40 NOVUM ORGANUM 



urable composition, or at any rate neglect to advance 

 by greater and more diligent observation to the third 

 and fourth qualities, thus terminating their contemplation 

 prematurely. Nor are these powers (or the like) to be in 

 vestigated only among the medicines for the human body, 

 but also in all changes of other natural bodies. 



A greater evil arises from the contemplation and inves 

 tigation rather of the stationary principles of things from 

 which, than of the active by which things themselves are 

 created. For the former only serve for discussion, the lat 

 ter for practice. Nor is any value to be set on those com 

 mon differences of motion which are observed in the received 

 system of natural philosophy, as generation, corruption, aug 

 mentation, diminution, alteration, and translation. For this 

 is their meaning: if a body, unchanged in other respects, is 

 moved from its place, this is translation; -if the place and 

 species be given, but the quantity changed, it is alteration; 

 but if, from such a change, the mass and quantity of the 

 body do not continue the same, this is the motion of aug 

 mentation and diminution; if the change be continued so as 

 to vary the species and substance, and transfuse them to 

 others, this is generation and corruption. All this is merely 

 popular, and by no means penetrates into nature; and these 

 are but the measures and bounds of motion, and not differ 

 ent species of it; they merely suggest how far, and not how 

 or whence. For they exhibit neither the affections of bodies 

 nor the process of their parts, but merely establish a divi 

 sion of that motion, which coarsely exhibits to the senses 

 matter in its varied form. Even when they wish to point 

 out something relative to the causes of motion, and to estab 

 lish a division of them, they most absurdly introduce nat 

 ural and violent motion, which is also a popular notion, 



