larry@JPL-VLSI.ARPA.UUCP (12/17/86)
I don't think we need a practioners' and a philosophers' AI discussion list,
but more effort to bring the two types of discussion together. This is such
an effort.
There seems to me to be little gain from giving a Turing Test, which
measures intelligence on a single dimension with a binary scale. Further,
it's only useful after one's work has produced a (hopefully) intelligent
machine, giving little help in the creation of the machine. More useful
would be a test that treated intelligence as a multi-dimensional activity,
somewhat like the various clinical IQ tests but considerably expanded,
perhaps with social or emotional dimensions.
I'd also like to see more microscopic measures, based on my belief that
"higher" intellectual capabilities are composites of essentially independent
capacities. Memory and emotion, for instance, seem to depend upon quite
different mechanisms. (Though in an organism as complex as a human there
may not be any measures that are completely orthogonal.)
Consciousness might be one of those higher capacities, but my guess is that
it is not essential for intelligence. On the other hand, I doubt that
it is an epiphenomenon having no effect on intelligent systems. Perhaps it
serves to integrate what would otherwise be disparate parts working against
their individual and collective survival--in other words, consciousness
insures that there are no orthogonal measures of intelligence!
Before we can investigate (and duplicate) consciousness we first must
investigate the functions on which it depends. One of them is memory, which
seems to come in many varieties. Perhaps the most crucial dimension of
memory (for the study of consciousness) is its volatility. The most
volatile is very short term (a half to one-and-a-half seconds) and seems to
be primarily electrical in nature. Short term memory (15-30 minutes) may be
primarily a chemical phenomenon. Longer term memory seems more related to
biological mechanisms, and seems to come in two types, which I call mid-term
(half-hour to about a day) and long-term. The transfer between mid- and
long-term memory apparently occurs during sleep or sleep-like phenomena.
To relate this to consciousness, I would guess that consciousness is
primarily a function of very-short-term memory but depends in successively
lesser ways on the other volatile memory banks. So to duplicate conscious-
ness we might have to utilize some kind of multi-buffered pipeline memory.
Free will is another of those nebulous ideas that may seem not to relate to
AI practice. I would first say that the connection between freedom and
willing may be spurious. I see others, including machines, making decisions
all the time, so will is obviously a real phenomenon and probably an
indispensable one for intelligence (unlike consciousness). But at least in
machines most decisions are based on information and rules stored in some
kind of memory (with the remaining decisions the result of error). I
surmise that human decisions are similarly determined.
Secondly, some psych research indicates that decisions are rarely (or never)
consciously made. Instead we seem to subconsciously perform a very rapid
vector summation of many conflicting motives (some "rational," some
emotional). Then we decide on motion along the vector (either in a positive
or negative direction), and then create a publicly acceptable reason for our
decision which finally pops up into the conscious. (And most of us are so
quick and skilled at subconscious rationalization that it seems to us as if
the "reason" preceded the decision.) To duplicate/emulate this form of
decision-making analog computation may be more efficient than symbolic
computation.
Larry @ jpl-vlsi.arpa