THE LOGICAL STRUCTURE OF SCIENCE 47 



second place, there is the world of nature or fact, upon 

 which these knowing activities are directed; this may be 

 called the subject matter of science. In the third place, 

 there are the actual activities themselves — observing, 

 measuring, experimenting, reasoning, verifying; these taken 

 together and with others constitute the method of the 

 scientist. Finally, there is the result of the activities, the 

 knowledge itself, which may be looked upon as a system of 

 symbols or ideas either held privately by the scientist or 

 communicated freely to others who are cooperating in the 

 enterprise. 



It is a great convenience to be able to speak of these four 

 elements of scientific cognition by means of a terminology 

 which does not create any prejudices as to their essential 

 natures. For this reason they will henceforth be spoken of 

 as the knower, the known, the knowing, and the knowledge. 

 By employing these derivative forms of the verb "to know" 

 one can avoid the risk of assuming that the subject matter 

 of science is a world of matter, or of space-time events, or of 

 sense-data, or of phenomena; or that the method of science 

 is observation, or intuition, or induction, or deduction; or 

 that knowledge is a complex of "psychical ideas," or images, 

 or words, or mathematical symbols. One can talk freely 

 about the elements and the way in which they function in 

 the total situation without attributing to them features 

 which are the result of certain theories of cognition. 



Superficial analysis reveals the general way in which these 

 four elements are structurally united in the cognitive situa- 

 tion. It is primarily a causal complex in which knowledge 

 functions as the effect, and the knower, the known, and the 

 knowing together constitute a complex cause. Roughly 

 speaking, the knower operates upon the known in a manner 

 called knowing to produce knowledge. The complex cause is 

 sufficient to produce the effect, and each of the elements of 

 the cause is necessary. This conception does not assume any 

 specific theory of causal connection but merely that when a 

 knower is confronted with something to be known and sets 



