The MindBody problem

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The Mind/Body problem

• From Descartes to a Smart Place
• Putnam

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I. Simple framing
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2 Senses of the problem (Chalmers 1996)

• 1) Psychological
• Mental states cause behaviour
• This is (largely) a mechanical/behavioural
  problem
• Problem of mental causation
• 2) Phenomenal
• Mental states feel certain ways
• How do we get these feelings out of body/brain?
• This is a metaphysical problem
• Problem of consciousness

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II. A more precise framing of the problem

• Inconsistent Tetrad (Ludwig 2003)
• 1) Realism
• Some things have mental properties.
• 2) Conceptual autonomy
• Mental properties are not reducible to
  non-mental (material) properties.
• 3) Constituent explanatory sufficiency
• A constituent description of a thing entails a
  complete description of it.
• 4) Constituent non-mentalism
• Basic constituents of things do not have mental
  properties as such.
• Each proposition is independently plausible.
• The truth of the conjunction of any 3 of these
  propositions entails the falsity of the fourth.
• .Inconsistent tetrad

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• Independent plausibility of (1)-(4)
• (1) Realism
• Just seems obviously true
• Introspect
• Folk mindreading
• (2) Conceptual autonomy
• If mental conceptually reduced to the
  non-mental, then non-mental propositions must
  entail mental propositions.
• But
• (a) We can imagine non-material, mental
  things
• -Gods, angels, spirits are at least
  conceivable
• -Thus material is not conceptually necessary
  for mental
• (b) We can imagine material, non-mental
  things
• -Our mental states cause behaviour
• -We can imagine our behaviour resulting from
  other causes e.g. from our physical body
  without conscious states
• -Thus material is not conceptually sufficient
  for mental
• Thus as a conceptual point, non-mental
  propositions do not entail mental ones.
• Thus mental concepts cannot be reduced to
  non-mental (material) concepts.

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• (3) Constituent explanatory sufficiency
• Look to the success of science
• Successful explanation of behaviour of
  complex systems is done in terms of
  constituents and the laws that govern them.
• This is how our best science works it is
  usually enough!
• (4) Constituent non-mentalism
• Again look at successful science
• Physics explains the world without any appeal
  to mental properties
• Mass, spin, velocity, size
• So it looks like basic constituents of the
  world do not have mental properties.
• So (1)-(4) are independently plausible, but
  conjointly inconsistent.
• Solving the mind/body problem requires rejecting
  one of (1)-(4) to maintain logical consistency.

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• III. Logical space
• Reject (4)- Ontological anti-reductionism
• Substance Dualism (Descartes)
• Substance
• Aristotle- that which is neither said of a
  subject nor in a subject
• Medieval scholastics- independent existents
• Substance as property bearer
• 2 kinds of substance
• Material (Corporeal)
• Body characterized by extension (categorical
  property)
• Mental (Thinking)
• Non-material
• Mind characterized by thought (categorical
  property)

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• Argument?
• Descartes Modal Argument
• (1) I (Descartes) can conceive of thinking
  (mind) without my
• body (extension).
• (2) It is thus possible that the mind exist
  without the body./
• (C) Mind and body are thus distinct.
• Mind and body have distinct modal properties.
  Thus they are distinct by by Leibnizs law
• Moving from(1)-(2) requires that
  conceivability entails possibility.
• Note that we can also conceive of distinct
  properties in the other direction--of body
  without mind. And so the point generalizes to
  substances, since extension and thought are
  categorical properties for Descartes.

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• Mental causation?
• If we buy the modal argument, how do thoughts
  (mental substance) cause events in the physical
  world (material substance)?
• 2 Options
• (1) Causal interactionism
• (2) Parallelism
• Verdict?
• Even if we are charitable and grant the
  soundness of the modal argument, Descartes has at
  most shown that the mental is possible without
  the material.
• We must then investigate empirically to see if
  it is actual.
• doesnt look so good.

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• Reject (3)- Conceptual anti-reduction
• Deny that a constituent description of a thing
  is or entails a complete
• description of it. So, we could have a
  constituent description of a thing and
• there would be something left over
  (unexplained). Constituent explanations
• are thus not sufficient to explain some kinds
  of things.
• Emergentism (Huxley 1901 Morgan 1923 Broad
  1925)
• -Only material complexes (substance) exist, and
  some of
• these complexes (but not their atomic parts)
  have mental properties.
• -These mental properties are not conceptually
  reducible
• to the physical properties of the complexes that
  have them.
• -Mental properties thus emerge from material
  complexes.
• -If we give a complete description of the
  constituent organization of such complexes, the
  (emergent) mental properties will not be
  deducible from that description.
• Problems Emergentism and mental causation
• Downward causation vs. epiphenomenalism

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• Reject (2)-Conceptual reduction
• Mental properties are reducible to the
  non-mental/material. So once you
• have all the material propositions, the mental
  propositions just follow.
• Reductive Physicalism
• Logical behaviourism (Carnap 1931 Hempel 1935
  Ryle 1949)
• Logical positivism and behavioural psychology
• All mental talk can be translated into
  behavioural talk.
• Verificationism
• How do we test for (verify) mental ascriptions?
• ?behaviour
• Thus the meaning of mental ascriptions are
  behavioural
• B is in pain just means

B is exhibiting (pain) behaviours--wincing,
groaning (or is disposed to given the right
circumstances)
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• Identity theory (Place 1956 Feigl 1958 Smart
  1959 Lewis 1966, 1972)
• Brains???
• Resistance to mind/brain identity
• Leibnizs Mill
• Folk mental terms
• Think of other empirical discoveries
• lightning electrical discharge
• gold element with atomic 79
• morning star the planet Venus
• clouds masses of water droplets
• mental states brain states
• We can maintain the distinct senses of these
  terms consistently with their co-reference.
• To be in pain, is thus just for a certain event
  to occur in the brain.

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• Type vs. token identity theory
• Weak Token identity-All and any particular
  instance of mental kinds can be identified with
  a brain event/process
• Strong Type identity-Mental kinds just are
  physical (brain) kinds
• type identity entails token identity (but not
  vice versa)
• Problems
• Token identity theory lacks generalized
  explanatory power
• Type identity theory is chauvinistic
• Putnam (1967) and multiple realizability
• (1) For any mental state M, there is a unique
  brain state B such that an O can be in state M
  if and only if O is in state B.
• (2) It is conceivable that some Os be in state
  M without being in state B.
• (C) Ms are thus multiply realizable one can
  be in a mental state without being in the
  unique brain state (as posited by Identity
  theory).
• (C2) Type identity theory is false.

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• Functionalism (Putnam 1960 Fodor 1968 Block
  Fodor 1972 Block 1978 Sober 1985)
• Logic, Computation, Multiple realizability, and
  Physicalism
• Mental states can be reduced to functional
  roles.
• Compare
• Identity theory what matters is that the
  brain is in such-and-such state in a way that
  correlates with a mental state.
• Functionalism what matters is what that brain
  state is doing in the overall operation of the
  system.
• We thus identify states (brain, mental) with
  their functional role
• Simplest form
• input ?? ? output
• functional role
• (job description)

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• Reject (1)-Anti-realism
• Eliminativism (Churchland 1981 Stich 1983)
• Deny the reality of mental properties.
• How?
• -Mental terms (the concepts they express the
  properties they pick out) are symptomatic of
  our pre-scientific theories of behaviour
• -With the advent development of neuroscience
  and cognitive psychology, these terms are to
  be replaced with neurophysiological ones.
• -This change is not merely semantic

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• This (briefly) exhausts the
• logical space.
• Our focus
• -functionalism (machine)
• -challenges of physicalism
• -the psychological problem in addition to the
  phenomenal problem