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  Commentary on
      Max Velmans, `Is Human Information Processing Conscious'
      Behavioural and Brain Sciences
      C.U.P. 14-4,pp694-695, 1991


                                Aaron Sloman

       Velmans cites experiments undermining hypotheses about causal roles
  for  consciousness  in perception, learning, decision making, and so on.
  I'll leave it to experts to challenge the data, as I want to concentrate
  on removing the surprising sting in the tail of the argument.

       Having argued that consciousness has no functional  role,  he  does
  not  conclude  that  it  is  just  a myth (like the aether). Instead, he
  argues that because there is no  functional  "third-person"  status,  it
  must  be  given some other kind of "first-person" analysis. He also says
  that   `Consciousness   is,   nevertheless,   amenable   to   scientific
  investigation',   and   that   a   complete   psychology   requires  two
  complementary, mutually irreducible, perspectives, one of which  studies

       Curiously,  despite  discussing  subjects'  reports  on   conscious
  episodes,  he does not consider the possibility that the functional role
  might include enabling individuals  to  give  others  information  about
  their  mental  states  (useful  in  many contexts: in the family, in the
  classroom, in the dentist's chair, etc.)

       I won't defend this view because,  as  explained  below,  the  word
  "consciousness"  is  associated with too many muddled ideas for any such
  statement to be worth  defending.  Instead,  I'll  propose  a  different
  approach,  from  an  engineering  standpoint (Dennett's `design stance',
  Dennett 1978).  This views  humans  (and  other  animals)  as  having  a
  complex  and  sophisticated design (which is not to say that there's any
  designer), and attempts to consider how one might  make  something  with
  similar capabilities. Design provision must be made for "consciousness",
  "awareness" etc. (See also Dennett 1983)

       Unfortunately it is not at all  clear  what  this  means.   Because
  "consciousness"  is ill-defined, Velmans says `...it is consciousness in
  the sense of "awareness" that is of primary  concern'.   Is  "awareness"
  any  clearer?   Is  the  fly  aware of my approaching hand? Is a dreamer
  aware of the pain, or the pursuing lion? Most people say:  "Yes,  that's
  why  dreams  are  nice, or frightening." Others might think you can't be
  aware (=  conscious)  when  you  are  asleep  (=  unconscious).  Is  the
  sleepwalker  aware  of the door-handle when he looks at it and turns it?
  We are all aware that the end of the century is approaching. If this  is
  included  in  `the  sense  of  "awareness"'  then consciousness includes
  nearly everything we know. Where are the boundaries?

       Velmans is apparently mainly concerned with  self  awareness,  i.e.
  inwardly  perceiving  one's  internal  states and processes. (Perceiving


  them, not just knowing about them?) There are many situations  in  which
  we  are  self-conscious  or  self-aware  in some way. But not throughout
  waking life: when you are totally absorbed  in  something  outside  you,
  e.g.  watching  an  exciting  football match, or a gripping play, do you
  then lack "first-person" consciousness?

       Conjecture: people who discuss consciousness delude  themselves  in
  thinking  that they know what they are talking about. I don't claim that
  there is nothing they are talking about. Rather,  it  is  not  just  one
  thing,  but  many  different  things  muddled  together. That colloquial
  language uses one noun is no more evidence for a unique  reference  than
  the  multifarious  uses of the word "energy" (intellectual energy, music
  with energy, high energy explosion, etc.)

       Why not, like physicists, ignore colloquial usage and agree on some
  technical  definition of the word "consciousness"?  Partly because there
  is also considerable emotional energy associated with  the  word,  which
  will  interfere  with  serious  usage  of  any  technical  homonym. More
  important, we don't yet have an adequate understanding of the issues: We
  don't  know  what  the  relevant  capabilities of human beings and other
  animals are; we don't know what  functional  decomposition  (i.e.   what
  sort  of architecture) underlies these abilities, and we don't know what
  sorts  of  mechanisms  (electrical,  chemical,  neuronal,  software,  or
  whatever) are capable of producing such functionality.

       Claiming to know what consciousness is by attending  to  it  is  no
  more  convincing  than  claiming  to  know what spatial locations are by
  attending to them. It  didn't  help  Newton.  Attending  doesn't  answer
  questions  about  identity:  "When  is  another thing the same place (or
  mental state) as the one attended to?" has different  answers  depending
  on  what  relationships are in question. A fly, a mouse and a person may
  all be aware of a moving object: Is that the same state?

       There's no answer because there's nothing unique that you have  and
  others  definitely  do or do not have. I am not denying the existence of
  what's attended to -- just its unique identification. Your state is very
  complex and other things may have states that are partly similar, partly
  different. But in what  ways?  How  many  different  substates  underlie
  "conscious"  states?  What  feels  like  something simple that is either
  present or absent, is actually something complex, aspects of  which  may
  be present or absent in different combinations. (This is not a matter of
  degrees, but of kinds of different states.)

       If we give up the idea of a unique referent, we can instead  survey
  relevant  phenomena,  analyse their relationships to other capabilities,
  and then attempt to come up  with  explanatory  designs:  a  hard  task.
  Psychologists,  philosophers,  linguists,  anthropologists,  hypnotists,
  artists, and others can explore, survey,  and  summarise  the  many  and
  varied  phenomena. Cognitive designers can work both bottom-up trying to
  extend existing computational models and  top-down,  trying  to  produce
  detailed  requirements  analyses  and  design specifications for systems
  with  human-like  capabilities.  Then,  after  analysing   the   design-
  tradeoffs,  we  can  try  devising  mechanisms capable of generating all
  these capabilities, including self-monitoring capabilities.

       An architecture that supports not only the perception  of  external
  events  but  also  the  monitoring  of  relatively  global  and abstract
  internal states could have a number of features consistent with the data
  reported by Velmans.

       If sensory mechanisms monitoring the environment can themselves  be


  monitored,  there  will  be a delay between the occurrence of the first-
  order perceptual processes and the results of  second-order  monitoring,
  just  as  there  is a delay between retinal events and the production of
  information about the environment.  Moreover, self-perception, like  all
  perception, will involve errors, loss of information, distortion, and so

       Similarly, some designs support the  ability  to  monitor  "control
  processes"  that take decisions, form plans, initiate actions. Again one
  can expect delay between the  occurrence  of  the  first-order  internal
  events  and the production of high level summary information about those
  events, and perhaps also some distortions and errors.

       It is not surprising that results of monitoring  that  occur  after
  the  events  monitored  cannot be causally involved in their production,
  but they can still have a causal role: informing others, keeping records
  of  internal  processes  for many purposes, including long-term feedback
  that revises  strategies  used  in  first-order  processes.  Experiments
  showing  that  some  kinds  of  learning  occur without high level self-
  monitoring do not imply that all do.

       Another second-order process is high  level  decision  making.  The
  various  subsystems that produce or control actions of various sorts may
  themselves be subject to "meta-level" control. Many parts of the  system
  will  normally chug along on the basis of information available to them.
  But some mechanism is required for coping with conflicting needs and for
  high-level long-term coordination and strategy formation.

       This  might  use  a  "democratic"  voting  system  with   numerical
  summation   and   comparison   procedures   (e.g.   in   neural   nets).
  Alternatively, high-level strategy  formation  and  conflict  resolution
  might   be  reserved  for  a  special  subsystem  with  access  to  more
  information and more powerful reasoning  capabilities  than  the  others
  (Sloman 1978). Mixed modes of global control are also possible.

       Training could also use second-order processes. Many skills require
  low-level  mechanisms to be trained by being taken through various steps
  in a complex process, with fine-tuning based on feedback (e.g.  learning
  to  drive  a  car,  play  the violin, pronounce words). This might use a
  mechanism that does partial analyses of the steps required, then  guides
  the  lower  levels  through those steps, and increasingly lets them take
  control.  Internal monitoring of the behaviour  of  second  (or  higher)
  order  control facilities would require yet another mechanism, alongside
  those monitoring perceptual processing.

       These are but hints at the many and varied ways different levels of
  monitoring   and   control  may  coexist  in  intelligent  agents:  some
  mechanisms controlling others, some  monitoring  others,  some  training
  others,  some  resolving conflicts between others.  Perhaps this somehow
  produces the illusion that there is one high level process in charge  of
  and monitoring everything.

       Conjecture:  This  (very  difficult)  design-based   strategy   for
  explaining  phenomena  that  would  support  talk  of consciousness will
  eventually explain  it  all.  We  shall  have  evidence  of  success  if
  intelligent  machines  of the future reject our explanations of how they
  work, saying it leaves out something terribly important, something  that


  can only be described from the first-machine point of view.


  D.C. Dennett, Brainstorms Bradford Books and Harvester Press, 1978.

  D.C. Dennett, `Intentional systems in Cognitive  Ethology',  Behavioral
  and Brain Sciences, 6(3), 1983.

  A. Sloman The Computer Revolution in Philosophy: Philosophy Science  and
  Models of Mind, Harvester Press, and Humanities Press, 1978.