SECTION D METHODOLOGY OF SCIENCE 



(Hall 6, September 22, 3 p. m.) 



CHAIRMAN: PROFESSOR JAMES E. CREIGHTON, Cornell University. 

 SPEAKERS: PROFESSOR WILHELM OSTWALD, University of Leipzig. 



PROFESSOR BENNO ERDMANN, University of Bonn. 

 SECRETARY: DR. R. B. PERRY, Harvard University. 



ON THE THEORY OF SCIENCE 



BY WILHELM OSTWALD 

 (Translated from the German by Dr. R. M. Yerkes, Harvard University) 



[Wilhelm Ostwald, Professor of Physical Chemistry, University of Leipzig, 

 since 1887. b. September 2, 1853, Riga, Russia. Grad. Candidate Chemistry, 

 1877; Master Chemistry, 1878; Doctor Chemistry, Dorpat. Dr. Hon. 

 Halle and Cambridge; Privy Councilor; Assistant, Dorpat, 1875-81; 

 Regular Professor, Riga, 1881-87. Member various learned and scientific 

 societies. Author of Manual of General Chemistry; Electro Chemistry; Foun- 

 dation of Inorganic Chemistry; Lectures on Philosophy of Nature; Artist's 

 Letters; Essays and Lectures; and many other noted works and papers on 

 Chemistry and Philosophy.] 



ONE of the few points on which the philosophy of to-day is united is 

 the knowledge that the only thing completely certain and undoubted 

 for each one is the content of his own consciousness; and here the 

 certainty is to be ascribed not to the content of consciousness in 

 general, but only to the momentary content. 



This momentary content we divide into two large groups, which 

 we refer to the inner and outer world. If we call any kind of content 

 of consciousness an experience, then we ascribe to the outer world 

 such experiences as arise without the activity of our will and cannot 

 be called forth by its activity alone. Such experiences never arise 

 without the activity of certain parts of our body, which we call 

 sense organs. In other words, the outer world is that which reaches 

 our consciousness through the senses. 



On the other hand, we ascribe to our inner world all experiences 

 which arise without the immediate assistance of a sense organ. 

 Here, first of all, belong all experiences which we call remembering 

 and thinking. An exact and complete differentiation of the two 

 territories is not intended here, for our purpose does not demand 

 that this task be undertaken. For this purpose the general orienta- 

 tion in which every one recognizes familiar facts of his consciousness 

 is sufficient. 



Each experience has the characteristic of uniqueness. None of us 

 doubts that the expression of the poet " Everything is only repeated 

 in life " is really just the opposite of the truth, and that in fact no- 



