Schneider by liaoxiuli4


									  The Format of Thought: a
Dynamical Systems Approach to
      Intentional Action

                         Susan Schneider
  Department of Philosophy, Center for Cognitive Neuroscience, and
                  Institute for Cognitive Science
                     University of Pennsylvania

• DST purports to be a theory of the nature of thought.
• View of DST in mainstream philosophy of mind: Unclear on
  how low-level explanations in DST can inform traditional
  philosophical problems such as the mind-body problem,
  mental causation, the nature of mental states/events, and
  the free will-determinism debate.

• Today: quick discussion of novel DST view of mental
  causation. Use this view of mental causation to develop a
  position on the free will debate for DST
Approaches to the Nature of

• Naturalism: explain how mental phenomena fit into the world that
   scientific investigates.

• Naturalistic approaches to conceptual thought:
• Connectionism: conceptual thought is a species of pattern recognition in
   which activation patterns spread though a connectionist network (Paul
   and Patricia Churchland, Paul Smolensky).

• Symbol processing approach. Conceptual thought is the manipulation of
   symbols according to algorithms (Fodor, Pinker).

• DST – cognitive systems are kinds of dynamic systems, and as such, they
   are best understood from the perspective of DST.
DST Approach to Mental Causation
• Normal model of causation is “linear causation” (“efficient
  causation”, “billiard ball causation”) in which event E1
  brings about E2. DST: different approach.

• Freeman: “Linear causality fails most dramatically in studies
  of the relations between microscopic neurons and the
  mesoscopic populations in which they are embedded...Such
  interactions are not particular to neurons in neuropil, being
  common in familiar systems such as hurricanes, lasers,
  fires, herds…In each of these cases, particles making up the
  ensemble simultaneuously create a mesoscopic state and
  are constrained by the very state they have created.” (p.
DST and Mental Causation, cont.,
• Scott Kelso, “In synergetics, the order parameter is created
  by the cooperation of the individual parts of the system,
  here the fluid molecules. Conversely, it governs or
  constrains the behavior of the individual parts. This is a
  strange kind of circular causality (which is the chicken and
  which is the egg?), but we will see that it is typical of all
  self-organizing systems. What we have here is one of the
  main conceptual differences between the circularly causal
  underpinnings of pattern formation in nonequilibrium
  systems and the linear causality that underlies most of
  modern physiology and psychology…” (Kelso, 9)

• “Circular Causation”: higher-level emergent patterns
  generate downward causal influence on the physical level.

• Philosophers: Is circular causation coherent?
Kim’s Exclusion Problem
• Not presented against DST specifically, but I’ll apply to
  case of circular causation.

• Idea behind problem: Whenever a mental event is
  proposed as a cause of another event, whether physical or
  mental, its status as cause is in danger of being preempted
  by a physical event—that is, a mental cause is liable to be
  excluded by a physical cause.

• Causal Closure of Physical (i.e., microphysical) Domain.
  General idea, quoting Kim:, “the physical domain is
  causally and explanatorily self-sufficient—that is, to
  explain a physical event, or to identify its cause, there is
  no need to look outside the physical domain.”

• Ex) The biological domain is not causally self-sufficient
  since nonbiological events (e.g., purely physical events
  such as exposure to strong radiation, natural disasters)
  can cause biological changes.
Exclusion Problem, cont.,
• Now consider circular causation.         Suppose that a mental event M,
    occurring at t, causes a physical event P. From the Causal Closure Principle,
    it follows that there is a physical event, P*, occurring at t, which is a
    sufficient cause of P.

• Kim. This already is an “uncomfortable picture”: Whenever a mental event
    has a physical effect, the physical effect has a purely physical cause as
    well. So there is causal overdetermination (and making the supposed
    mental cause dispensable).

    And consider:

• Causal Exclusion. No event has more than one sufficient cause occurring at
    t—unless it is a genuine case of causal overdetermination.

•   “Unless one opts for the strange view that every case of mental causation
    is a case of causal overdetermination, the exclusion principle must be
    applied to the present case. Since each of M and P* is claimed to be a
    sufficient cause of P, either M or P* must be excluded as a cause of P. But
    which one?”

• Kim: M must go. “The reason is simple: if we let P go, the Causal Closure
    Principle kicks in again, requiring us to posit a physical sufficient cause,
    say P**, for P. (What could P** be if not P*?) And we are off to an
    unending regress….”
DST Response to Kim
• DST has two options:

  (1) Drop causal closure principle.
  (2) Drop notion of circular causation, accepting linear causation
  instead. Saying that higher-level states are realized by complexes
  of physical states, and the physical states really do the casual work.
  (Important: consistent with explanatory import of higher-order

• DST wants first option, but which is one correct? Depends on your
  metaphysical views about the nature of properties.
Debate Over Property Natures (in
• Are property natures a matter of their purely “intrinsic” or internal natures,
   or their causal powers/dispositions? (Lewis vs. Shoemaker).

• Categoricalism/Categorialism: property natures are not determined by any
   causal powers, they are “internal” to the property itself (Armstrong, Lewis).

• Ask: how are fundamental particles taxonomized? By what they do.

• Can property natures really be separated from their causal powers? (What
   would it be like to say that F is a mass property but F does not do what it
   does in our world).

• Dispositionalism: property natures are determined by causal
   powers/dispositions of properties (Schoemaker).
“Dispositionalist” Option
• Suppose property natures are determined by their causal
  powers. Then, microphysical property dispositions could
  determine the causal powers of complexes of particles
  that realize macroscopic brain events that seem to be
  exhibiting “circular causation”.

• In such a case, the causal closure principle is TRUE.
  Physical properties, because they are complexes of
  causal powers, determine the causal powers of the order
  parameter. (The causal power of the order parameter is
  a higher level property that is metaphysically comprised
  of the lower level properties).
Categoricalism: Causal Closure is
False (DST Option)
• Now let’s look at other option. The causal powers of a
  property are irrelevant to property natures.

• In this case, it is difficult to see how (micro)physics is
  causally closed. The laws of microphysics, together with
  the pattern of microphysical properties in a brain,
  wouldn’t determine the brain’s higher-level patterns
  (e.g., that there is a certain order parameter).

• I’m going to take this option. DST thinks it has
  irreducibly higher-level causation. I’ll now apply this
  novel form of causation to the problem of free will.
The Problem of Free Will
• Humans are unique creatures, at
   least relative to other creatures
   on Earth, as we are at a high
   enough stage of intellectual
   development to reflect on
   whether our actions are truly

• We recognize a conflict between
   two perspectives we have on
   ourselves. We see ourselves as
   free agents; yet we also see our
   behavior as being determined by
   underlying causes that we at
   least sometimes are not fully
   aware of.

• Problem of Free Will: Are my
   intentional actions genuinely free,
   or are they determined by laws of
   nature, together with antecedent
   states of my brain?
Why Does the Problem of Free Will
• Free will is associated with a cluster of related themes:
                      • Genuine creativity
                         • Self-control
                         • Self-dignity
        • A sense of desert: we deserve what we get
                          • Autonomy
                     • Moral responsibility
• And related to this, free will is associated with various
  attitudes that we have toward our own and other‟s
  behavior: gratitude, vengefulness, resentment, admiration,
  desire to see them/ourselves punished.
The Deterministic Perspective
• On the other hand, we also view ourselves from various
  impersonal, scientific, or objective perspectives. For

• Our ability to think depends upon the well-being of our
  brains. Aren‟t our decisions to act in a certain way
  determined by the underlying forces at work in our brains?

• A simplified view (not the DST picture): At any time t, the
  configuration of particles in your brain is determined by
  where the particles were located (at t-1), together with the
  laws of physics.
Determinism Defined

• Determinism: Any event is
 determined just in case there are
 conditions (e.g., acts of God, the laws
 of nature, social pressure, states in
 the brain) whose joint occurrence is
 sufficient for the occurrence of the
 event: it must be the case that if
 these conditions jointly obtain, the
 determined event occurs.
Quantum Mechanics
• How can               • Visualization of
 determinism even        wave function of
 aspire to being true    hydrogen atom
 given that
 mechanics says the
 nature of the world
 is indeterministic?
Quantum Mechanics and
• Det: given that event e occurs, event f must occur.

• If QM is true, strictly speaking, determinism is false at the
  quantum level.

• Where does this leave the free will debate?

• Philosophers: not much of a change. The chance of a given
  particle decaying in say, 2 hours, is still “determined” by
  the laws of QM. That is, events are probabilistically
  constrained, or guided by, antecedent conditions, together
  with the laws.
What Position should DST take on
Free Will?

• Suspicion? Would renouncing linear causation as model
    of mental causation dissolve the problem of free will?
•   The problem of free will arises with circular causation
    – Suppose M is a mental event and that further, we act in virtue of
      M, picking up a coffee cup. Further suppose that (as per circular
      causation) M brings about physical event P1 by downward
      causation. P1 then causes the picking up of the cup.
    – The free will problem emerges: Is the happening of M
      determined by the laws of nature, together with antecedent
      events? Or does M somehow “break free” of the laws?
The Sense in Which We Think We
Have “Free Will”
• To answer the question of whether we act freely for DST, we must ask:
   What is genuine free will to begin with? Standard view:

• From a subjective standpoint, we perceive ourselves as free agents who
   are able to influence the world in numerous ways. In many cases, we see
   before ourselves a field of possible actions, out of which, we freely choose

• There‟s a sort of “up to us-ness” associated with our actions: our actions
   are under our control. For any action A, we might have done otherwise.

• S has free will when:
   (a), it is “up to us” what we choose from a field of possibilities
   (b), the origin of our choices and actions is in us and not in
   anyone/anything else over which we have no control.
DST and Free Will
• Suppose DST can give a plausible account of intentional action (e.g.,
   Freeman, Ch. 5, 2000).

• At first blush, this doesn’t limit DST to a certain position on the free will

• An account of intentional action doesn’t require that the actions be
   “genuinely free”; they could be determined. Indeed, DST explains action in
   terms of the evolution of a dynamic system – this sounds sympathetic to a
   kind of determinism.

• On the other hand, most of us think that there is a sense in which some
   actions are free and others are not: e.g., Joe doesn’t act freely when a gun
   is pointing at him, but he does when he picks a vacation spot. A
   neurobiological theory of intentional action should explain such differences,
   giving a sense in which certain actions are free.
Taxonomy of the Positions on the
Debate over Free Will
• There are two primary ways one can be a proponent of Free Will or

• 1. One can be a Compatibilist: Free Will and Determinism are
  compatible with each other.

• 2. One the other hand, one can be an Incompatibilist. In this case,
  either (a), you believe in free will and you don‟t believe in
  Determinism (“Libertarian”); or (b), you believe in determinism
  and reject free will (“Hard Determinism”).

• Argue: DST is incompatible with Libertarianism. Develop a novel
  Compatibilist position for DST: “Neurocompatibilism.”

• (We could also develop a Hard Determinist view).
(Libertarian/Free Will Version)
• “Libertarians”: free will is incompatible with
  determinism. Further, free will exists (thus,
  determinism is false).

• Libertarians often urge that free intentional
  action involves a form of causation that is
  unique to mental causation, and not normal
  event causation (i.e., linear causation).
  Perhaps circular causation is such?
Randomness Problem for
• A major task the Libertarian faces is showing
  that there is a real sense in which there is free
  will that is not compatible with determinism.

• What is it for an event to be an act of free will
  but not determined? Would it be random? Truly
  random events aren’t under the control of
  anyone or anything. How would that be free will
  worth having? No one would be responsible for
  their actions.
Libertarian Reaction
• There are a few ways that the Libertarian reacts to the worry that if events
   aren‟t determined, they are merely random, not giving us true freedom or
   moral responsibility. One is of interest:

• There is a new form of causation by an agent that is not normal event
   causation. This was developed by Rodrick Chisholm, who contrasted
   normal event causation with „agent causation‟ (a special form of causation
   minds employed).

• Big Issue for these theories: We have a physical world of physical causes,
   on the one hand, and a distinct realm, of agent causes, on the other. But
   how do agents causally interact with the physical world of event
   causation? How do our freely willed thoughts enter into the world of
   physical causes and effects? (Like interaction problem with Cartesian

• DST can answer this in a naturalistic way. Introduce circular causation as
   a novel form of causation associated with intentional action. It is not a
   mystery how emergent features effect the microphysical realm. Avoids
   problems with Chisholm‟s account.

 – Is DST really compatible with a Libertarian position? If
   causal closure was violated by mental features there is a
   sense in which one breaks free of physical laws. If
   “Determinism” means “determined by physical laws,”
   then the view is genuinely Libertarian. But if
   determinism means “determined by laws” (including
   special science laws) then the view is Compatibilist. This
   is a more common way of formulating Determinism, and
   was how I formulated it .

 – So: Let‟s see what a Compatibilist DST view looks like.
   (Compatibilism: FW and Det. are compatible).
Problems for Neurocompatibilism

 1. Emergent phenomena in general can
   exhibit downward causation, but,
   intuitively, only minds exhibit free will.

   So, exhibiting downward causation is a
   necessary condition for a system acting
   on the basis of free will, but it is not a
   sufficient condition.
Problems, cont.,
 2. Content of beliefs, desires, etc. are both reasons for
 the action and causes of the action – Davidson, Fodor.

 What are the correlates of concepts according to DST?

 Need these for a DST theory of FW as Compatibilism is
 supposed to accommodate our ordinary framework of
 attribution of blame, praise, etc.
3. Recent Revolution in Free Will
Debate: the work of Benjamin Libet
• - Bigger Problem:              • Now, humans only become
  Neurocompatibilism will          aware of the intention to
  need to deal with Benjamin       act 350-400 msec. after RP
  Libet‟s work on free will.       starts, but still before the
                                   motor act.
• Libet. Freely voluntary acts
  are preceded by a specific
  electrical change in the
  brain (the “readiness
  potential”, RP) that begins
  550 msec. before the act.
  (This is almost the same
  amount of time it takes to
  utter two syllables).
Libet Revolution, cont.
• As Bill Banks and Sue
  Pocket explain: “The issue
  is this. Libet‟s clear-cut
  finding   was     that    his
  subjects consciously and
  freely „decided‟ to initiate
  an action only after the
  neurological preparation to
  act was well under way.
  This implies that the
  conscious decision was not
  the cause of the action.”
Banks/Pockett on Libet, cont.,
• „If conscious decisions are not the cause of
 actions, it follows that we do not have conscious
 free will.     Even worse, because the ability
 consciously to initiate actions is an essential
 property of self, the denial of conscious, personal
 origination of action is a challenge to our sense of
 selfhood. The implication is that we, our
 conscious selves, are not free actors with control
 over our choices in life. We are only conduits for
 unconsciously made decisions. Libet‟s one simple
 experiment has slipped our entire self-concept
 from its moorings.”
Is Compatibilism Dead?
• At first blush at least, this is a clear attack on free
  will, (both the Libertarian and Compatibilist
  versions). Seems to support Hard Determinism.

• The “volitional” process is initiated unconsciously!

• We seem to closely associate consciousness with
  free will, so it seems like this isn‟t a case of free
Carving out a Free Will position?

• Libet is saying that consciousness
 could still control the outcome; it can
 veto the act. So do we have a more
 limited sort of free will?
Libet Revolution, cont.,

• Some say it is only “free wont”. On the other
    hand, if you can veto something, there‟s a sense
    in which for the relevant action that you did not
    veto, you „could have done otherwise‟ (you could
    have vetoed it).
•   For many, free wont will not be sufficient for free
•   Try to do a bit more for Compatibilism.
    Nonconsciously initiated actions can be free.
Libet, cont.,
 Ex) Tennis match with Venus Williams.

 - Did you consciously intend to return her serve before action initiation? No way.

 - As you learned to play tennis, you consciously intended to master actions that, due
 to all your practice, you now initiate involuntarily and non-consciously. So, in a sense,
 the actions are initiated freely. To go back to our def. of FW, “the origin of the choice
 is in you.” It is not as though, contra your purpose in the game, you mysteriously
 initiated a “return the serve” move when you were at the net. Your returning the
 serve is very much a part of you.

 - Although the paradigm cases of free will are conscious ones (ones in the global
 workspace before initiation of motor action); non-consciously initiated actions can be
 acts of free will (in a derivative sense) as we freely chose to develop these skills.

 - They just aren‟t the paradigm cases.

 - Conclusion: Libet‟s results are not contrary to Neurocompatibilism.
• Looked at the novel view that DST has of mental
•   Applied it to FW, noting relation to issue about property
•   Suggested a possible view on FW debate and replied to
    the Libet issue.

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