Instituut voor Taal- en Kennistechnologie
Institute for Language Technology and Artificial Intelligence
There are several ways to construe Kentridge's friendly suggestions
about chaos and cognition; some are indeed supportive, but some may be
Trojan horses! It all boils down to which of the three rooms in the
three-room argument his arguments apply to: If nonlinear dynamical
systems that display chaos have essential analog properties (analogous
to essential parallelism, as in room one, PAR, if a chaotic system is,
like a transducer or a furnace, something a system has to be
in order to display certain properties essential to cognition (in
other words, if symbolically/numerically simulated chaos, ``virtual''
chaos, won't do), then all we need is the demonstration that such an
essential property of chaos is indeed also a property essential to
cognition. Transduction had face validity, but chaos requires an
argument or a proof (I'm not sure I see either in Kentridge's
commentary, but perhaps I have not understood it fully).
On the other hand, if all the performance properties of chaos
could also be exhibited by room 2 (SIM), which would now be a
symbolic/numerical simulation of the chaotic system in room 1 (i.e., a
``nondeterministic symbolic description of the neural network's
behavior,'' perhaps using numerical probabilities, multiplicative
interactions, even pseudo-random number generators), then we would of
course be back where we were in the beginning.
My own approach has the virtue of not stipulating anything about the
innards of the winning system except that it must include sensorimotor
transduction, which is of necessity analog. I can't tell whether
Kentridge's proposal pertains only to properties of the innards (a
nonlinear dynamical system with the capacity to exhibit chaos), or
also to the properties of the analog input itself (in which case our
positions are even more compatible). One still waits, of course, to
see the full performance capacity of chaos (whether simulated or
real): Can it, for example, help us pass the TTT?