THE CHALLENGE TO THE TRADITIONAL IDEAL OF SCIENCE 451 



of the intelligence. The mechanical explanation becomes the only 

 conceivable type of scientific explanation.^ 



Descartes' generic notion of science does, however, retain many 

 of the traditional elements, although deduction is regarded 

 rather as a string of intuitions, and induction as a kind of care- 

 ful inventory of simple elements; the universe is still regarded 

 as a cosmos, but not in virtue of his philosophical appreciation 

 of order and diversity. The direct object of science is presented 

 as the ideas of the mind, and their correlation with external 

 reality can be assured only by illegitimate appeals to the vera- 

 city of God as author of nature, and to the principle of 

 causality. Once such appeals were shown to be illogical, and 

 Hume was to show how easily this could be done, if it were 

 granted that the direct object of knowledge is an idea, not only 

 could it no longer be maintained that the universe is a cosmos, 

 but it would follow that the mind could not know reality as it 

 is in itself. The full fruits of the revolution started by Descartes 

 would become apparent only in the critiques of Kant. 



In his preface to a well-known work by G. Gurvitch,* Leon 

 Brunschvicg makes some interesting reflections on the relation 

 between Descartes and Kant. He maintains that Kant, and 

 after him, German philosophy generally, did not perceive the 

 import of the classical rationalism of Descartes, which provided 

 a system of reference for placing problems about reason, by 

 clearly formulating the methodology of modern science, as 

 based upon the new mathematical physics. The mental process 

 employed in the new science, he argues, has nothing in common 

 with Aristotelian deduction or Euclidian intuition; it is not a 

 movement from universal to particular, or from concrete to 

 abstract, but from the simple to the complex. It seeks to 

 equate problems, and to solve them by algebraic composition. 

 Basing itself on an elementary equation, it attains to a vision 

 of cosmic phenomena as a unified whole. Thus the realism of 

 the intelligible world gives way to the dynamism of the intel- 



^ Three Reformers (London: Scribner, 1929), p. 73. 



* Les Tendances ActueUes de la philosophie Allemande (Paris, 1949) , pp. 3-8. 



