98 OF THE ADVANCEMENT OF LEARNING 



their nature, their power, their illusions, either by 

 scripture or reason, is a part of spiritual wisdom. For 

 so the apostle saith, ' We are not ignorant of his strata- 

 gems.' And it is no more unlawful to inquire the 

 nature of evil spirits, than to inquire the force of poisons 

 in nature, or the nature of sin and vice in morality. 

 But this part touching angels and spirits I cannot note 

 as deficient, for many have occupied themselves in it ; 

 I may rather challenge it, in many of the writers 

 thereof, as fabulous and fantastical. 



VII. 1. Leaving therefore divine philosophy or 

 natural theology (not divinity or inspired theology, 

 which we reserve for the last of all as the haven and 

 sabbath of all man's contemplations) we will now 

 proceed to natural philosophy. If then it be true that 

 Democritus said, ' that the truth of nature lieth hid 

 in certain deep mines and caves ' ; and if it be true 

 likewise that the alchemists do so much inculcate, that 

 Vulcan is a second nature, and imitateth that dex- 

 terously and compendiously which nature worketh by 

 ambages and length of time ; it were good to divide 

 natural philosophy into the mine and the furnace, and 

 to make two professions or occupations of natural 

 philosophers, some to be pioneers and some smiths ; 

 some to dig, and some to refine and hammer. And 

 surely I do best allow of a division of that kind, though 

 in more famihar and scholastical terms ; namely, that 

 these be the two parts of natural philosophy, the in- 

 quisition of causes, and the production of effects ; 

 speculative, and operative ; natural science, and 

 natural prudence. For as in civil matters there is 

 a wisdom of discourse, and a wisdom of direction ; 

 so is it in natural. And here I will make a request, 

 that for the latter (or at least for a part thereof) I 

 may revive and reintegrate the misapplied and abused 

 name of natural magic ; which in the true sense is 

 but natural wisdom, or natural prudence ; taken 

 according to the ancient acception, purged from vanity 

 and superstition. Now although it be true, and I know 

 it well, that there is an intercourse between causes and 



