of being overturned by new discoveries in
physiological psychology. We may, indeed, remove from the start the
mistaken fear that a consistent causal aspect of life leads to injustice
to the higher aims and ideal purposes of mankind. If we want to have
psychology,--and that means if we want to consider the mental life in a
system of causes and effects,--we must proceed without prejudices, and
without side-thoughts.

From a psychological standpoint our own mental life and that of our
neighbor, that of the man and that of the child, that of the normal and
that of the insane, that of the human being and that of the animal, are
to be considered as a series of mental objects. They are to be analyzed,
and to be described, and to be classified and to be explained, just as
we deal with the physical objects in the outer world. How are these
objects of the psychologist different from the objects of the physicist,
from the pebbles on the way and the stars in the sky? There is only one
fundamental difference and all other differences result from it. Those
outer objects which we call physical, are objects for everybody. The
star which I see is conceived as the same star which you see, the table
which I touch is the table which you may grasp, too. But every psychical
object is an object for one particular person only. My visual impression
of the star, that is, my optical perception, is a content of my own
consciousness only, and your impression of the star can be a content of
your consciousness only. We both may mean the same by our ideas, but I
can never have your perception and you can never have my perception. My
ideas are enclosed in my mind. I may awaken in your mind ideas which
have the same purpose and meaning, but they are new copies in your mind.
We both may be angry, but your anger can never be my anger, and your
volitions can never enter my mind. Every possible psychical fact thus
exists in one consciousness only, while every physical fact exists for
every possible consciousness.

The psychologist's final task is to explain the appearance and
disappearance, the connections and sequences of these mental objects,
the contents of consciousness. But before he can start on explanation of
the facts, he has to describe them, and describing means analyzing them
into their elements and fixating those elements and their combinations
for an exact report. Such descriptive work is in a way preparatory for
the further task of real expl