It is therefore very natural for us to mistake the one for the other.
[Footnote 9 This reasoning, it must be confest, is somewhat abstruse, and difficult to be comprehended; but it is remarkable, that this very difficulty may be converted into a proof of the reasoning.

We may observe, that there are two relations, and both of them resemblances, which contribute to our mistaking the succession of our interrupted perceptions for an identical object.

The first is, the resemblance of the perceptions: The second is the resemblance, which the act of the mind in surveying a succession of resembling objects bears to that in surveying an identical object.

Now these resemblances we are apt to confound with each other; and it is natural we shoud, according to this very reasoning.

But let us keep them distinct, and we shall find no difficulty in conceiving the precedent argument.] The persons, who entertain this opinion concerning the identity of our resembling perceptions, are in general an the unthinking and unphilosophical part of mankind, (that is, all of us, at one time or other) and consequently such as suppose their perceptions to be their only objects, and never think of a double existence internal and external, representing and represented.