CHAP. IV. J THE BRANCHES OF PHYSICS DISCRIMINATED. 123 



\Ve have assigned the common and promiscuous axioms of 

 the sciences to primitive philosophy ; and all relative and 

 accidental conditions of essences, which we call transcend ant, 

 as multitude, paucity, identity, diversity, possible, impossible, 

 and the like, we have included in the same province, with 

 this understanding, that they be handled according to their 

 effects in nature, and not logically. We have referred the 

 inquiry concerning God, unity, goodness, angels, and spirits, 

 io natural philosophy. But to assign the proper oflicc of 

 metaphysics, as contradistinguished from primary philosophy, 

 mid natural theology, we must note, that as physics regards 

 the things which are wholly immersed in matter and move- 

 able, so metaphysics regards what is more abstracted and 

 fixed \ that physics supposes only existence, motion, and 

 natural necessity, whilst metaphysics supposes also mind and 

 idea. But to be more express : as we have divided natural 

 philosophy into the investigation of causes, and the pro 

 duction of effects, and referred the investigation of causes 

 to theory, which we again divide into physical and meta 

 physical ; it is necessary that the real difference of these two 

 be drawn from the nature of the causes they inquire into , 

 and therefore, plainly, physics inquires into the efficient and 

 the matter, and metaphysics into the form and the end. 

 Physics, therefore, is vague and unstable as to causes, and 

 treats moveable 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. 1 



&quot; Liinus ut hie durescit, ct hoec ut cera liquescit 

 Uno codemquc igni.&quot; t 



We divide physics into three parts ; for nature is cither 

 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 



f 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 etfects ; and the material origins, and 

 causes thereof, in different subjects ; and thence form rules (or imi- 

 latino, controlling, or even ejcceiiinj her works, in the instances it 

 cutideiH. i&aw. * Virgil s Eclogues, viii. 80. 



