10 PREFACE 



and specious opinions, but to know to a certainty and dem 

 onstration, let him, as a true son of science (if such be his 

 wish), join with us; that when he has left the antechambers 

 of nature trodden by the multitude, an entrance may at last 

 be discovered to her inner apartments. And in order to be 

 better understood, and to render our meaning more familiar 

 by assigning determinate names, we have accustomed our 

 selves to call the one method the anticipation of the mind, 

 and the other the interpretation of nature. 



We have still one request left. We have at least re 

 flected and taken pains in order to render our propositions 

 not only true, but of easy and familiar access to men s 

 minds, however wonderfully prepossessed and limited. 

 Yet it is but just that we should obtain this favor from 

 mankind (especially in so great a restoration of learning 

 and the sciences), that whosoever may be desirous of form 

 ing any determination upon an opinion of this our work 

 either from his own perceptions, or the crowd of authori 

 ties, or the forms of demonstrations, he will not expect to 

 be able to do so in a cursory manner, and while attending 

 to other matters; but in order to have a thorough knowledge 

 of the subject, will himself by degrees attempt the course 

 which we describe and maintain; will be accustomed to the 

 subtilty of things which is manifested by experience; and 

 will correct the depraved and deeply rooted habits of his 

 mind by a seasonable, and, as it were, just hesitation: 

 and then, finally (if he will), use his judgment when he 

 has be^un to be master of himself. 



