PREFACE.

attempted to solve only one portion of the grand
problem of Nature; indeed, we suspect that the very
success of their achievements has had a tendency
to discourage, and, consequently, to retard the
solution of the other, and still more interesting
portion of the inquiry.

Nature—we would observe—presents us with
two different—but, in our opinion, correlative—
subjects of investigation—the external universe,
and the percipient mind. All philosophy must be
incomplete if it does not embrace both of these
objects of research. Without a mind to perceive
and comprehend it, no external universe could
exist; and the mind has its peculiar properties as well
as matter.

But in the midst of that scientific regeneration
which has taken place in modern times, philosophy
has become almost entirely one-sided—our attention
is principally, or almost wholly, directed
toward external objects; and the study of the
intelligent and percipient mind, with all its active
energies and passive susceptibilities (psychology),
has been utterly neglected, or even scorned,
amidst the materialistic tendencies of the age. In
short, we would appear to have become incapable
of distinguishing the various accidental modes of
the exercise of our perceptive faculties, occasioned
by the different conditions of our psychical organs,