Februakt 21, 1913] 



SCIENCE 



281 



and how many in our scientific age have 

 observed for themselves? — that the sun- 

 light, when passed through a small square 

 hole, gives a round instead of a square 

 image ; but he explained the fact simply by 

 saying that sunlight has a circular nature. 

 It was centuries before astronomy estab- 

 lished the true explanation in the fact that 

 the sun itself is a circular body. 



It was a combination of the principle 

 sounded like a trumpet-call by Newton — 

 "Abandon substantial forms and occult 

 qualities and reduce natural phenomena to 

 natural laws" — with the modification and 

 improvement of the Baconian method of 

 experimental induction which introduced 

 the new era in the positive sciences of ex- 

 ternal nature. By following these prin- 

 ciples man has made of himself a more 

 accurate and faithful measure of all 

 things; of that which is, how it is; and of 

 that which is not, how it is not. But he 

 still needs as much as ever the further 

 study of himself, as an individual and as 

 a race, in order so to supplement, modify, 

 adapt and otherwise improve the principle, 

 that all the various classes of that accepted 

 and certified knowledge which he calls by 

 the name of science, may benefit by this 

 study. 



I come, therefore, at once to what is the 

 main purpose of this paper. It was an- 

 nounced in the second of the questions 

 proposed at the beginning. This question 

 concerns the more fundamental of those 

 relations in which the stiidy of man stands 

 to all the other positive sciences. Gen- 

 eralizing these relations, I will say that the 

 study of man as the measure of all things 

 is entitled to set forth and expound (1) 

 the method of science; (2) the limitations 

 of science; (3) the ideals of science. And 

 what it is entitled to do for science in gen- 

 eral, it may properly suggest as desirable 



and true for each one of the particular 

 sciences. 



Intelligently comprehended and faith- 

 fully interpreted, the study of man, the 

 measurer, is the only way to find out how 

 his measuring-rod ought to be applied to 

 the different objects which come before 

 him in the different classes of his varied 

 experience. Every positive science, and 

 we might almost say every subdivision of 

 such science, has its special, most satisfac- 

 tory mode of procedure in the search for 

 truth. That this is of necessity so was 

 known to Aristotle as distinctly as it is 

 known to any modern man of science. 

 Indeed, the principle was never better 

 stated than it was by him in the first book 

 of the "Nichomachean Ethics." There 

 the great Greek thinker holds that the mat- 

 ter of a science, i. e., the facts or concep- 

 tions with which it deals, must determine 

 its method or form, according as they 

 admit of being stated with more or less 

 "precision" {'Kicpi0eia). But the Greek 

 word which I have imperfectly translated 

 by the English word ' ' precision ' ' means in 

 Aristotle's use of it a combination of math- 

 ematical exactness, metaphysical subtlety, 

 minuteness of detail and definiteness of 

 assertion. And as applied to the form of 

 science, or study of one aspect of man, 

 namely, the ethical, which he is proposing 

 to consider, he distinctly states that mathe- 

 matical exactness is quite unsuited to 

 ethics; that we must not expect too much 

 subtlety, and that too much detail is to be 

 avoided. In this respect his view is more 

 liberal and more true to the nature, limita- 

 tions and ideals of human science than is 

 that of Sir Isaac Newton when he insists 

 that all "natural phenomena," including 

 the biological, shall be reduced to "mathe- 

 matical laws. ' ' For every step in the evo- 

 lution of science, as subjected to the con- 

 clusions derived from a study of man, 



