BOOK I PART IV
ing existences, and appear as such, the notion
of their distinct and continued existence must
arise from a concurrence of some of their qual-
ities with the qualities of the imagination, and
since this notion does not extend to all of them,
it must arise from certain qualities peculiar to
some impressions. It will therefore be easy for
us to discover these qualities by a compari-
son of the impressions, to which we attribute
a distinct and continued existence, with those,
which we regard as internal and perishing.
We may observe, then, that it is neither upon
account of the involuntariness of certain im-
pressions, as is commonly supposed, nor of
their superior force and violence, that we at-
tribute to them a reality, and continued exis-
tence, which we refuse to others, that are vol-
untary or feeble. For it is evident our pains and