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THE POPULAR SCIENCE MONTHLY 



complexity. The phenomena and forces of each science appear in all the 

 sciences which succeed, but not in those which precede, it in the scale. 

 Each science is thus engaged in the study of a new set of forces and 

 phenomena. The order of the sciences here stated is, therefore, the 

 order of increasing complexity and diminishing generality. 



The foregoing classifications of the evolutionary process, forces, phe- 

 nomena and sciences may be resumed in the following table: 



It is not necessary to contend or assert that the forces of the various 

 fields of phenomena, and the consequent extent of the respective sci- 

 ences are, or ever can be, as sharply defined as the foregoing discussion 

 might seem to indicate. The possible overlapping of the fields of phe- 

 nomena and the corresponding sciences should be indicated in the table 

 by an arrangement of braces connecting them. 



Chemistry, physics, biology, psychology and sociology are, then, the 

 five great divisions in a comprehensive classification of the sciences. 

 They are the five great stems or branches out of which all the other 

 and more special sciences necessarily develop. There is no true science 

 which may not be subsumed under one or the other of these general 

 sciences. 



Let us now compare the foregoing classification of the sciences with 

 others, particularly those of Comte and Spencer. Comte's well-known 

 "hierarchy" of the sciences includes the following: mathematics, 

 astronomy, physics, chemistry, biology and sociology. Spencer in- 

 cludes in the concrete sciences astronomy, geology, biology, psychology, 

 sociology and ethics. As already observed, Comte indicated a belief 

 that mathematics is not a true science. It should also be noticed that 

 he gave to biology a wider meaning than is ordinarily ascribed to it. 

 He included what he called " transcendental biology," by which we may 

 understand cerebral biology or psychology. He also, in his later writ- 

 ings, made ethics the final term of the series. His classification needs 

 to be rearranged before a comparison is made. This rearrangement has 

 been made by Professor Ward in a comparison of the classifications of 

 Comte and Spencer. For convenience in comparison, we shall place the 

 classification of Comte, Spencer and the one proposed in parallel 

 columns : 



