OF KNOWLEDGE. 321 



certainty and light. He recognised that certainty in the 23. 

 highest sense of the word implies trust and confidence, constructive 



effort. 



In the then prevailing insecurity of external conditions 

 and the strife of political and religious parties, such 

 certainty could according to him be found by the indi- 

 vidual thinker only through retiring into the depths of 

 his own mind and seeking there for a central fact or 

 self-evident principle from which to start. This he 

 found in the process of thought itself. But Thought 

 implies a thinking Subject ; it gave him besides an indica- 

 tion how to proceed further in the search for truth and 

 certainty by suggesting an inquiry into the method of 

 thought and into its content. As to the former he was 

 led to fix upon the mathematical methods, inasmuch as 

 they lead to clearly defined conceptions which bear 

 intuitive or immediate evidence of their truth. But 

 human thought is also characterised by the fact that it 

 leads beyond itself, i.e., beyond the limit of the finite 

 thinking subject. Applying the idea of causality, 

 Descartes comes to the conclusion that what we now 

 term the transcendency of thought cannot have its 

 foundation in the thinking subject alone, but implies the 

 existence of a higher intellect which he identifies with 

 the Divine Mind. In this manner he finds the way out 

 of the limits of subjective thought to a belief in another 

 reality and into that of external things. In contradis- 

 tinction to the immediate evidence of the subjective 

 mind, the nature of which is thought, the nature of the 

 objective world consists in extension, i.e., in the mathe- 

 matical properties of number and measure. Descartes 

 thus establishes the contrast or dualism of a thinking 

 VOL. in. x 



