is point open to us. The first would maintain the survival
after death of a recognizable and discrete personality. Another would
suppose a preservation after death, through being taken up into the life
of God. Still another, the theory commonly maintained on the ground of
rationalistic and idealistic metaphysics, would deny that immortality
has to do with life after death, and affirm that it signifies the
perpetual membership of the human individual in a realm of eternity
through the truth or virtue that is in him. But this interpretation
evidently leaves open the question of the immortality of that which is
distinctive and personal in human nature.

[Sidenote: The Natural Science of Psychology. Its Problems and Method.]

Sect. 99. So far we have followed the fortunes only of the "spirit" of
man. What of that lower soul through which he is identified with the
fortunes of his body? When philosophy gradually ceased, in the sixteenth
and seventeenth centuries, to be "the handmaid of religion," there arose
a renewed interest in that part of human nature lying between the
strictly physiological functions, on the one hand, and thought and will
on the other. Descartes and Spinoza analyzed what they called the
"passions," meaning such states of mind as are conditioned by a concern
for the interests of the body. At a later period, certain English
philosophers, following Locke, traced the dependence of ideas upon the
senses. Their method was that of _introspection_, or the direct
examination by the individual of his own ideas, and for the sake of
noting their origin and composition from simple factors. The lineal
descendants of these same English philosophers defined more carefully
the process of _association_, whereby the complexity and sequence of
ideas are brought about, and made certain conjectures as to its
dependence upon properties and transactions in the physical brain. These
are the three main philosophical sources of what has now grown to be the
separate _natural science of psychology_. It will be noted that there
are two characteristics which all of these studies have in common. They
deal with the experience of the individual as composing his own private
history, and tend to attribute the specific course which this private
history takes to bodily conditions. It is only recently that these
investigations have acquired sufficient unity and exclusiveness of aim
to warrant their being regarded as a special science. But suc