THE NATURE OF THE SOUL. 103 



In Germany, Wilhelm Wundt of Leipzig is con- 

 sidered to be the ablest living psychologist ; he has 

 the inestimable advantage over most other philo- 

 sophers of a thorough zoological, anatomical, and 

 physiological education. Formerly assistant and 

 pupil of Helmholtz, Wundt had early accustomed 

 himself to follow the application of the laws of 

 physics and chemistry through the whole field of 

 physiology, and, consequently, in the sense of 

 Johannes Miiller, in psychology, as a sub-section 

 of the latter. Starting from this point of view, 

 Wundt published his valuable " Lectures on human 

 and animal psychology " in 1863. He proved, as he 

 himself tells us in the preface, that the theatre of the 

 most important psychic processes is in the " uncon- 

 scious soul," and he affords us "a view of the 

 mechanism which, in the unconscious background 

 of the soul, manipulates the impressions which arise 

 from the external stimuli." What seems to me, 

 however, of special importance and value in Wundt' s 

 work is that he "extends the law of the persistence 

 of force for the first time to the psychic world, and 

 makes use of a series of facts of electro-physiology by 

 way of demonstration." 



Thirty years afterwards (1892) Wundt published a 

 second, much abridged, and entirely modified edition 

 of his work. The important principles of the first 

 edition are entirely abandoned in the second, and the 

 monistic is exchanged for a purely dualistic stand- 

 point. Wundt himself says in the preface to the 

 second edition that he has emancipated himself from 

 the fundamental errors of the first, and that he 

 " learned many years ago to consider the work a 

 sin of his vouth"; it "weighed on him as a kind of 



