COMMENT ⊗   VALID 00002 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00002 00002	Knowing about
C00004 ENDMK
C⊗;
Knowing about

	We can say that someone knows about chemistry or automobiles
or antiques without ourselves knowing about these subjects.  Indeed
we needn't even know the language of the subject.  Hence we cannot
express the statement that someone knows about subject ⊗A by
saying that he knows a certain collection of sentences.

	Moreover, the knowledge about a subject can be expressed
in different ways using different first order languages.  For example,
in describing a simple %2blocks world%1, we may axiomatize the
%2laws of motion%1 using a predicate ⊗on(x,y,s) meaning that
block ⊗x is on block ⊗y in situation ⊗s or we may use a predicate
⊗above(x,y,s) meaning that block ⊗x is above block ⊗y in ⊗s, but
there may be other blocks in between ⊗x and ⊗y.  The same general
facts about the effects of actions and the same particular situations
can be expressed in either language.  Therefore, we would like
a formal notion of %2knowing about%1 that does not depend on a particular
first order language.