BOOK I PART IV
idea by an act or operation of the mind, sim-
ilar to that by which we conceive the other.
This circumstance I have observd to be of great
moment; and we may establish it for a gen-
eral rule, that whatever ideas place the mind
in the same disposition or in similar ones, are
very apt to be confounded. The mind readily
passes from one to the other, and perceives not
the change without a strict attention, of which,
generally speaking, it is wholly incapable.
In order to apply this general maxim, we
must first examine the disposition of the mind
in viewing any object which preserves a per-
fect identity, and then find some other object,
that is confounded with it, by causing a similar
disposition. When we fix our thought on any
object, and suppose it to continue the same for
some time; it is evident we suppose the change