ii DESCARTES AND BRUNO 335 



thought. Bruno indeed begged men to throw over all 

 prejudices, all traditional beliefs, before entering upon 

 the study of nature : he agreed with Descartes there- 

 fore in rejecting wholly every authority but that of 

 man's own reason, in demanding complete freedom of 

 thought, not only from outward, but also from inward, 

 subjective fetters. Most nearly he approaches the 

 " Cartesian doubt " in the preface to the Articuli 

 adv. Mathematicos. 1 " As to the liberal arts, so far from 

 me is the custom or institution of believing masters or 

 parents, or even the common sense which (by its own 

 account) often and in many ways is proved to deceive 

 us and lead us astray, that I never settle anything in 

 philosophy rashly or without reason ; but what is 

 thought perfectly certain and evident, whenever and 

 wherever it has been brought into controversy, is as 

 doubtful to me as things that are thought too difficult 

 of belief, or too absurd." But this is still very far from 

 the universal doubt of Descartes, doubt, not of this 

 or that particular opinion or belief, but of all possible 

 beliefs. Bruno's aim was knowledge, to add to or correct 

 the sum of general opinion as to the world as a whole, 

 as to man's relation to it and to God ; Descartes' was 

 certainty ', to find a basis from which a system of thought 

 might be built up de novo, and from which at the same 

 time a secure ground for morality and religion might be 

 derived. The doubt was nothing without the certainty 

 to which it led, the certainty of self-consciousness, 

 which, as it has been said, is only the other side, the 

 positive expression of the universal doubt itself. On 

 the other hand, in the subsequent steps of the Cartesian 

 philosophy, the arguments on the nature of God, and 

 the relation of the infinite to the finite substances, many 



1 Op. Lot. i. 3. 4. 



