INDUCTION IN ITS VARIOUS SENSES 41 



of the inductive method that (i) Explanation of the phenomena 

 of physical nature consists in a thorough knowledge of their 

 connexion with their respective causes ; (2) that physical causes 

 act regularly, uniformly ; (3) that, therefore, if we could be sure 

 of having discovered and fixed upon the natural cause of a given 

 phenomenon, amid all its complex surroundings (by a process of 

 abstraction], we could at once (by generalization] formulate the 

 physical law that always and everywhere this cause will act in the 

 same way and produce this same phenomenon. But the difficulties 

 that beset the work of bringing to light with certitude the causal 

 connexion the work of observing, analysing, experimenting, 

 etc. were so great that neither the ancient nor the mediaeval 

 nature-philosophers had the courage and perseverance to grapple 

 with them. Hence, they made little or no serious effort to test the 

 worth of the probable conclusions which they based upon an incom 

 plete enumeration of superficially observed instances. The scientists 

 of the seventeenth and eighteenth centuries, Galileo, Torricelli, 

 Pascal, Descartes, Newton, etc., were making practical efforts in 

 many directions to scrutinize and question physical nature more 

 closely, long before logicians attempted to formulate and interpret 

 the theory of these researches. Lord Bacon s attempt at the 

 conscious formulation of a theory was a failure. Sir Isaac Newton 

 (1642-1727) was conspicuously successful both in theory and in 

 practice. Since the latter s day, many workers, both in the natural 

 and in the mental sciences, have sought to formulate the Theory of 

 inductive research. But those sciences are so progressive in their 

 methods, and views so fundamentally divergent as to the nature 

 of knowledge are propounded by philosophers, that there is still 

 comparatively little uniformity of treatment in the domain of 

 inductive logic. 1 



210. MODERN CONCEPTIONS OF INDUCTION: NEWTON, 

 WHEWELL, J. S. MILL, JEVONS. Newton taught that in the 

 pursuit of knowledge we must start with an analysis of observed 

 facts: that we must suppose and formulate some general law 

 suggested by these facts : that we must, by synthetic or deductive 

 reasoning, derive consequences from this law, thus to determine 

 whether the law coincides with all observed facts or not. 



Indeed, most writers on induction agree in recognizing certain 

 well-defined steps or stages in our progress from particular facts 



1 For varieties of treatment cf. VENN, Empirical Logic, pp. 353 sqq. ; WELTON, 

 op, cit., ii., bk. v., chap. ii. 



