ANY book, written as this one is, expressly for use in class-room instruction, must meet one
question with which text-books outside the realm of philosophy are not harassed. What shall
be its attitude towards philosophic principles? This is a question which may be suppressed,
but cannot be avoided. The older works, indeed, were not so much troubled by it, for it is only
recently that psychology has attained any independent standing. As long as psychology was
largely a compound of logic, ethics, and metaphysics, the only thing possible was to serve …

Bacon's dictum regarding the proneness of the mind, in explanation, towards unity and
simplicity, at no matter what sacrifice of material, has found no more striking exemplification
than that offered in the fortunes of psychology. The least developed of the sciences, for a
hundred years it has borne in its presentations the air of the one most completely finished.
The infinite detail and complexity of the simplest psychical life, its interweavings with the
physical organism, with the life of others in the social organism,--created no special difficulty; …