Predicates
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In any representational scheme, it is possible to overload a single symbol
with many different meanings. For example, if the state contains the
description of an algebra problem, it might have the concept left used in two
different contexts, to represent expressions on the left side of equal sign
and to represent terms on the left side of another operator, such as plus.
These two different meanings of left are functionally independent.  However,
if both of these are tested in a problem solving episode, the resulting
chunks can contain tests making them dependent.  That is, any tests
concerning the sides of the equation may be dependent on tests of sides of
the operator.  This arises because chunking assumes that if the same
identifier is used in multiple places (in this case, the identifier of the
object with the augmentation ^name left), then a chunk must test that it is
the same, even though in this example it did not have to be the same.  The
appropriate solution to this problem is to create two symbols, possibly
left-expression and left-term.