NATURE OF THINGS. 451 



this example, not in their investigation of causes to catch 

 at only one element, and so too lightly to pronounce upon 

 them; but to look around them with caution, and rivet 

 their contemplation more intensely and profoundly. 



Of the Dissimilarity of things celestial and sublunary, in 

 regard to eternity and mutability, that it has not been 

 proved to be true. 



x. 



The received opinion that the universe is regularly divided 

 and discriminated by spheres as it were, and that there is 

 one system of heavenly and another of sublunary being, 

 appears to have been adopted, not without rational grounds, 

 provided the opinion is applied with proper modifications. 

 For there is no doubt that the regions situated beneath the 

 lunar orb, and above it, differ in many and important respects. 

 Yet is not that belief more certain than this other, that the 

 bodies in both spheres have tendencies, appetencies, and 

 motions which are common to both. We ought then to 

 imitate the unity of nature, to discriminate those spheres 

 rather than rend them asunder, and not to break down 

 the continuity of our contemplation. But with respect to 

 another received opinion, that the heavenly bodies undergo 

 no change, but that the terrestrial or elementary (as they 

 are called) are subject to change; and that the matter of 

 the last resembles a courtezan ever seeking the embrace- 

 ment of new bodies, but of the other a matron linked to 

 one in stable and inviolable union ; it seems but a popular 

 notion, weak, and originating in appearances and super 

 stition. This notion appears to be tottering, and without 

 foundation, when viewed in either way. For neither does 

 their imagined eternity consist with heaven, nor their muta 

 bility with earth. For with respect to heaven, we cannot 

 rest upon it as a reason for changes not happening there, 

 that they do not emerge to our view, the view of man being 

 prevented no less by distance of place than by tenuity of 

 bodies. For various changes are found to take place in 

 the air, as is evident in heat, cold, smells, sounds, which do 

 not fall within the line of sight. Nor again, I suppose, 

 would the eye, if placed in the orb of the moon, descry 

 across such a prodigious interval, what operations, move 

 ments, and changes presented themselves on the face of 

 the globe, in engines, plants, animals, and so on, which 

 on account of their distance would not equal the bulk of 



