AUTHOR'S PREFACE. 



The present study of the monistic philosophy is 

 intended for thoughtful readers of every condition 

 who are united in an honest search for the truth. 

 An intensification of this effort of man to attain a 

 knowledge of the truth is one of the most salient 

 features of the nineteenth century. That is easily 

 explained, in the first place, by the immense progress 

 of science, especially in its most important branch, 

 the history of humanity. In the second place, we 

 must trace it to the open contradiction that has 

 developed during the century between science and the 

 traditional " Revelation " ; and, finally, to the inevit- 

 able extension and deepening of the rational demand 

 for an elucidation of the innumerable facts that have 

 been recently brought to light, and for a fuller know- 

 ledge of their causes. 



Unfortunately, this vast progress of empirical 

 knowledge in our " Century of Science " has not been 

 accompanied by a corresponding advancement of its 

 theoretical interpretation — that higher knowledge of 

 the causal nexus of individual phenomena which we 

 call philosophy. We find, on the contrary, that the 

 abstract and almost wholly metaphysical science 

 which has been taught in our universities for the 



