use of “know”; we just need to recognize that it is not literally true, a figure of speech, a useful convenience. We should stop thinking that we really know in these cases, whether in the primary sense or a secondary sense. We should stop assimilating these cases to the basic cases provided by perceptual knowledge—the only true knowledge. In fact, it is not clear that anyone is fooled by our common use of “know”: people are aware that this is so much loose talk—like talk of the sun rising. When I ask people about this, they generally say that of course we don’t really know other minds no matter what words we utter. Some propositions have higher epistemic credentials than others, that’s all; not much is really known. The language game involving “know” is just that—a game, not to be taken too seriously and literally.

It might be asked how this game came into being—why did we start using “know” so promiscuously? My theory is that it came from religion and then migrated into science. Clearly, it is not possible to perceive God, but religion encourages us to believe in him; so, it needs a notion of knowledge compatible with imperceptibility. Thus, belief (“faith”) was introduced as the route to knowledge of God. Religion needs a belief-based epistemology conducive to (non-perceptual) knowledge. Science, especially astronomy, needs a similar epistemological structure: belief as the vehicle of scientific knowledge. We need to stretch the concept of knowledge if we are to make room for scientific knowledge, thus conferring on it the honorific status of knowledge proper. However, there is really no pressing need to stretch the concept this far, to the breaking point as it were; we can settle for something short of knowledge, such as pragmatic acceptance. Then we avoid introducing an untenable dualism into our epistemology—between perceptual knowledge (the real deal) and something far removed from it (and not clearly knowledge at all). We don’t need to mess with the concept of knowledge, stipulating knowledge where it does not belong. There is simply a lot we don’t know (primary!), even when the relevant science is as good as it can be (pretty damn good). It is pointlessly provocative to insist that we know Darwin’s theory to be true, say, which invites the response “Have you seen it in action?” Epistemic merit is not the same as knowledge strictly so-called. The former is possible without the latter. Then we can say that only perceptual knowledge is really knowledge, bearing in mind that perception (“seeing”) is not just a matter of the physical senses. Unless we stick to this strict and sharp distinction, we end up completely confused about what counts as knowledge and what doesn’t. Opinions can differ in their epistemic credentials, but opinions are never knowledge, just as Plato maintained. Knowledge can be conceptualized as seeing in all cases, with no weakening contemplated. Belief therefore has nothing to do with knowledge proper: not perceptual knowledge and not some kind of dilution of that. Knowledge and belief are mutually exclusive. So far from knowledge implying belief, it implies non-belief. Knowledge is never true justified belief, or some improvement in that formula. All knowledge is acquaintance knowledge. The natural kind knowledgeis a single unified category not a congeries of different concepts. I would recommend the attitude of pragmatic acceptance for any truth claims that go beyond perception. There is no such thing as “inferential knowledge” or “testimony knowledge”. This is the way things should be carved up epistemologically, not into different types or degrees of knowledge.[1]

[1] How revisionary is this position? It is certainly revisionary of philosophical and scientific custom (not counting Popperians), but it is not clear that it contradicts the ordinary man’s tacit epistemology. From my informal surveys, people are quite ready to accept that nothing is really known beyond direct perception. It is deemed folly to suppose otherwise. This doesn’t prevent them from preferring some theories to others, quite rationally. People are surprisingly strict about the word “know”; they don’t like to see it bandied about. It is so in Barbados anyway (fine people).