404 



PHILOSOPHICAL THOUGHT. 



important works which deal with this subject since the 

 age of Mill in England and the return to Kant in 

 Germany. But it is hardly from a philosophical point 

 of view — i.e., from the point of view of the theory of 

 knowledge as such — that the more important investiga- 

 tions have been undertaken, or that the great revolution 

 regarding the aspect of the problem of knowledge is 

 being prepared. This has been done in the interests of 

 science itself, which everywhere has been brought face 

 to face with fundamental problems, having outgrown 

 the language and terms in which it was clothed a 

 hundred years ago. With the intention of providing 

 more suitable expressions, more elastic notions, and 

 wider principles, some of the foremost scientific thinkers 

 have, within the last fifty years, attacked the funda- 

 mental conceptions with which science operated in their 

 time. This I showed, at sufficient length, in the first 

 part of this History,-^ where the leading principles of 

 modern science were discussed, and the different stages 



of Science ' (1892), in which he re- 

 fers to Kirchhoff and Mach, and 

 develops independently correcter 

 notions of the principles of science ; 

 following on the lines indicated in 

 this country by Mill and Stanley 

 Jevons on the one side, by Clerk 

 Maxwell and Clifford on the other. 

 French literature, after having in 

 the early years of the century, 

 notably under the influence of 

 Lagrange and later on through 

 Poncelet and Carnot, contributed 

 so largely to the clearing up of the 

 principles of pure science, has 

 quite recently produced two origi- 

 nal works on the subject b}' M. 

 Henri Poincare, entitled ' La 

 Science et I'Hypothese' (1903 and 

 1905). But it should also be 



noted that already in his ' Essais 

 de Critique G^nerale ' Renouvier 

 gave some very clear and correct 

 definitions of fundamental mechani- 

 cal principles, at a time when both 

 in Germany and in this country 

 the notions on this subject were 

 still generally in a state of great 

 confusion. 



1 I shall return to this subject 

 in a later cliapter, which will deal 

 not so much with the leading 

 principles of scientific research as 

 with the philosophical problem of 

 nature, i.e., with the various 

 attempts to comprehend the total- 

 ity of things as revealed to us by 

 our outer senses, — what we may 

 term the cosmological problem. 



