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.cb THE TRADERS - AN EXAMPLE OF ASYNCHRONOUS ACTIONS


	One of the biggest mysteries in getting an epistemologically
adequate formalism is how to describe asynchronous states, actions
and events.  The following problem presents many of the difficulties
while avoiding difficulties concerned with the treatment of space.

	Several traders communicate with each other by teletype.
Some problems arise when there are just two traders, but the case
of four traders presents most of the problems of which I am
presently aware.  Some of the traders are consumers, some are
producers and some just speculators.  The producers produce the
stuff (call it wheat) from time to time, and have unspecified
expenses from time to time.  The consumers have income and occasionally
want the stuff.  The pure traders want money.

	The messages transmitted are offers to buy and sell,
acceptances and rejections of such offers, announcements that
wheat is available, questions about who has what, and answers
to such questions.  A simplifying assumption is that all questions
are answered truthfully in so far as the answerer has the 
information requested.

	Information about the situation is typically incomplete.
For example, if A sells to B and C sells to D it need not be
defined which event occurs first.
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John McCarthy
Artificial Intelligence Laboratory
Computer Science Department
Stanford University
Stanford, California 94305

ARPANET: MCCARTHY@SU-AI
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