csness.ppt

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csness.ppt

• version 20091211

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Notes towards aComputational Theoryof
Consciousness

• William J. Rapaport
• Department of Computer Science Engineering,
• Department of Philosophy, Department of
  Linguistics,
• and Center for Cognitive Science
• rapaport_at_cse.buffalo.edu
• http//www.cse.buffalo.edu/rapaport

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2 (or 3) Questions for a Computational Theory of
Consciousness

• Could a computational cognitive agentbe
  conscious?
• I think so
• But it depends on whats meant by conscious
• 1.5. If so, how would we build one?
• Answer depends on psychological theories of
  consciousness
• How would we know?
• We wouldnt
• any more (or less) than we know about humans!

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And What about Qualia?

• What are qualia? What are numbers? ?
  What is the base case of a recursion?
• Problem of role of qualia in theories of
  consciousness Problem of mathematical
  structuralism

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What Is Consciousness?

• What is consciousness? From the OED
• L. con- together sci- knowingknowing
  something with others,knowing in oneself, privy
  to
• 1601 (Ben Jonson) Attributed to inanimate
  things as privy to, sharing in, or witnesses
  of human actions or secrets
• 1620 having the witness of ones own judgment or
  feelings, knowing within oneself
• 1651 (Hobbes) knowing, or sharing the knowledge
  of anything, together with another
• Not overly helpful

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• Perhaps slightly more helpful?

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Kinds of Consciousness

• Chalmers
• Psychological consciousness
• Phenomenological consciousness
• Better
• Psychological problems of consciousness
• Phenomenological problems of consciousness

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Psychological Consciousness

• Chalmers
• awakeness, introspection, reportability,
  self-consciousness, attention, voluntary
  control, knowledge, awareness
• The easy problems
• I.e., those explainable in principle
  infunctional / computational or neural terms,
  viz.

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Psychological Consciousness

• the ability to discriminate, categorize, and
  react to environmental stimuli
• the integration of information by a cognitive
  system
• the reportability of mental states
• the ability of a system to access its own
  internal states
• the focus of attention
• the deliberate control of behavior
• the difference between wakefulness and sleep.
  etc. (Chalmers 1995, Facing Up to the
  Problem of Consciousness)

• I.e., awareness
• Blocks access consciousness

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Psychological Consciousness

• Models
• Cartesian theater
• a big no-no for humans
• global workspace
• Baars, Franklin, Dehaene, et al.
• Andersons ACT-R buffers
• multiple drafts, fame in the brain
• Dennett

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On Multiple Drafts

• On the critical question of which version of the
  novel Frankenstein is truest or best, however,
  Charles E. Robinson editor of a scholarly
  edition of the Frankenstein Notebooks demurs
  These texts of Frankenstein are what we call
  fluid texts, he says. There is no single
  edition we can judge to be the best.
• Howard, Jennifer (2008), The Birth of
  Frankenstein, Chronicle of Higher Education
  55(11) (7 November) B12-B15 quote on p. B15.
• For fluid texts, read multiple drafts.

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Psychological Consciousness

• 1.5. Reflexive consciousness (Block)
• special case of access consciousness
• HOT (Rosenthal)
• self-representational experiences (Kriegel)
• Any of these models
• global workspace
• HOT
• multiple drafts,
• could be implemented
• neurally
• computationally

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Phenomenological Consciousness

• experience,what its like,qualia
• ??
• yes (Searle, Chalmers, Nagel, McGinn, Block,
  G.Strawson)
• no (Dennett)

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Phenomenological Consciousness

• I can explain to you what love is until I turn
  blue in the face. I can take two weeks to
  explain everything to you. But there is no
  way I can make you feel it until you feel it.
  (p. 40)
• Schmidle, Nicholas (2008), Faith Ecstasy,
  Smithsonian 39(9) (December) 36-47.
• Cf. Jacksons Mary the color-blind color
  scientist
• Dennett
• Qualia cant be described (in language)
• ? Dont have to/cant explain them

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Phenomenological Consciousness

• Dennett (contd)
• ?? qualia
• ? only reports of them
• Dont have to explain why you experience green or
  pain
• Because you dont!
• Only have to explain why you say that you do!
• cf. How would your experience be different
  if Earth revolved around Sun? (Wittgenstein)
• What we think are qualia are really just states
  of psychological consciousness

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Phenomenological Consciousness

• Could phenomenological consciousness (qualia)
  be nothing but neuron firings?
• yes
• Searle Its just biology (like digestion)
• WJR
• Its biology for humans
• but it could be implemented otherwise for
  computers
• (more later)
• no
• Chalmers ? non-physical, phenomenological
  properties
• McGinn Its an unsolvable mystery (for us)
• Nagel It can only be experienced
• yes?
• G.Strawson
• Because everything is experiential, including
  neuron firings.

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NagelWhat Is It Like to Be a Bat?
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What Is It Like to Be a Bat?

• Cf. The Boy Who Sees through Sound
• Discovery Health documentary
• People (14 July 2006)
• http//www.people.com/people/article/0,26334,12125
  68,00.html

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Phenomenological Consciousness

• Could phenomenological consciousness (qualia)
  be nothing but neuron firings? (contd)
• no (contd)
• Chalmers
• phenomenological consciousness is independent of
  physics biology
• mental properties cant be logically derived
  from physical properties
• because of the Argument from Zombies
• but ? 1-1 correspondence
• i.e., ? psycho-physical laws

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Is Consciousness Univocal?

• Maybe there are lots of different kinds of,or
  aspects to, consciousness
• Maybe more than one theory is correct
• Block, in Cognition 79 (2001) 217

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Some Philosophical Positions

• Consciousness does not exist
• Dennett
• There are physiological processes nothing else
• ________ ?

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Some Philosophical Positions

• Consciousness exists
• Nagel Consciousness exists can
  only be experienced
• _________ ?
• McGinn Consciousness exists
  cannot be understood
• ?????????? ?
• (a) (b) seem very close

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Some Philosophical Positions

• Searle Consciousness exists its
  biologically caused
• ?
• Chalmers Consciousness exists
  its independent of physics/biology,
  but theres a 1-1 correspondence
  (there are psychophysical laws)
• ??_________ ?

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The Hard Problem (Chalmers)

• Recall the distinction between
• Psychological concept of mind/consciousness
• as causal/explanatory basis of behavior
• functional characterization
• what mind does
• Phenomenal concept of mind/consciousness
• experience, qualia, what its like
• how mind feels

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The Hard Problem

• The hard problem
• the problem of experience
• How are organisms subjects of experience?
• Why do we experience sensations as we do?
• Why how does physical processing give rise to
  our rich inner life?(all quotes/paraphrases
  from Chalmers 1995)

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A Brief Look Ahead

• Suggestion
• Easy problem
• i.e., the functional characterization of
  psychological consciousness
• is like a recurrence relation or recursive
  clause of a recursive definition or
  mathematical structuralism
• Hard problem
• i.e., qualia, or phenomenal consciousness
• is like the initial conditions or base
  case or objects that play roles in
  mathematical theories

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Chalmerss Zombie Argument(simplified version)

• A zombie is_def a creature that isphysically
  behaviorally indistinguishable from us,but that
  has no conscious experiences.
• http//consc.net/zombies.html
• http//plato.stanford.edu/entries/zombies/
• Physicalism is_def the theory that mental states
  processes (logically) supervene on physical SP
• I.e., any physical duplicate of me would
  also be a psychological duplicate
• Physicalism ? zombies are not conceivable
• But zombies are conceivable
• ? Physicalism is false
• ? Psychological phenomena (e.g., qualia) are
  something over and above physical phenomena

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Ways to React to the Zombie Argument

• Thats right! (Chalmers)
• So wed better devise a separate theory of
  psychological consciousness
• take mental terms as primitive, not
  characterizable in physical terms
• cf. Newton gravity
• some psychophysical laws to tie them in
  with the physical world
• mostly 1-1 correspondences

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Ways to React to the Zombie Argument

• There cant be any zombies
• Any sufficiently complex cognitive system
  (including any duplicates of me) will have just
  as much subjective mentality as I do
• Dennett I.e., none
• Or Commander Data will really be just as
  phenomenally conscious as I am (and I really am
  so!) ()

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Ways to React to the Zombie Argument

• () How to give a zombie consciousness?
• A calculator has the ability to add
• but it does so unconsciously, zombie-like
• Give Cassie a theory of math cognition
• then shed be aware of adding
• shed be conscious of it in both the
  psychological sense and in the phenomenal sense
• shed have the experience of adding
• but what gives her that experience?
• perhaps Rosenthal-like HOT?

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Ways to React to the Zombie Argument

• There can be zombies
• There are plenty of unconscious cognitive
  processes
• People who solved puzzles with insight activated
  a specific subset of cortical areas. Although
  the answer seemed to appear out of nowhere, the
  mind was carefully preparing itself for the
  breakthrough. The scientists refer to this as
  the "preparatory phrase," since the brain is
  devoting its considerable computational power to
  the problem. The various sensory areas, like the
  visual cortex, go silent as the brain suppresses
  possible distractions. "The cortex does this for
  the same reason we close our eyes when we're
  trying to think," Jung-Beeman said. "Focus is
  all about blocking stuff out " (New Yorker, 28
  July 2008, p. 43)
• All of this is unconscious so, zombies are
  possible
• but they could become conscious if another part
  of the brain were aware of it, or watching it,
  HOT-like
• I.e., absent qualia
• So why couldnt all of them be unconscious?

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There Can Be Zombies

• This is the Really Hard Problem
• But then why do we experience some of them?
• Other really hard problems in the vicinity
• Why do we experience things as we do and not
  another way?
• cf. inverted qualia
• Why do we experience red as we do (however we do)
  and not as the sound of a bell?
• cf. synaesthesia

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Qualia

• A quale (plural qualia) is
• a raw feel,
• a phenomenal experience,
• what its like
• Its what you experience when you
• sense a color,
• or hear a sound,
• or taste, or smell, or touch.
• Its what Chalmers says needs to be explained

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Qualia The Classic Problem

• Psychological consciousness can be characterized
  functionally (i.e., computationally)
• I.e., in terms of causal and logical relations
• between inputs and internal concepts,
• among internal concepts,
• between internal concepts and outputs
• Qualia cannot be characterized functionally
• Because of the possibilities of
• absent qualia
• inverted qualia
• ? Qualia are not psychological
• or else Psychological consciousness cant be
  characterized functionally

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Do Qualia Exist?Wittgensteins Beetle in the Box

• "Suppose everyone had a box with something in it
  we call it a beetle. No one can look into
  anyone else's box, and everyone says he knows
  what a beetle is only by looking at his beetle.
  Here it would be quite possible for everyone to
  have something different in his box. One might
  even imagine such a thing constantly changing.
  But suppose the word beetle had a use in these
  people's language? If so it would not be used
  as the name of a thing. The thing in the box has
  no place in the language game at all not even as
  a something for the box might even be empty. No,
  one can divide through by the thing in the box
  it cancels out, whatever it is."
• (Ludwig Wittgenstein, Philosophical
  Investigations I, 293)

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Qualia

• Are qualia beetles in boxes?
• Dennett yes!
• Chalmers
• maybe (?)
• but I do have a beetle in my box
• even if zombies dont have beetles in theirs!

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Are Qualia Beetles in Boxes?

• WJR
• we do have qualia
• even if we may be misled by them or misremember
  them
• we are phenomenally conscious
• even if sometimes we may not remember it
• e.g., blanking out when driving or daydreaming

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The Hard Problemfor me!

• No matter how detailed our theories of
  psychological consciousness are,I do experience
  qualia
• Castañeda
• Philosophy must be done in the first person, for
  the first person
• What is that which I experience?What is
  experience itself?
• If I try to characterize it in terms of other
  aspects of my mental economy,it loses its raw
  feel nature
• But if it is primitive, how can I understand
  it?
• Want a theory of qualia that is consistent with
  computational theory of consciousness

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2 Main Questions about Qualia

• Why ( how) do we experience anything rather than
  nothing?
• the zombie question
• the really hard problem
• Why are our qualia as they are not like
  something else?
• answer may depend on answer to 1

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Why Do We Experience Anything Rather than Nothing?

• Some plants are sensitive to light,some to what
  we would call odors
• I.e., airborne chemicals
• Can they see or smell?
• Do we see or smell?
• Or are we, too, merely light-
  chemical-sensitive?
• Does anything further happen in the brain?
• I.e., qualia?
• Or are qualia just our sensitivity to the light
  chemicals?
• Or is there any sensitivity (or sensation) at all?

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Why Do We Experience Anything Rather than Nothing?

• Cf. visual quale of seeing a red (traffic) light
  with olfactory quale of an odor
• Cf. these with the lack of an olfactory quale
• We are qualitatively insensitive to many odors
• We are certainly less sensitive than a dog
• Yet ?ly these odors do influence our behavior
• blind smell cf. blindsight
• If so, then we are at least partial zombies
• How could that be?
• Why is there such a difference?
• Does the (visual or olfactory) quale do anything?

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Why Do We Experience Anything Rather than Nothing?

• Cf. my visual quale of a red light with my
  absence of a visual quale for infrared
  light
• Suppose infrared light influenced my behavior but
  I was not subjectively aware of the IR light
• I could be objectively aware of it
• via an objective sensing device
• via monitoring my brain
• Would that feel like anything?
• Maybe like an intuition
• Thats a quale, but not necessarily a quale of
  the IR light
• 2nd-order quale? HOT?
• But probably not like a visual experience of red
  light
• It wouldnt be a deeper red

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Why Do We Experience Anything Rather than Nothing?

• Whats the difference in my behavior between
• my reaction to the quale of red light
• my reaction to IR light w/o quale?
• Case 1
• I can voluntarily react (or not react) to the
  quale of red light
• doesnt run afoul of problem of free will
• whatever free will turns out to be will work here
• Case 2
• I have no choice
• especially if there is not even an intuition

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Why Do We Experience Anything Rather than Nothing?

• So we can be partial zombies
• but not complete zombies
• because
• a complete zombie would have no free will
• but we do
• If the complete zombie had free will,it would
  then also have to have some HOT/access/awareness
  of the impingement of the external object(s)
• chemicals for odor, photons for vision, etc.
• on its sensory apparatus

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Why Do We Experience Anything Rather than Nothing?

• Knowing that the external object has so impinged
• being aware of its impingement
• from the 1st-person POV
• i.e., subjective awareness
• not objective awareness
• is the experience of a quale
• but ?ly ? inverted qualia
• i.e., what the quale feels like may ? physical
  implementation

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Why Are Some Stimuli Experienced as Colors
Others as Sounds?

• ?ly because of different sources?
• photons
• sound waves
• chemicals in air
• But could be all felt on a common spectrumrather
  than by orthogonal experiences
• ?ly they are synaesthesia?
• Why are some things experienced at all, some
  things differently, but others not at all?
• ?ly because of evolutionary usefulness
• voluntary ability to perform the 4 Fs
• odors are not useful to us, but are to dogs

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Qualia

• Chalmers
• A mental state or process (MSP)can be
  characterized functionally
• external to the mental state or process
• behavioral
• in terms of the MSPs I/O relations to other MSPs
• its role in the cognitive economy
• A conscious MSP can also be characterized by
  what its likeits quale
• internal
• phenomenal
• by definition without functional role
• like Wittgensteins beetle in the box

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Qualia

• Cf. the monetary economy
• A dollar has the value it has because of the
  role it plays in the world monetary economy
• Does it have an intrinsic value? (a quale?)
• Dennett
• Does a dollar have something logically
  independent of its functionalistic exchange
  powers?
• no there is no economic theory of such
  intrinsic value
• WJR
• at best, s intrinsic value isits role in the
  world economy.
• might play several roles at once
• cf. Hofstadter on value of Polish zloty
• Maybe the value of the paper its printed on?
• But that value is a function of the world
  monetary economy!

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Qualia

• Cf. axiom systems intended interpretations
• Can characterize the natural numbers only as
• any sequence that satisfies Peanos axioms
• But an ? of sequences do that
• Theres no way to pick out the natural numbers
• trying to do that is like trying to characterize
  qualia
• Arithmetic is, in this sense, all there is to
  number there is no saying absolutely what the
  numbers are there is only arithmetic
• Quine 1969 45
• I.e., numbers qualia arithmetic cog.
  economy
• Maybe a cog. agents internal mental
  representation of numbers corresponds to the
  qualia?

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Qualia

• Benacerraf 1965 What Numbers Could Not Be
• 3 is neither Ø, Ø, Ø,Ø nor Ø (
  it cant be both)
• each has properties relations that the other
  lacksand that are irrelevant to numbers, e.g.
• on both theories, numbers have set-theoretic
  cardinality
• on one theory, 3 3 on the other, 3 1
• on one theory, 1 ? 3 on the other, 1 ? 3
• none of these are true of the natural number 3
• Any object can play the role of 3
• Arithmetic isthe science that elaborates the
  abstract structure that all progressions have in
  common.It is notconcerned with particular
  objectsthe numbers. The search for which
  independently identifiable particular objects the
  numbers really areismisguided.

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Qualia

• Burgess 2001, Set Theory
• The ordered pair (a,b) is defined to be
  a,a,b, and from this definition the basic
  law of ordered pairs, that (a,b)(c,d) iff ac
  and bd, is deduced. It is not pretended that
  this definition reveals what ordered pairs
  really were all along. What the definition and
  derivation of the basic law do show is that the
  positing of ordered pairs subject to this basic
  law as entities over and above sets is, in a
  sense, superfluous.

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Qualia

• What is a graph?
• def a structure consisting of
• a set V of vertices
• a set E of edges,
• with certain relationships among the members of V
  E
• But what is a vertex? what is an edge?
• anything that satisfies the relationships among
  the members of V E
• So, a telephone network really is a
  graph,because we can take phones to be
  vertices phone connections to be edges
• Its not merely that a phone network can be
  modeled as (or by) a graph
• It really is one!

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Qualia

• Logically speaking, vertices edges are (types
  of) variables that can take as values certain
  phones connections
• such talk of variables is just talk of roles that
  can be played by certain (usually physical)
  objects
• the objects implement those roles (i.e., those
  abstractions)

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Qualia

• Veblen (on his axiomatization of geometry)
• The terms point and orderdiffer from the
  other terms of geometry in that they are
  undefined. (p. 344)
• Because they are undefined, we are not told what
  they are
• Therefore, they can be (implemented by) anything
  that can play their roles
• Cf. Hilbert on geometry
• "One must be able to say at all timesinstead of
  points, lines, and planestables, chairs, and
  beer mugs.

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Qualia

• But Veblen
• there is essentially only one class of which
  theaxioms are valid (346)
• I.e., one class up to isomorphism
• In more exact language, any two classes K and K?
  of objects that satisfy theaxioms are capable of
  a one-to-one correspondence between them
• i.e., they are isomorphic

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Qualia

• Hilbert would agree
• But, in terms of qualia
• a set of points and lines (as Euclid thought of
  them) that satisfy the axioms
• a set of tables and chairs that satisfy
  the axioms
• are like a spectrum and an inverted spectrum

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Qualia

• White 1974, What Numbers Are
• allegedly rebuts Benacerraf
• but really consistent with it
• focuses on the role-filler rather than the role
• a certain set is a 3 in a certain series
• I.e., it plays the role of a three
• just as Richard Burton played the role of Hamlet
  in the celebrated 1964 production
• There are indeed numbers, and there are plenty
  of them
• Yes and there are plenty of different qualia,
  too
• cf. inverted spectrum

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Qualia

• Cf. Rapaport 1999 on implementation as semantic
  interpretation
• The number 3 is anything that implements the 3rd
  item in a sequence that satisfies the abstraction
  described by Peanos axioms.
• So, is a quale of a MSP anything that implements
  it?
• where it is characterized functionally,i.e.,
  in terms of the cognitive economy?

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Qualia

• Gert, What Colors Could Not Be, JPhil 2008
• 2 ways to answer What is X?
• Better 2 ways to interpret X is Y
• like 3 Ø, Ø, Ø,Ø
• like water H2O
• (1) is part of the answer given in terms of a
  relational theory describing what any candidate
  for X must satisfy, by giving the script for
  any actor playing the role of X
• (2) gives a particular thing that plays the role

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Qualia

• But if there is a functional characterization of
  water
• e.g., Chalmerss watery stuff
• or my view of the narrow meaning of water
• then H2O is just one actor that can play the
  role
• and Twin Earths XYZ is another
• Its not that Hamlet is Richard Burton
• rather, Burton is one among many who have played
  the role
• in a particular production, Hamlet Burton

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Qualia

• Alternatively, compare
• ? is (or is a or plays the role of) 3
• Burton is (or plays the role of) Hamlet
• 3 S(2)
• which is a functional/structural definition

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Mathematical Structuralism Qualia

• The structural view of math doesnt require /
  allow us to specify what 3 is
• Only defines it in terms of its role
• Still
• When I do arithmetic, I implement 3 somehow
• e.g., as ?
• or as 3 (most likely!)
• or as my internal mental numeron

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Mathematical Structuralism Qualia

• The functional view of cognition doesnt require
  / allow us to specify what qualia are
• Only defines them in terms of their role
• Still
• They have to / can be implemented
• and thus I do experience red in a certain way

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Qualia

• Block in Cognition 79(2001)203f
• Functionalism identifies consciousness with a
  role
• just like numbers
• Physicalism identifies consciousness with a
  physical or biological property that fills or
  implements or realizes that role in humans
• just like water H2O
• The big question How do you know that it is
  broadcasting in the global workspace that makes a
  representation conscious as opposed to something
  about the human biological realization of that
  broadcasting that makes it conscious?
• My answer
• You dont!
• Hence the possibility of absent qualia (i.e.,
  zombies).

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Qualia

• Dehaene on physicalism (Cognition 79(2001)30)
• qualia might be biological properties of
  consciousnesss workspace
• each workspace state is highly differentiated
  and of high complexity.thus the flux of
  neuronal workspace states associated with a
  perceptual experience is vastly beyond accurate
  verbal description or LTM storage.Although the
  major organization of this repertoire is shared
  by all members of the species, its details result
  from a developmental process of epigenesis are
  ? specific to each individual. Thus, the
  contents of perceptual awareness are complex,
  dynamic, multi-faceted neural states that cannot
  be memorized or transmitted to others in their
  entirety.
• This could account for inverted, if not absent,
  qualia

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Qualia

• But why am I perfectly content with the inability
  to uniquely characterize the natural numbers
• yet discontented with the inability to uniquely
  characterize qualia?
• how are natural numbers and qualia asymmetric?
• ?ly The quale of a MSP is not characterizable
  in terms of its functional relationships
• but in terms of how the experiencer relates to
  it
• but that runs into the value-of-a- problem
• its ultimately defined in terms of other MSPs
• leads us back to Dennett

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Qualia

• ?ly Nature of a quale must lead out of the
  network of MSPs, into
• the physical implementation?
• then we would have to allow for
• inverted absent qualia, depending on the
  implementation
• a bullet we might have to bite!
• gets us out of the mental-functional circle
• remains physical
• see Rapaport 2005, "Implementation Is Semantic
  Interpretation Further Thoughts!

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Qualia

• If MSPs are physically implemented,then qualia
  are part of the big picture, after all
• they are values of variables
• those variables are part of the mental
  (functional, computational) theory
• their values are part of the physical
  implementation of that theory
• a side effect
• an implementation detail
• qualia-variables w/o values are absent qualia
• such MSPs would be unconscious
• qualia-variables with different values are
  inverted qualia

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Qualia

• What else might qualia be like?
• Given an equivalence or an analogy
• where you dont know the value of either,you
  cant fully understand it.
• The other magicians nod, knowingly, like
  bird-watchers seeing an unusual find in the
  middle distance
• (Gopnik, The Real Work, New Yorker (17MR0857)
• ?ly the relation between an MSP and its quale is
  like an analogy
• by experiencing, hence understanding, the quale,
  we thereby come to understand (and undergo) the
  MSP
• Is a quale like a truth value?
• and the causal-functional role of a MSP is its
  proof theory?

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Qualia

• Consider a recurrence relation, or recursively
  defined function
• f(0)q f(n1)g(f(n))
• the recursion is like the functional theory of
  consciousness
• Morbini Schubert Its like access
  consciousness
• the base case is like the quale
• Morbini Schubert (sort of) Its like
  phenomenal consciousness
• if h(0) r ? q h(n1)g(h(n)), then we have 2
  distinct functions with the same functional
  theory but different qualia
• the recursion without the base case is like
  absent qualia.
• The base case is a particular implementation of
  the recurrence.
• OR ?ly g is whats like the quale?
• models/implementations of Peanos axioms can
  differ in what they take 0 to be (base case) as
  well as in what they take S to be (i.e., what g
  is).

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Qualia

• The principal contrast is between
• pattern (or function)
• thing (or matter, or shape)
• Hofstadter, Ton Beau de Marot 307f
• Consider a semantic network representing a
  functional characterization of the mind
• Dennett thats all thats needed
• Chalmers the nodes need identifiers
• identification independent of their connections
• if they do (if they are filled in),then what
  they are filled in with are qualia and if
  yours are filled with something different from
  mine, then we have inverted
  qualiaelse we have absent qualia
• qualia are dependent on the implementing medium M
• can be absent or can vary with varying M

74
Qualia

• Could qualia be nothing but neuron firings?
• ?ly
• our phenomenological / qualitative experience
  is just our first-person acquaintance with the
  neuron firings
• i.e., it is just the way those neuron firings
  feel
• this might depend on the implementation

75
Does It Matter(for a Computational Theory)?

• When I look at a red box, it seems and looks red
• If you look at it, could you really see it
  differently?
• We both can describe it in the same way react
  to it in the same way.
• We both can look at a painting discuss its
  colors, shapes, and emotional significance,
  agree (or agree to disagree) about its beauty
• How could that be if we are having very different
  experiences?

76
Does It Matter?

• Simplest explanation
• We are having the same or very similar
  experiences!
• Cf. simplest explanation of why we see the
  world as we do
• The world is as we see it
• modulo limitations of our sensory apparatus
• a bat or color-blind dog would see things very
  differently
• but I wouldnt expect to be able to sympathize
  with its aesthetic judgments as I do with yours
• cf. Winstons problem (Rapaport 2003, on
  negotiation) Wittgenstein If a lion
  could talk, we wouldnt understand it
• cf. Dennett if a lion could talk, not only
  would we understand it, but
  other lions wouldnt!

77
Does It Matter?

• Computers can be conscious
• either for Chalmerss reasons
• or for Dennetts
• But computers might not have to be consciousin
  the way that humans are.
• Whether they are cannot be known (by us)
• from 3rd-person POV, we cant know anothers
  qualia
• we can only know our own, from the 1st-person POV
• but theres no good reason to think others are
  zombies
• If it cannot be known, thentheres no moral
  reason to treat even possible zombies (who are
  behaviorally indistinguishable from us) any
  differently from us