From the principle of the identity of nature it follows that bodies which are remote from us are the same in kind with those that are with us and near us; nothing may be denied of the former which is affirmed of the latter, and _vice versa_. There can be no doubt, therefore, of their similar composition and similar parts. Thus if here on the earth we nowhere see fire subsisting without earth, nowhere earth without water or fire, while their composites are both contained in and penetrated by air and void, then the same is necessarily the case in the upper world also; neither sense nor reason compels us to assert or suspect otherwise.[369] Bruno has grasped, however confusedly, the idea that each individual, each being in the universe, is as it were an epitome of the universe itself; that each therefore stands in a peculiar relation to it, differing from it only in the "proportion" in which the elements are composed into unity. It is impossible not to see in this idea the germ of the most important development of Leibniz' philosophy, whatever the source may have been through which it came to the latter. It is true that here, at least, Bruno's conception appears much less spiritual than that of his successor, inasmuch as he is thinking rather of the actual physical elements which go to make up a body (and in which all bodies are similar to one another). On the other hand, the formation of the body is, in his view, the work of the soul, and it is in the last resort the identity of the universal soul of nature in all its members that brings each of these into correspondence with all others. It is true, also, that Bruno has no definite explanation of what constitutes an individual, and his readers are exposed to the dilemma either of regarding the physical atoms as themselves "_beseelt_,"--a view which Bruno nowhere sanctions,--or, on the other hand, of accepting a dualism of spirit (the soul of the universe or God) and matter (the material atoms, moisture, fire, and ether). Yet the tenour of Bruno's philosophy is wholly opposed to such a dualism. As a corollary of this theory, Bruno suggested an explanation of what has been called "spontaneous generation," supported, however, by tales of the credulous rather than by actual observation. "Dust that has been heated by the sun, as soon as moisture falls upon it, becomes a frog, the whole substance of dung goes into worms or flies, the body of a horse will turn into wasps, the provident bee rises from the body of an ox!"[370] As each thing is in its inner nature identical with every other, so it _may_, and in the natural course _does, become_ every other, as we have learned from the Italian works. Nevertheless, the outward appearances of things do not cease to be different from one another. "That is more latent in one subject which is more unfolded in the remainder." "The subject of all is one (_monas_), and all things are in truth one, although in individuals they seem to be many."