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∂CSL Professor Dana Scott↓Sub-faculty of Philosophy↓l0 Merton Street 
↓Oxford University↓Oxford England∞

Dear Dana:

	Some time in the 60's you gave a formulation of list processing
in the λ-calculus analogous to LISP.  I think I remember that
T was %2λx_y._x%1, F was %2λx_y._y%1 and the conditional expression
%2if_p_then_a_else_b%1 was %2p(a)(b)%1, but I can't remember or
reconstruct how lists were handled.  Do you have a copy of the
memo or do you remember how you did it?

	I would be interested in any views you might have
on non-monotonic reasoning.  Enclosed is a reprint of my paper in
the recent special issue of %2Artificial Intelligence%1 on the
subject.  Since I wrote it, I have been trying to apply the
ideas to concepts as well as objects.  One goal is to formalize
the slogan %2"Ceteris paribus, de re = de dicto"%1, i.e. to
express in some logical language the idea that the distinction
is ordinarily unnecessary so that ordinary language is efficient
in requiring circumlocution to express it.

.reg