148 ADVANCEMENT OF LEARNING 



referred the investigation of causes to theory, which we again 

 divide into physical and metaphysical; it is necessary that 

 the real difference of these two be drawn from the nature 

 of the causes they inquire into ; and therefore, plainly, phys 

 ics inquires into the efficient and the matter, and meta 

 physics into the form and the end. Physics, therefore, is 

 vague and unstable as to causes, and treats movable bodies 

 as its subjects, without discovering a constancy of causes in 

 different subjects. Thus the same fire gives hardness to 

 clay and softness to wax, though it be no constant cause 

 either of hardness or softness. 6 



&quot;Limus ut hie durescit, et hsec ut cera liquescit 

 Uno eodemque igni.&quot; 7 



&quot;We divide physics into three parts ; for nature is either 

 collected into one total, or diffused and distributed. Nature 

 is directed in its collocations either by the common elements 

 in the diversity of things, or by the unity which prevails in 

 the one integral fabric of the universe. Whence this union 

 of nature produces two parts of physics; the one relating 

 to the principles of things, and the other to the structure 

 of the universe; while the third exhibits all the possible 

 varieties and lesser collections of things. And this latter 

 is like a first gloss, or paraphrase in the interpretation of 

 nature. None of the three are deficient entirely, but how 

 justly and solidly they have been treated is another question. 



The third part we again divide into two others, with re 

 gard to concretes and abstracts, or into physics of creatures 

 and physics of natures: the one inquiring into substances, 

 and all the variety of their accidents; the other into acci 

 dents through all the variety of substances. Thus if in 

 quiry be made about a lion or an oak; these support many 



6 Physics, therefore, may be defined that part of universal philosophy which 

 observes and considers the procedure of nature in bodies, so as to discover her 

 laws, powers, and effects ; and the material origins, and causes thereof, in dif 

 ferent subjects ; and thence from rules for imitating, controlling, or even excel 

 ling her works, in the instances it considers. Shaw. 



* Virgil s Eclogues, viii. 80. 



