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Philosophy E156: Philosophy of Mind. Week 11: Representationalism & Dennett’s Multiple Drafts Model of Consciousness. Theories of P-Consciousness. “ Inner Sense” View: “Higher Order Perception” Higher Order Thought View. Representationalism.
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Philosophy E156: Philosophy of Mind Week 11: Representationalism & Dennett’s Multiple Drafts Model of Consciousness
Theories of P-Consciousness • “Inner Sense” View: “Higher Order Perception” • Higher Order Thought View. • Representationalism. • Block argues that the first two sometimes result from a confusion of P-consciousness with something else, what he calls “monitoring consciousness”
The Representationalist Approach to Consciousness • The HOT Theory is a special case of the representationalist approach to consciousness. • Heil introduces the approach by considering the experience of a tree: • “Imagine that you are now looking at a stately gum tree. You are … undergoing a conscious visual experience of the tree. Now ask yourself, what are the qualities of this conscious experience?... [I]t would be a mistake to confuse qualities of an object you perceive with qualities of your experience of the object. The tree you happen to be looking at is 15 meters tall and green. Your perceptual experience of the tree is neither….” (Heil, p. 175)
Heil on the Phenomenological Fallacy • There is a natural confusion between the qualities of what’s observed and the qualities of the observation. • This is the basis of the “phenomenological fallacy” • Heil presents it this way: • “To run together qualities of what you experience with qualities of your experience is to commit the ‘phenomenological fallacy.’… The ease with which this fallacy is committed is arguably what lies behind the widespread belief that conscious qualities are profoundly mysterious. You describe your perceptual experience by describing what you are experiencing – what else could you do! You are experiencing something leafy and green. But nothing in your brain is leafy and green. So how could your perceptual experience be an occurrence in your brain?”
Naïve Realism • This fallacious reasoning has led many to embrace “naïve realism.” • Heil describes it this way: • “[I]n considering a perceptual experience, if you subtract the qualities of whatever is experienced … what is left? Whatever qualities remain would be qualities of the experience itself. And it is most unclear what these might be. Maybe experiences themselves altogether lack qualities. Or maybe, as the neorealists have it, what we call qualities of experiences are just qualities of what we are experiencing: when you ‘subtract the qualities of whatever is experienced’, nothing remains. Experiences of things collapse into the things experienced.”
The Representationalist Approach • This leads directly to the “representationalist approach.” • Heil describes it this way: • “Seizing on the point, a representationalist might contend that experiences themselves lack qualities of their own, qualities identifiable independently of the qualities of objects experienced: experiences are ‘transparent’. Or, more cautiously, although experiences could have qualities, these are not qualities you would be in any sense aware of in undergoing the experience. Representationalists hold that your consciously experiencing something is a matter of representing that thing: to be conscious is to represent.”
Representationalism Offers a Topic-Neutral Approach to Mind & Body • To representationalists, this approach offers an attractive way to reconcile mind & brain. • This is how Heil puts it: • “Now consider the qualities you represent the tree as having. Perhaps these qualities – or rather our representations of them – are enough to satisfy those who harp on qualia, self-proclaimed ‘qualia freaks’. If so, we would have uncovered a way of reconciling what are misleadingly called ‘qualities of conscious experience’ and materialism. A functionalist, for instance, could contend that qualities of experiences themselves are not present in ordinary awareness.”
The Representationalist Approach to Dreams and Hallucinations • The representationalist tries to handle dreams and hallacinations, Heil says, in a similar way: • “Perhaps your dreaming that you are fleeing a greenish alien or your hallucinating a greenish alien is just a matter of your representing the presence of a greenish alien. Your representation itself need not be greenish – any more than the words on this page that represent the alien are greenish. Indeed, in these cases, nothing at all need be greenish. Greenishness drops out of the picture.” (Heil, p. 177)
The HOT Approach is One Sort of Representationalism but Only One • The HOT Theory of Consciousness is representationalist in that it is essential, according to view, to be in a higher-order representational state in order to be conscious – namely, the state of representating oneself, by a thought, as being in some lower-order state • But another representationalist approach claims that the “lower-order properties of mental states are exhausted by their representational properties • One might (like Block) reject both the Inner Sense View and the HOT Theory, believing nothing “higher” is needed for P-consciousness • This is the representationalist position that interests Heil • Block attacks it by distinguishing A- from P-consciousness
Peacocke’s Anti-Representationalist Claim • “My claim,” Peacocke writes in the excerpt from Sense and Content I put online, “… will be that concepts of sensation are indispensible to the description of the nature of any experience.” • “This claim stands in opposition to the view that, while sensations may occur when a subject is asked to concentrate in a particular way on his own experience, or may occur as by-products of perception, they are not to be found in the mainstream of normal human experience, and certainly not in visual experience.”
Representational Content • The “representational content of a perceptual experience” is given by a proposition, or a set of propositions, which specifies the way the experience represents the world to be • A sensation (e.g., of smell) may have no representational content of any sort, though the sensation will be of a distinctive kind
Representational and Sensational Properties • Represensational properties will be properties that an experience has in virtue of its representational content • Sensational properties will be properties an experience has in virtue of some aspect – other than its representational content – of what it is like to have that experience
Peacocke’s Thesis and Its Opponents • “My aim,” Peacocke writes, “is just to argue that every experience has some sensational properties.” • “We can label those who dispute this view, and hold that all intrinsic properties of mature human visual experience are possessed in virtue of their representational content, ‘extreme perceptual theorists.’”
The Adequacy Thesis • The Adequacy Thesis (AT) “states that a complete intrinsic characterization of an experience can be given by embedding within an operator like ‘it visually appears to the subject that …’ some complex condition concerning physical objects. • “The ‘extreme perceptual theorist’ is committed to the AT.” • “For if the AT is false, there are intrinsic features of visual experience which are not captured by representational content.”
The Problem of the Additional Characterization • There are two trees, one a humdred yards from you, the other two hundred yards. • Your experience represents them as being of the same height and other dimensions. • Yet there is also some sense in which the nearer tree occupies more of your visual field than the more distant tree. • This is a challenge to the AT, since no veridical experience can represent one tree as larger than another and also as the same size.
Second Problem: What’s Omitted Can Vary While Representational Content is Held Constant • You look at pieces of furniture in front of you, first with one eye, then with both eyes. • The experience is different, and the difference is not captured by saying that with binocular vision some objects seem to be “in front of” others. • Thus there is experiential difference while representational content stays the same.
Julesz Random-Dot Stereogram • To construct a random-dot stereogram, you first place a bunch of dots randomly in an image. Then make two copies of it. In one copy shift a central square region to the left and in the other copy shift the same central square region to the right. This leaves holes in each of the images (left over from where the square shifted from). Fill the holes with new random dots. Why do you see it in 3D? The shift mimics differences which ordinarily exist between the views of genuine 3D objects. The extra dots (X and Y above) correspond to those parts of the background that one eye can see, but which are occluded from the view of the other eye by the foreground square.
Peacocke’s Analysis of the Random-Dot Cases • When viewed with two eyes, some dots are seen as being in front of others; when seen with only one eye, there is no impression of depth. • The difference between monocular and binocular vision is both sensational and representational.
Third Problem: Nonrepresentational Similarities among Experiences • Successive experiences, first seeing one face of the cube in front, then seeing another face of the cube in front, with different representational content. • However, there are further similarities beyond these representational differences. As Wittgenstein says, “I see that it has not changed.” • The AT cannot account for this fact.
Tye’s Reply to the First Problem • “The reason that the trees look different is that the experience represents the nearer tree as having a facing surface tha differs in its viewpoint-relative size from the facing surface of the further tree, even though it represents the trees as having the same viewpoint-independent size.” • “Perceptual experience represents the feature nonconceptually.” (Reply to the objection that the experience is had by people who lack the concept of a visual angle.)
Tye’s Reply to the Second Problem • “The claim I reject … is the claim that there is no representational difference.” • “When I view the situation with both eyes, I see a little more at the periphery of my visual field and there is an increase in how determinately my experience represents object depth.” • “An appeal to Qualia is not required.”
Tye’s Reply to the Third Problem • “The obvious response to this example [of the Necker square] is to concede the point that something in the experience remains the same but to explain this fact representationally by holding that both before and after the ‘aspect’ switch, the experience represents the cube as having various unchanging spatial properties relative to the given point of view….” • “[B]oth before and after the switch, side ABCD [lower left square] is represented as being lower than and somewhat to the left of the side EFGH [upper right square], side AEHD [left parallelogram] is represented as being level with and wholly to the left of side BFGC [right parallelogram,” etc.
The “First-Person-Plural Presumption” • I shall begin with Chap. 4 of CE, p. 67: “[J]ust about every author who has written about consciousness has made what we might call the first-person-plural assumption: • Whatever mysteries consciousness may hold, we (you, gentle reader, and I) may speak comfortably together about our mutual acquaintances, the things we both find in our streams of consciousness.” • To understand, think of the “inner sense” view • Analogy between sensing the outer world & sensing the inner world • But a way exists that “inner sense” disanalogous to “outer sense” • We can go wrong in Cartesian ways with “outer sense” but we are supposed to be immune to such error with “inner sense”
Descartes’s Version of the “First-Person-Plural Presumption” • Dennett derisively cites Descartes as an example: “Ever since Descartes and his ‘cogito ergo sum,’ this capacity of ours [introspection] has been seen as somehow immune to error” • What does Dennett mean? • He cannot literally mean Descartes’s “cogito ergo sum” argument alone • “I think, therefore, I am” – there is nothing here about the immunity to error of introspection • Descartes’s next step – He asks: What is it that makes the cogito argument possible? Descartes concludes it is that • (1) he is a thinking thing & that • (2) he knows the cogito & (1) “clearly and distinctly”
Descartes’s Commitment to Immunity from Error • Here it is Descartes makes his immunity move • He says that he had thought that he could not go wrong in his simple & basic knowledge of the world – that he knew it “clear & distinctly” • He concludes that he had confused • things themselves with • his ideas of things • He concludes that the does not have “clear & distinct knowledge” of the former (things) but only of the latter (ideas of things)
Descartes’s Distinction • Descartes makes this argument distinguishing what he lacks “clarity & distinctness” about (things) from what he has it about (ideas) in the Third Meditation, ¶3: • “I before received and admitted many things as wholly certain and manifest, which yet I afterward found to be doubtful. What, then, were those? They were the earth, the sky, the stars, and all the other objects which I was in the habit of perceiving by the senses. But what was it that I clearly [and distinctly] perceived in them? Nothing more than that the ideas and the thoughts of those objects were presented to my mind. And even now I do not deny that these ideas are found in my mind. But there was yet another thing which I affirmed, and which, from having been accustomed to believe it, I thought I clearly perceived, although, in truth, I did not perceive it at all; I mean the existence of objects external to me, from which those ideas proceeded, and to which they had a perfect resemblance; and it was here I was mistaken, or if I judged correctly, this assuredly was not to be traced to the force of my perception.”
Caveats • Descartes is an ongoing target of Dennett’s in CE • But Dennett ignores some important nuances • For example, two caveats on immunity from error: • In next paragraph of the 3rd Meditation, Descartes sees that he can imagine going wrong in areas (math) that he thought clear & distinct – • God perhaps created Descartes so imperfectly he cannot reliably do simple math • same problem exists for everything else, including introspection • Likewise, in Discourse on Method Descartes argues that error is possible in introspection due to the distinctness of sensation & belief about sensation – which can come apart
Descartes’s Solution • This then creates a new skeptical problem for Descartes – the possibility of going wrong about inner sense – of never knowing • His skeptical problem overlooked by Descartes’s opponents • Descartes’s solution: to argue that skepticism and theism are incompatible • (1) God exists, • (2) God is Descartes’s creator, • (3) Descartes’s going wrong these ways would make God a deceiver, • (4) God’s being a deceiver inconsistent with God’s nature • Still, Descartes’s solution would not be attractive to opponents • Some would argue functionalism & skepticism incompatible
Cartesian “Privileged Access” & the “First-Person-Plural Presumption” • Privileged access: Descartes, like most people, would say that each of us has privileged access to the content of his experience • Even Dennett agrees • But Dennett also says that “we tend to think that we are much more immune to error than we are” • No infallibility, no incorrigibility • He gives the example of holding a playing card at the periphery of vision & being unable to identify the color
Heterophenomenology • Dennett rejects commitment to the first-person-plural presumption, because he thinks that there is no guarantee of privileged access, either of the existence of what’s perceived or of the character of it • Because of this, we cannot do science without a different approach • This leads him to the heterophenomenological method – listening to what subjects say about their phenomenology and drawing inferences
The Intentional Stance • Recall Dennett’s approach to the mind-body problem – “the intentional stance” • Instrumentalist – matter of how we usefully see ourselves • Talk of mental states is talk of states that we regard ourselves and other creatures as having in order to make sense of their pursuing ends • Talk of phenomenology is regarded this way • On pp. 76-7 of Consciousness Explained he writes:
Zombies, Philosophical and Otherwise • A zombie, according to urban legends around Haitian voodoo, is a person who has been put under a spell and deprived of free will – a member of the “living dead” • Philosophers appropriate the term to refer to creatures just like you and me – literally just like – except for one thing – lacking in the inner light of consciousness • One way to generate a philosophical problem of consciousness is to ask if zombies are possible in any way and if so why we aren’t zombies
Heterophenomenological Account of Humans & Zombies • One virtue of the heterophenomenological approach to consciousness is to evade the question about zombies • The heterophenomenologist takes the creature’s words the same whether or not it is a really conscious being or a zombie duplicate • Some would say this is a flaw in the method • Dennett thinks we can’t do science without it
Heterophenomenological Worlds • A “heterophenomenological world” is the fictional world that is most useful according to the intentional stance to attribute to the subject given the subject’s words: • “[O]ur experimenter, the heterophenomenologist, lets the subject’s text constitute that subject’s hetero-phenomenological world, a world determined by fiat by the text (as interpreted) and indeterminate beyond. • “This permits the heterophenomenologist to postpone the knotty problems about what the relation might be between that (fictional) world and the real world.”
Cartesian Materalism • Descartes believed not only in dualism, that we are made up of both brain and soul, but that there was a point in the brain where everything came together before it was sent across a psychophysical bridge into the soul • He located that point in the pineal gland, located between the two hemispheres • Dennett ridicules the non-dualist vestige of such a view as “Cartesian materialism” (CE, p. 107): • “the view you arrive at when you discard Descartes’s dualism but fail to discard the imagery of a central (but material) Theater where ‘it all comes together’”
The Cartesian Theater • “The Cartesian Theater is a metaphorical picture of how conscious experience must sit in the brain. • “It seems at first to be an innocuous extrapolation of the familiar and undeniable fact that for everyday, macroscopic time intervals, we can indeed order events into the two categories ‘not yet observed’ and ‘already observed.’ • “We do this by locating the observer at a point and plotting the motions of the vehicles of information relative to that point.”
Problem with the Cartesian Theater Metaphor • “But when we try to extend this method to explain phenomena involving very short time intervals, we encounter a logical difficulty: • If the ‘point’ of view of the observer must be smeared over a rather large volume in the observer’s brain, the observer’s own subjective sense of sequence and simultaneity must be determined by something other than ‘order of arrival,’ since order of arrival is incompletely defined until the relevant destination is specified.”
Three Puzzle Cases • Nelson Goodman’s & Paul Kolers’ “color phi” experiment • Geldard & Sherrick’s “cutaneous rabbit” experiment • Benjamin Libet’s “backward referral in time” cases
Phi Phenomenon • http://upload.wikimedia.org/wikipedia/commons/6/6e/Lilac-Chaser.gif
Color Phi Demonstration • http://www.philosophy.uncc.edu/faculty/phi/Phi_Color2.html