CONCLUSION 219 



gall. Therefore animals without gall are long-lived." 

 The opposition between induction and deduction, which 

 has been pointed out in modern times, is not, according 

 to Aristotelianism, founded upon nature. The unity 

 of the two perspectives, which, from the standpoint of 

 critical reflection, appear incompatible, is, according to 

 Aristotle, ensured by the inversion of the order of pro- 

 gressively acquired knowledge and the order of nature, 

 " between order as it appears to us and order in itself." 

 According to a remarkable saying of the Nicomachean 

 Ethics (1112 b 23), " To eayaxov ev rfj avaXvoec, tzqcotov 

 iv rfj yeveasi." x The aim of the sciences which are 

 based on sensible observation is thus to discover the 

 classification and natural hierarchies of phenomena in 

 relation to one another. Their main work is to group 

 extensively and comprehensively the conceptions to 

 which these phenomena correspond. The physical 

 causality which justifies this grouping is imbued with 

 finality and cannot admit absolute quantitative 

 relations, except in rare cases. 



For the Greeks there existed a cleft between the 

 mathematical sciences and the physical or natural 

 sciences, and in their opinion this cleft could never be 

 closed up. The reason appears to be as follows. 



The sciences whose data are exclusively provided by 

 sensation are concerned with bodies which, with the 

 exception of the heavenly bodies, are subject to birth, 

 death, and compulsory motion. These bodies, besides, 

 obey a cause which displays its effects in time by virtue 

 of the finality inherent in nature. As individuals they 

 never realize, except imperfectly, the form towards 

 which they aspire. Consequently, between form and 

 matter, there cannot exist an adequate relation, 

 mathematically measurable, and from a logical point 

 of view there are always obscurities. Doubtless 



1 L. Brunschvicg, Experience humaine et causalite',,p. 157. 



