If there is any order of phenomena that is unequivocally worthy
of being c^tA psychological^ it is the facts of consciousness. But
consciousness presupposes for its production definite organic con-
ditions. If they do not exist, there is no consciousness ; and
when they disappear, consciousness is at an end. And it may be
remarked, that as regards the brain, consciousness does not stand
in any vague, general relations. Though physiologists still debate
as to whether the important point in the brain, considered as a
psychological organ, is its weight, or its chemical constitution, or
the number of its convolutions, or its form, or its type, it is likely
that each of these conditions possesses a special importance of its
own. Thus, it may be afArmed that an adult human brain weigh*
ing le» than two pounds induces that mental state which we call
idioqr.
174 Heredity.
