THE CLASSIFICATION OF THE SCIENCES 409 



lems of knowledge — a classification which would be not 

 without value today. Aristotle's threefold division into the 

 theoretical, the practical, and the productive has much 

 to commend it. Though the medieval division into the 

 trivium (grammar, logic, rhetoric) and the quadrivium 

 (geometry, arithmetic, astronomy, music) seems somewhat 

 artificial today, it throws a certain light on the possible 

 affiliations of these studies. Bacon's division into history, 

 poesy, and philosophy, based on the three fundamental 

 "faculties" in man — memory, imagination, and reason — 

 would no longer be accepted in view of the general abandon- 

 ment of the faculty psychology. The classification of Hobbes, 

 which divided studies into those dealing with fact (history) 

 and those dealing with relations between antecedents and 

 consequents (science), offers a suggestive manner of dis- 

 tinguishing between these main types of discipline. Locke's 

 division into physics (knowledge of things), practics (skill 

 of right action), and semeiotics (doctrine of signs) is im- 

 portant in its recognition that the study of symbols is a 

 legitimate and important enterprise. Comte's hierarchy 

 consisting of mathematics, astronomy, physics, chemistry, 

 biology, and sociology is important because of the serial 

 principles employed in its construction; the arrangement 

 exhibits a progressive decrease in generality and an increase 

 in complexity and dependence. The classification of Bliss, 

 which will be examined in a moment, is based upon it. 



For the purposes of more detailed examination, two classi- 

 ficatory schemes have been selected from contemporary 

 writings. One is that of the philosopher, C. S. Peirce, and 

 the other is that of the librarian, H. E. Bliss. These have 

 been selected from a host of candidates for several reasons. 

 The two men are drawn from the contemporary scene, and 

 one may therefore examine their products in the light of 

 the existent sciences. They include in their classificatory 

 schemes not merely the sciences in the narrower sense, but 

 philosophy, history, and the practical arts as well. They use 

 the characteristic modes of classification — the one (Peirce) 



