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Philosophy E156: Philosophy of Mind Week Ten: Representationalist Theories of Consciousness
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Philosophy E156: Philosophy of Mind

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Philosophy E156: Philosophy of Mind. Week Ten: Representationalist Theories of Consciousness. Block’s Four Concepts of Consciousness. Phenomenal consciousness, or P-consciousness Access-consciousness, or A-consciousness Self-consciousness Monitoring consciousness. - PowerPoint PPT Presentation
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Page 1: Philosophy E156:  Philosophy of Mind

Philosophy E156: Philosophy of Mind

Week Ten: Representationalist Theories of

Consciousness

Page 2: Philosophy E156:  Philosophy of Mind

Block’s Four Concepts of Consciousness

• Phenomenal consciousness, or P-consciousness

• Access-consciousness, or A-consciousness• Self-consciousness• Monitoring consciousness

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How Block Characterizes Phenomenal Consciousness

• “Phenomenal consciousness is experience”• “[W]hat makes a state phenomenally conscious is that there is

something ‘it is like’ to be in that state”– [Identifying phenomenal consciousness with experience looks odd if

consciousness is the property a mental state has of being conscious, since it would not seem to be true that experience is a property of being conscious – we use the word “experience” differently]

• “I cannot define P-consciousness in any remotely non-circular way” – i.e., in any “reductive” way

• “[T]he best one can do for P-consciousness is in some respects worse than for many other things because really all one can do is point to the phenomenon”

• “[H]ow should we point to P-consciousness? … [V]ia rough synonyms [and] examples”

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How Block Characterizes Access Consciousness

• “A representation is A-conscious if it is broadcast for free use in reasoning and for direct ‘rational’ control of action (including reporting)”

• “An A-state is one that consists in having an A-representation”• “[P]ut crudely, … A-conscious content is representational”

– “It is of the essence of A-conscious content to play a role in reasoning, and only representational content can figure in reasoning”

• “[T]he paradigm A-conscious states are ‘propositional attitude’ states like thoughts, beliefs and desires…. (E.g., the thought that grass is green.)”

• “I see A-consciousness as a cluster concept in which – reportability is the element of the cluster that has the smallest weight – even though it is often the best practical guide to A-consciousness”

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Self-Consciousness• Block writes: “I mean the possession of the concept of the self and

the ability to use this concept in thinking about oneself”• Mirror behavior

– Chimps try to wipe off spots painted on their foreheads and ears– Monkeys do not– Neither do human babies until after 18 mos.– Dogs treat their mirror images as strangers, unlike higher primates

• If we take monkeys and dogs and young infants are thus lacking in self-consciousness, we do not correspondingly deny they have pain or deny there is something it is like for them to see themselves in the mirror– Thus P-consciousness differs from self-consciousness – animals might lack

the latter and have the former

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Block’s Concepts and Self-Consciousness

• We can infer that P-consciousness and A-consciousness are forms of state consciousness.

• However, it is unclear to me if the term “self-consciousness” is ever used by Block in a way that would make it an example of state consciousness.– Block defines it as “the possession of the concept of the self and the ability

to use this concept in thinking about oneself.”– The “possession of the concept of the self and the ability to use this

concept in thinking about oneself” would not seem to be a mental state, although it clearly involves mental states.

– People and higher primates seem to be self-conscious, not their mental states.

– But this would not seem to be creature consciousness, either – as Heil defines it.

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Sharpening the Concepts of P-Consciousness and A-Consciousness

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Sharpening the Concepts of P-Consciousness and A-Consciousness• Four differences:

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Sharpening the Concepts of P-Consciousness and A-Consciousness• Four differences:• P-conscious states phenomenal, A-conscious states

representational

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P-conscious states phenomenal, A-conscious states representational

• Block: “It is of the essence of A-conscious content to play a role in reasoning, and only representational content can figure in reasoning.”

• “The paradigm P-conscious states are sensations, whereas the paradigm A-conscious states are ‘propositional attitude’ states like thoughts, beliefs and desires, states with representational content expressed by ‘that’ clauses. (E.g. the thought that grass is green.)”

• “P-conscious contents can be representational. Consider a perceptual state of seeing a square. This state has a P-conscious content that represents something, a square….”

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Sharpening the Concepts of P-Consciousness and A-Consciousness• Four differences:• P-conscious states phenomenal, A-conscious states

representational

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Sharpening the Concepts of P-Consciousness and A-Consciousness• Four differences:• P-conscious states phenomenal, A-conscious states

representational• A-conscious states always transitive (states of consciousness

of or about), P-conscious states sometimes transitive, sometimes intransitive

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A-conscious states always transitive, P-conscious states sometimes transitive• “A-conscious states are necessarily transitive: A-

conscious states must always be states of consciousness of…. P-consciousness, as such, is not consciousness of” (my emphasis).

• “Consider [the] perceptual state of seeing a square…. It is a state of P-consciousness of the square even if it doesn't represent the square as a square, as would be the case if the perceptual state is a state of an animal that doesn't have the concept of a square. Since there can be P-consciousness of something, P-consciousness is not to be identified with intransitive consciousness.”

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Sharpening the Concepts of P-Consciousness and A-Consciousness• Four differences:• P-conscious states phenomenal, A-conscious states

representational• A-conscious states always transitive (states of consciousness

of or about), P-conscious states sometimes transitive, sometimes intransitive

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Sharpening the Concepts of P-Consciousness and A-Consciousness• Four differences:• P-conscious states phenomenal, A-conscious states

representational• A-conscious states always transitive (states of consciousness

of or about), P-conscious states sometimes transitive, sometimes intransitive

• A-consciousness is a functional notion, A-conscious content is system-relative; P-consciousness is not a functional notion and P-conscious content is not system-relative

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A-consciousness is a functional notion, P-consciousness is not

“In terms of Schacter's model of the mind (see the original version of this paper Block (1995)), content gets to be P-conscious because of what happens inside the P-consciousness module. But what makes content A-conscious is not anything that could go on inside a module, but rather informational relations among modules.”

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Sharpening the Concepts of P-Consciousness and A-Consciousness• Four differences:• P-conscious states phenomenal, A-conscious states

representational• A-conscious states always transitive (states of consciousness

of or about), P-conscious states sometimes transitive, sometimes intransitive

• A-consciousness is a functional notion, A-conscious content is system-relative; P-consciousness is not a functional notion and P-conscious content is not system-relative

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Sharpening the Concepts of P-Consciousness and A-Consciousness• Four differences:• P-conscious states phenomenal, A-conscious states

representational• A-conscious states always transitive (states of consciousness of

or about), P-conscious states sometimes transitive, sometimes intransitive

• A-consciousness is a functional notion, A-conscious content is system-relative; P-consciousness is not a functional notion and P-conscious content is not system-relative

• There are P-conscious types of state since every P-conscious token must be P-conscious, but there are no A-conscious types since any A-conscious token might fail to be A-conscious

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P-conscious Types of State, but No A-conscious Types

• Block: “For example the feel of pain is a P-conscious type – every pain must have that feel.”

• “But any particular token thought that is A-conscious at a given time could fail to be accessible at some other time, just as my car is accessible now, but will not be later when my wife has it. A state whose content is informationally promiscuous now may not be so later.”

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P-Consciousness Without A-Consciousness, and Vice Versa

• Block proposes sharpening the concepts of P-consciousness and A-consciousness by asking if we can imagine the one without the other.

• Importantly, since Block’s paper concerns the concepts of consciousness, there do not need to be real-world cases for Block to make his point.

• All that is required is that there be cases that are “conceptually possible.”

• As he writes, “Actual cases will be more controversial.”

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A-Consciousness Without P-Consciousness

• Full-fledged “phenomenal zombie” – controversial whether these cases are conceptually possible – it is Block’s view they are

• Blindsight-like cases (a kind of “absent qualia” case)– Ordinary blindsight – no A-conscious content in the blind field,

information “not available as a premise in reasoning”– “Superblindsight” – trains to have the blindsighter’s thoughts,

without external prompting – the perceptual state causing the thought is A-conscious, not P-conscious

– The super-duper-blindsight – where a quasi-zombie has blind and sighted fields that differ only in his regarding them differently

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P-Consciousness Without A-Consciousness

• Brain-damaged animal having P-consciousness but damaged centers of rational control

• Subsystems of the brain might be P-conscious but without sufficient machinery for reasoning and rational control of action

• Pneumatic drill case – P-conscious for a time of the sound but then suddenly both P-conscious and A-conscious of it.

• Freudian case – a P-conscious desire not subject to rational control.

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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”

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Block on “Monitoring Consciousness”

• “The idea of consciousness as some sort of internal monitoring takes many forms…. Given my liberal terminological policy, I have no objection to monitoring-consciousness as a notion of consciousness. Where I balk is at the idea that P-consciousness just is one or another form of monitoring-consciousness. To identify P-consciousness with internal scanning is just to grease the slide to eliminativism about P-consciousness.”

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The “Inner Sense” View: “Higher Order Perception”

• Recall Locke’s statement of the Inner Sense View in the Essay:• “[T]he other fountain from which experience furnisheth the understanding

with ideas is the perception of the operations of our own mind within us, as it is employed about the ideas it has got; which operations, when the soul comes to reflect on and consider, do furnish the understanding with another set of ideas, which could not be had from things without. … This source of ideas every man has wholly in himself; and though it be not sense, as having nothing to do with external objects, yet it is very like it, and might properly enough be called internal sense. But as I call the other sensation, so I call this reflection, the ideas it affords being such only as the mind gets by reflecting on its own operations within itself. By reflection then, in the following part of this discourse, I would be understood to mean, that notice which the mind takes of its own operations, and the manner of them, by reason whereof there come to be ideas of these operations in the understanding.” (Essay, Book II, Ch. 1, sec. 4)

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Armstrong’s Statement of the Inner Sense View

• Armstrong in A Materialist Theory of Mind cites Kant as his source rather than Locke, but he has the same view in mind:– “I believe that Kant suggested the correct way of

thinking about introspection when he spoke of our awareness of our own mental states as the operation of ‘inner sense.’ He took sense-perception as the model of introspection. By sense-perception we become aware of current physical happenings in our environment and our body. By inner sense we become aware of current happenings in our own mind.”

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Armstrong’s Replies to Three Objections

• To critics who say that introspection requires only the need to make true statements about one’s mental states, he claims animals introspect without making statements. He could have added infants.

• To critics who say there’s no analogy to perception since no sense organ is involved, he says there is one to bodily perception, which uses no sense organ.

• To those critics who claim that nothing should be called bodily “perception,” Armstrong replies that then there would be no way classify things that are much less sense perception.

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What Must Be Added to the Behaviorist Account of Consciousness?• Armstrong, as a good functionalist, begins with the behaviorist

account of consciousness and asks what must be added to it.• “Consciousness is something more than an inner state apt for

the production of certain sorts of behavior,” he writes. “But what more?”

• He answers by considering three cases:– One’s driving a long distance and “coming to” at a certain

point, realizing that one had driven many miles without consciousness of the driving.

– Thinking about a problem and being “lost to the world.”– Self-consciously scrutinizing the contents of one’s mind.

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Armstrong’s Analysis

• Armstrong says that in the first case one was perceiving and acting purposively but without being conscious of perceiving and acting purposively.

• In the other two cases, one is conscious of one’s thoughts and experience, although he says that in the second case one is not conscious of one’s thoughts as one’s thoughts.

• Thus, he concludes that what must be added to the behaviorist’s account is awareness – – “I suggest that consciousness is no more than awareness

(perception) of inner mental states by the person whose states they are.”

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Objections to the Inner Sense View

• The view does not seem to be explanatory, if we want it to explain the qualia of our conscious states, since we would need now to explain the qualia of our inner perceptions. We simply postpone explanation.

• And “inner sense” would be radically unlike ordinary perception since in ordinary perception there is an obvious difference between the properties of the perception and the properties of the thing perceived. Here there is no obvious difference. Thus any higher-order qualities are mysterious.

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Rosenthal’s Response

• Rosenthal draws a specific moral from these criticisms:

• “[I]f the higher-order qualities are neither the same as nor distinct from our first-order qualities, the higher-order states in virtue of which we are conscious of our conscious states cannot have qualities [qualia, I take him to mean] at all. But if those higher-order states have no qualitative properties, they can only be higher-order intentional states of some sort.”

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The HOT Theory of Consciousness

• This leads Rosenthal to propose the Higher-Order Thought (HOT) Theory of Consciousness

• It can be roughly stated in this way:• X is a conscious state →

(1) X is accompanied by a thought T, and(2) T has the content that one is in X.

• Rosenthal writes: “[W]e are conscious of our conscious states by having thoughts about them.”

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Characteristics of Rosenthal’s Higher-Order Thoughts

• Occurrent, not dispositional– Merely being disposed to have a thought about a thing

does not make one conscious of that thing

• Assertoric– If we think such-and-such is so-and-so, we assert it to

ourselves, not merely entertain its truth

• Noninferential– Our thought does not result from any inference about

the state it is about – the connection is too immediate

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We Are Not Conscious of HOTs

• Rosenthal recognizes that we are not conscious of having any such higher-order thoughts, much less all the higher-order thoughts that it might seem that we would be required to have.

• But this is no problem, he says – “we are conscious of our HOTs only when those [higher-order] thoughts are themselves conscious, and it’s rare that they are.”

• This is because the HOTs are conscious only when there are still higher-order thoughts about them.

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Rosenthal’s Analysis of Sensory States

• Rosenthal analyzes sensory consciousness in terms of (1) a mental state’s having a sensory quality, and (2) the mental state’s having state consciousness.

• He thinks that these can come apart. He cites:– Subliminal perception– Peripheral vision– Blindsight

• His conclusion is that consciousness is not intrinsic to sensory quality.

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The HOT Analysis

• Thus, Rosenthal suggests that our consciousness (our “state consciousness”) of sensory qualities is just our having of higher-order thoughts about mental states with those sensory qualities.

• Thus, his analysis of qualia • He thinks that wine tasting illustrates this• We learn new concepts for our gustatory and

olfactory experiences, by making us conscious of sensory qualities we were not previously conscious of.

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Difference Between Block and Rosenthal

• The cases that Rosenthal analyzes as cases in which consciousness is lacking from sensory states Block would analyze as cases of P-consciousness without A-consciousness – think of the drill case.

• Block wouldn’t grant Rosenthal’s premise, that the sensory qualities in the cases lack consciousness.

• Their lacking A-consciousness, Block would argue, does not mean they lack P-consciousness.– Given the Ambiguity Hypothesis, Block could even say that Rosenthal

equivocates in his use of the term “consciousness.”– Block separates P-consciousness & “monitoring consciousness”

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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)

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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?”

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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.”

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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.”

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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.”

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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)

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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 concerning Heil• Block attacks it by distinguishing A- from P-consciousness

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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.”

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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

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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

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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.’”

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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.”

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Peacocke’s Trees Example

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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.

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Binocular Vision Example

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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.

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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.

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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.

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Necker Reversible-Cube Illusion Example

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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.

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Comparison of Wittgenstein’s Duck-Rabbit and the Necker Cube

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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.)

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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.”

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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.