Though many of these opinions differ in some measure, they all agree to prove how precious this humor was held. It has been a question whether it has any analogy to any other humor? Or is it the same with that liquid, which, under the name of the animal spirits, conveyed by the nerves, concurs to all the functions of the animal machine that are of any, though ever so little importance, and of which the depravation produces such an infinity of evils, so frequent and so unaccountable? To answer this question positively, it would be requisite first to know intimately the nature of these two humors; and we are very far from having as yet reached that degree of knowledge: we can at best propose nothing more than ingenious and probable conjectures. HOFFMAN says, “It is easy enough to conceive how there is such a close alliance between the brain and the testicles, since both those organs separate from the blood the most subtile and the most exquisite lymph, destined to give force and motion to the parts, and even to have an influence on the functions of the soul. So that it is not possible but that an over-abundant dissipation of these liquids should destroy the strength of the mind and body[57].” Elsewhere he says, “That the seminal liquid is like the animal spirits, which are separated from the brain, distributed through all the nerves of the body, and seems to be of the same nature; whence it comes, that the more of it is dissipated, the less there is secreted of the animal spirits.” M. DE GORTER is in the same idea. “The seed (says he) is the most perfect, the most importantly essential of all the animal liquids: it is also the most elaborate; it is the result of all the digestions; its intimate connection with the animal spirits, proves that, like them, it draws its origin from the most perfect humors[58].” In short, it appears by these testimonies, and by a croud of others which it would be superfluous to quote, that it is a liquid of the utmost importance; that it might be called the _essential oil_ of the animal liquids; or, perhaps more correctly, the _spiritus rector_, the dissipation of which leaves the other humors weak, and, in some measure, dead or vapid. But whatever may be the original importance of this humor, it may be objected, that since it is separated from the others, and deposited in its appropriate reservoirs, of what use can it be to the body after this its separation? It is granted, they will say, that an over-abundant evacuation of those humors, which are in actual circulation through the vessels, and by that very circulation contribute to nutrition, such as the blood, the serosity, the lymph, &c. may weaken; but it is not so easy to conceive how a humor, that is no longer in circulation, that is, in a state of separation, can produce this effect.