2213. For it is known that the interiors of an animal are entirely different from the externals: from the externals no one can conclude that the interiors are of such a quality, unless they should have been revealed through optical sight; and then it appears that they are wholly dissimilar, consisting indeed of cerebra, spinal medulla, lungs, heart, or little hearts, stomach, liver, vessels devoted to generation, and of other things, like as in the great animal, moreover of innumerable fibers, vessels, tunics, ligaments, in order that they may operate with unanimity. Thus they constitute a body, which is only the complex of all, and appears under a simple form to the eye, which is ignorant that it has such and so many components, yea, such components, that should one be wanting it would be imperfect [mancum], and great defects would abound in the compound.