COMMON SENSE ( AND SCIENCE) 25 



The aim of science is, on the one hand, a comprehension, as com- 

 plete as possible, of the connection between the sense experiences in 

 their totahty, and, on the other hand, the accomphshment of this 

 aim by the use of a minimum of primary concepts and relations. . . . 



Science concerns the totahty of the primary concepts, i.e., concepts 

 directly connected with sense experiences, and theorems connecting 

 them. In its first stage of development, science does not contain any- 

 thing else. Our everyday thinking is satisfied on the whole with this 

 level. Such a state of affairs cannot, however, satisfy a spirit which 

 is really scientifically minded; because the totality of concepts and 

 relations obtained in this manner is utterly lacking in logical unity. 

 In order to supplement this deficiency, one invents a system poorer in 

 concepts and relations, a system retaining [though usually in dras- 

 tically modified form] the primary concepts and relations of the "first 

 layer" as logically derived concepts and relations. This new "second- 

 ary system" pays for its higher logical unity by having . . . elemen- 

 tary concepts (concepts of the second layer), . . . which are no 

 longer directly connected with complexes of sense experiences [that is, 

 these are concepts that refer to "unobservables"]. Further striving for 

 logical unity brings us to a tertiary system, . . . 



Similarities in intent, presuppositions, and subject matter. The 



profound reorientation of its endeavor sharply diflFerentiates science 

 from common sense, but at least three similarities remain significant. 

 A primal biological drive seeks blindly to make past experience 

 the determinant of present action that will succeed. Become self- 

 conscious in common sense, this drive remains active even on those 

 planes of lofty abstraction along which science extends itself as the 

 continuation of common sense. "There is no sharp line between sci- 

 ence and common sense," says Russell, "both involve expectations, but 

 those resulting from science are more accurate." Meyerson urges that 

 "whoever speaks of science speaks of predetermination," and in Sam- 

 bursky's view this much was true even as far back as the Greeks, for 

 he writes that 



then, as now, the task of science was to systematize the sum total of 

 our empirical knowledge in such a way as to make it possible to fore- 

 cast future events. 



This perfectly matches our definition of common sense, but an im- 

 portant redistribution of emphasis will soon be noted. 



Science and common sense share certain "metaphysical presuppo- 



