[net.ai] complexity of formal systems

WILKINS@SRI-AI.ARPA (12/05/83)

From:  Wilkins  <WILKINS@SRI-AI.ARPA>

  From: Steven Gutfreund <gutfreund%umass-cs@CSNet-Relay>
  They then resort to arcane languages and to attributing 'mental'
  characteristics to what are basically fuzzy algorithms that have been applied
  to poorly formalized or poorly characterized problems.  Once the problems are
  better understood and are given a more precise formal characterization, one
  no longer needs "AI" techniques.

I think Professor McCarthy is thinking of systems (possibly not built yet)
whose complexity comes from size and not from imprecise formalization.  A
huge AI program has lots of knowledge, all of it may be precisely formalized
in first-order logic or some other well understood formalism, this knowledge
may be combined and used by well understood and precise inference algorithms,
and yet because of the (for practical purposes) infinite number of inputs and
possible combinations of the individual knowledge formulas, the easiest
(best? only?) way to desribe the behavior of the system is by attributing
mental characteristics.  Some AI systems approaching this complex already
exist.  This has nothing to do with "fuzzy algorithms" or "poorly formalized
problems", it is just the inherent complexity of the system.  If you think
you can usefully explain the practical behavior of any well-formalized system
without using mental characteristics, I submit that you haven't tried it on a
large enough system (e.g. some systems today need a larger address space than
that available on a DEC 2060 -- combining that much knowledge can produce
quite complex behavior).