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 CHAPTER IX

DEFINITIONS OF PSYCHOLOGY

us resume the study of the preceding ideas in another form. Since, moreover, to define mind is at the same time to define psychology, let us seek for the truth which we can glean from the definitions of this science. Our object is not to discover an exact definition, but to make use of those already existing.

To define psychology is to describe the features of the domain over which this science holds sway, and at the same time to indicate the boundaries which separate it from its neighbours. At first sight this is an affair of geometric survey, presenting no kind of difficulty; for psychology does not merge by insensible transitions into the neighbouring sciences, as physics does with chemistry, for example, or chemistry with biology.

To all the sciences of external nature psychology offers the violent opposition of the moral to the physical world. It cannot be put in line with the physical sciences. It occupies, on the contrary, a position apart. It is the starting point, the most abstract and simple of the moral