EMPIRICAL TOOLS AND EMPIRICISM 169 



ward facts may on occasion be tvisely ignored; and, in making a be- 

 ginning, irreducibly vague concepts prove often immeasurably su- 

 perior to logically impeccable categories that presuppose all need for 

 investigation is at an end. An obsessive concern with methodological 

 chastity does not often eventuate in scientific fecundity. 



Great scientists practice not Method but success. Determined to 

 get on with his difficult job, however best he can, the working scien- 

 tist, in Einstein's words, 



. . . must appear to the systematic epistemologist as a type of un- 

 scrupulous opportunist: he appears as realist insofar as he seeks to 

 describe a world independent of the acts of perception; as idealist 

 insofar as he looks upon the concepts and theories as the free inven- 

 tions of the human spirit (not logically derivable from what is em- 

 pirically given ) ; as positivist insofar as he considers his concepts and 

 theories justified only to the extent to which they furnish a logical 

 representation of relations among sensory experiences. He may even 

 appear as Platonist or Pythagorean insofar as he considers the view- 

 point of logical simplicity as an indispensable and eff^ective tool of his 

 research. 



The growth of the natural sciences utterly defies reduction to 

 Method, to the constellation empiricism-fact-logic. I have distin- 

 guished the empirical and conceptual lobes of the heuristic apparatus 

 to facilitate discussion, and because between them there is all the 

 distinctness of facts from ideas. But ultimately we find the facts in- 

 separable from the ("subjective") ideas with which we seek, recog- 

 nize, express, and appraise the relevance of ("objective") facts. Then 

 strikes the hour to move on beyond empiricism: however large it 

 looms in the history of science, Langer accurately remarks the some- 

 thing else that looms still larger. 



The limits of thought are not so much set from outside, by the ful- 

 ness or poverty of experiences that meet the mind, as from within, by 

 the power of conception, the wealth of formulative notions with 

 which the mind meets experiences. ... A new idea is a light that 

 illuminates presences which simply had no form for us before the 

 light fell on them. 



