LAST LECTURE

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LAST LECTURE
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Functionalism

• Functionalism in philosophy of mind is the view
  that mental states should be identified with and
  differentiated in terms of functional roles.
• A function (as in mathematics) relates inputs to
  outputs. (e.g. multiplication vs. addition)
• A functional role would determine a specific kind
  of function.

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Functional Concepts (1)

• Part of FUNCTIONALISM is conceptual.
• In a stuff concept, what a thing is and what it
  does is a matter of the nature of the stuff. To
  be water is to be liquid and wet. To be wood is
  to be, to be a sheep is to be .
• Most STUFF concepts are the concepts of certain
  kinds in nature (or natural kinds).

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Functional Concepts (2)

• A functional concept identifies what a thing IS
  with what it does.
• To be a knife, is to be a thing that cuts
• To be money, is to be the kind of thing that
  permits economic exchange
• To be an umpire, is to be the person who
  adjudicates events in a baseball game.
• To be a chess queen, is to be a piece that moves
  and captures in a specified manner.

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Functional Concepts (3)

• If we say that a mental state is a functional
  kind, then we say that to be in pain is to be
  in that state that relates injury to behaviors of
  type T.
• What the mental states have in common is the
  functional profile of relating input to output.
  If two functional states relate the same inputs
  to the same outputs then they are the same
  function.

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Examples

• Two word processing programs will have different
  computer code, but will perform the same work.
  Same function different realization.
• A Calculator and an abacus will both perform
  simple mathematical calculations, but one is
  digital and one is analog.
• A digital clock and a wind-up cuckoo clock both
  keep time, etc.
• Same function different form

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Function and Multiple Realization

• One of the primary reasons people entertain
  functionalism about mental states is that
  functional states are multiply realizable.
• Recall MR was a problem for identity theory.
  Now it is a virtue of Functionalism.

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Functionalism Review

• 1) Functionalism in philosophy of mind is the
  view that mental states should be identified with
  and differentiated in terms of functional roles.
• 2) A function (as in mathematics) relates inputs
  to outputs. (e.g. multiplication vs. addition).
  A functional role would determine a specific kind
  of function.
• 3) Functional Concepts define things relative to
  functions
• 4) Functions are multiply realizable.
• According to Functionalism
• To be in a mental state S is to have your brain
  realize a functional state F.

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Two models
Observable
Not observable

• Behavioral Model

• Mind Plays a role(?) model

Stimuli
WHY ISNT FUNCTIONALISM JUST A VERSION OF
BEHAVIORISM
Stimuli
ConditionedResponses
MENTALEVENTS
Determines Type
Behavior
Behavior
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More Models
Observable
Not observable

• Functional Model

• Mind Plays a role(?) model

Stimuli
Stimuli
Because the functional role determines what the
state is, not the input/output pair
Functional State
MENTALEVENTS
Behavior
that means, e.g., pain and fake-pain are
different states
Behavior
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Hardware Software Analogy

• According to one version of Functionalism
• The brain is like a computer and your mental
  states are like programs that run on that
  computer. The same computer can run different
  programs at different times and the same (or
  similar) programs can be run on different
  computers.

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Objection to Functionalism

• Blocks Liberalism Objection
• If having a functional organization F is
  sufficient for being in mental state M, then
  anything which realizes F will be M.
• So if F1 is being in love with Laura Bush, and
  a crashing wave contains water molecules that
  realize F1, then the wave loves Laura Bush.

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See the unhappy rainbow?
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The Qualia Objection

• Similar to the Conscious experience argument for
  dualism.
• 1) Conscious experience contains more information
  than the physical facts provide What its like
  to X or Qualia
• 2) Qualia has no functional role.
• 3) If functionalism is true there is no
  requirement that functional states have
  associated qualia. Thus mental states need not
  have qualia. (Qualia Zombies)
• 4) But the presence of qualia is paradigmatic of
  consciousness. And consciousness is a mental
  state.-------------------------------------------
  ----------------------
• 5) Therefore, functionalism is not a complete
  account of mental states.

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Functionalism and Artificial Intelligence (AI)

• Non-Biological Realization
• If a functional state can be realized outside of
  a biological system, then can we build a system
  (e.g. in a computer) that has REAL mental states?
• Such a system would be a form of Artificial
  Intelligence. (AI)

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Types of AI

• There are two conceptions of AI
• Strong AI non-biological systems can realize
  real mental states.
• Weak AI non-biological systems can only
  simulate mental states. We can learn about the
  mind by studying these systems, but they are not
  real minds.

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Is Simulation just Simulation?

• Simulated Weather
• Simulated Sunlight
• Simulated Flight
• Simulated Clocks
• What kind of simulation is an AI system?

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Can Machines (really) Think The Turing Test

• In a famous 1950 paper Philosopher-Mathematician
  Alan Turing asked
• Can a machine think?
• To answer the question he proposed an experiement
  called the Imitation Game or (later) Turing Test

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Turing and Turing Machines
ALAN M. TURING He developed a way to resolve
complex mathematical problems using imaginary
machines (digital computers)
One kind of Turing Machine A Turing Bombe
code-breaker
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A Basic Turing Machine Diagram
INPUT
OUTPUT
PROCESSOR
One way to make a TM is to write a program that
wins the Turing Test
MEMORY
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Turing Machines are MR
A Turing machine can be diagrammed or built of
metal or of blueberry muffins and
frosting. AND STILL BE A Turing Machine
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The Imitation Game
A woman in a chat-room answers questions as she
normally would
A Man in a chat-room pretends to be a woman
You may ask any question you want for 15 minutes
via computer. If you cannot tell who the real
woman is, then the man wins. He is
indistinguishable from the woman.
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The Turing Test A computer tries to imitate a
human
COMPUTER
WHICH IS WHICH? IF YOU CANT TELL, IS THERE A
DIFFERENCE?
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Try the Turing Test on your friends

• How do you know that they can think?
• Imagine that you could only talk to them in a
  chat room or in some other setting where behavior
  was not a factor.
• You would ask questions and judge on the basis of
  answers.

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Objections to Turings Claim

• Turing doesnt answer his own question. He gives
  a test, and suggests that computers will be able
  to pass it at some point
• Here are some traditional objections
• 1) The Soul you must have a soul to think.
• 2) Originality Computers must obey programs so
  they cannot do anything original.
• 3) Humor Thinking yields humor, machines dont
  make jokes.
• 4) Head in the Sand Oh dear, wouldnt be awful
  if they did think?
• 5) Learning Machines cant learn, but thinkers
  can.

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Turings Replies

• 1) The Soul you must have a soul to think.
• -- God could make a thinking machine
• 2) Originality Computers must obey programs so
  they cannot do anything original.-- Programs
  could incorporate randomness
• 3) Humor Thinking yields humor, machines dont
  make jokes.-- Why must thinking and humor
  coincide?
• 4) Head in the Sand Oh dear, wouldnt be awful
  if they did think?
• -- A worry is not an objection.
• 5) Learning Machines cant learn, but thinkers
  can.
• -- Complex machines can acquire new inputs from
  the environment and previous processing.

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Searles Chinese Room

• The best known objection to strong AI is John
  Searles CHINESE ROOM objection.

The objection is this If a system can pass the
Turing Test then it understands language, but in
a Chinese Room there is no part that understands
language. So at best a TT simulates thinking.
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The Chinese Room
MEMORY
OUTPUT
INPUT
PROCESSOR