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C00002 00002		In the case of a specific known machine, one can often give a
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	In the case of a specific known machine, one can often give a
%2first  order  structural  definition%1.    Thus  we  might  give  a
predicate %2B(s,p)%1 such that if the  machine is in state %2s%1,  it
is said to  believe the sentence  %2p%1 provided %2B(s,p)%1  is true.
However, I don't think there is a general definition of belief having
this form that applies to all machines in all environments.

	Therefore we give a %2second order predicate%1  β%2(B,W)%1 that
tells whether we regard the  first order predicate %2B(s,p)%1 as a
"good" notion  of belief in the %2world W%1.  Such a predicate β will
be  called a  %2second  order  definition%1; it  gives  criteria  for
criticizing   an  ascription  of   a  quality   to  a  system.
Axiomatizations of  belief  give   rise  to  second   order
definitions, and we suggest that both our  common sense and scientific
usage  of not-directly-observable qualities  corresponds more closely
to second  order structural  definition than  to any kind of behavioral
definition.   It  should  be  noted that  a  second order  definition
cannot  guarantee  that  there exist  predicates  %2B%1  meeting the
criterion β or that such a %2B%1 is unique.   It can  also  turn  out
that  a quality is best defined as a member of a group of related
qualities.

	The  second   order   definition  criticizes   whole   belief
structures rather than  individual beliefs.  We can  treat individual
beliefs  by  saying  that a  system  believes  %2p%1  in state  %2s%1
provided all "reasonably good"  %2B%1's satisfy %2B(s,p)%1.  Thus  we
are distinguishing the "intersection" of the reasonably good %2B%1's.