46 TWO THEORIES OF KNOWLEDGE 



The Aristotelian view of Nature as an energetic 

 process failed to impress itself upon his successors. 

 Greek Philosophy soon after Aristotle's death de- 

 cayed or was deprived of its early vigour, and the 

 doctrine which survived the wreck was essentially 

 derived, however imperfectly, from the Platonic 

 theory. 



Throughout the first fifteen hundred years of the 

 Christian era this doctrine undoubtedly dominated 

 the course of speculation a speculation of which 

 much is now forgotten and almost as much was 

 certainly barren and unfruitful, but of which we 

 would entertain a very mistaken notion if we were 

 to imagine that it was not often pursued with great 

 subtlety and acumen. 



One natural result of the fact that such a principle 

 dominated human thought was the prevalence of a 

 belief that the explanation of Nature and natural 

 processes could be derived from the cognitive faculty 

 itself. Our cognition of our immediate surroundings 

 was doubtless continuously corrected by immediate 

 practical tests. But the science of a more extended 

 view of Nature was vitiated by this false principle 

 and in consequence for many centuries our whole 

 Knowledge of Nature remained unprogressive and 

 unfruitful. 



Causa cequat effectum, Nature abhors a vacuum, 



