"CAN SCIENCE EXPLAIN INTENTIONALITY?"
Boston Colloquium for Philosophy of Science
Boston University
December 8, 1997
Summarized by Paul H. Carr

The conference brought together philosophers and neuroscientists. The final speaker, Tien Yu Cao, Boston University, answered the question as "no," if science is defined narrowly, and a qualified "yes," if science is defined more broadly.

What is intentionality and consciousness ?

Thomas Acquinas defined intentionality as the process by which a person stretches forth (reaches out), acts on his environment and, as a result learns and changes within.

Merleau-Ponty ("Phenomenology of Perception," 1962) defined intentionality as the process by which "the world shapes our brain and we shape the world."

The ordinary meaning of "intentionalality," i.e. determining to do something specific, is a subset of this broader, philosophical definiton.

The lead speaker, Karl Pribram, M.D., Stanford University Emeritus, defined intentionality as "the perceiver as distinguished from what is perceived." It is characterized by nonlinear processing in the brain which breaks the time-reversal symmetry of a linear process. When we make a decision, such as whom we marry, there is no reversing this life changing process.

Pribram defined "consciousness" as the monitoring or awareness of brainís activity. Freudís "unconscious," "preconscious," and "conscious" mind express the degrees of our awareness.

Mental Representation??

Pribram argued in favor of mental representation, while Hubert Dreyfus, philosopher, UC Berkeley, argued against. Pribram said: "We must have mental representation or we canít explain anything." The representation of a human face in the brain is not identical to the face. The anatomy and structure of a piano is different from the music.

Dreyfus argued against in his talk "Merleau-Pontyís Critique of Mental Representation.". "Skills are Ďstored,í not as representation in the mind, but as dispositions to respond to the solicitations of situations in the world." This is illustrated by the following structure of skill acquisition:

  1. Novice: A. Features and B. Rules
  2. Advanced Beginner: A. Aspects and B. Maxims (Polanyi)
  3. Competence: A. Nuanced perception of Goals and Actions Emotions are embedded with learning and problem solving (Demasio)
  1. Proficient: A. Involved, immersed and perceptive but  A. Needs time to deliberate and decide
  1. Expertise: A. Rapid intuition without time for analysis                                                           B. Doesnít need a mental representation of the goals, but is keenly aware of the total situation or "gestalt."  When Larry Bird receives the basketball, hepasses it intuitively, and then thinks about what he did..                                                                                                                                                                                                               The programming of "neural networks" simulates intuitive expertise. In such models, memories of specific situations are not stored. Rather, the connections between "simulated neurons" are modified by successful behavior in such a way that the same input will produce the same or similar output. Neural nets are well suited at pattern recogintion.
During the discussion, Polanyiís "Tacit Dimension" was mentioned. Dreyfus said: "Polanyi is phenomenologically correct, but I donít agree with his rules."

(Note added after the meeting: The example of the victory of BIG BLUE over world-chess champion. BIG BLUE was not programmed with neural nets. Each play was analyzed in terms of a large number of possible responses. The decision of the actual move was made by the use of maxims, derived from an analysis of championship chess games. The "jury may still be out" on the issue of mental representation. The expert may have subconscious mental representations.)

SUMMARY:

Meaning can not be separated from the nature of perception. Intention is the dynamic process by which we update our perception of the world. The brain is plastic and adaptable and is shaped by society and culture. It also gets reprogramed. When one part of the brain is damaged, other parts get reprogrammed to accomplish the functions of the damaged part. Social animals have bigger brains for communication. We humans view the world in terms of causality. The cause is how we act on the world. The effect is reaction of the world back onto us. Science is correlative, not cause and effect.