COMMON BASIS OF EMPIRICISM AND RATIONALISM 23 



must be reached by each thinker through a like process of ascent, 

 it came to be for later antiquity the very type of the hopelessly 

 obscure, and men would say: &quot;As incomprehensible as the Good 

 of Plato.&quot; In his own mind, however, it constituted a new type 

 of absolute certitude, in default of which no genuine knowledge 

 was possible. The supreme conception was reached by an in 

 volved and uncertain process of thought, but when it was thus 

 reached its truth was immediately manifest to reason. The men 

 tal act by which this takes place Plato represents by the analogy 

 of sensuous perception. In contrast to such perception, however, 

 it possessed a mediated immediacy. In a word, it was an intuition. 



This logical theory, w^hich with modifications of greater or less 

 import has persisted down to our own day, descended to modern 

 times by three principal avenues, the teaching of Augustine, 

 that of Aristotle, and that of Plato himself. Aristotle, who gave 

 to the method of working up to first principles the name of induc 

 tion (ejrayoyr}) appears to have thought that it led, not to a single 

 highest conception, but to a variety of first principles peculiar 

 to the various special sciences ; but each when reached was intui 

 tively certain. With Augustine the intuition of self-consciousness 

 first gains the importance which it has had in modern thought. 



It is thus entirely in the spirit of the ancient rationalism that 

 Descartes divides the task of philosophy into two parts: first, 

 a preliminary analysis, the object of which is to discover the 

 necessary fundamental truths; and, secondly, the deduction from 

 these of the system of the sciences. The so-called criterion of 

 truth which he professed to use in order to distinguish genuine 

 from pretended intuitions, is peculiarly significant. The genuine 

 are clear (that is to say, indubitably present to consciousness) 

 and distinct (that is to say, unmistakable in content). In both 

 epithets the analogy of sense-perception is evident; and in both 

 alike the recognition of an absolute beginning is apparent, a 

 beginning which lies beyond proof and beyond external criticism. 

 The evidence of the intuition is entirely in itself. Reflection 

 can do no more than note that it is and what it is. 



