——_Gigni pariter cum corpore, et una_ _Crescere sentimus, pariterq; senescere mentem._ _Nam velut infirmo pueri teneroque vagantur_ _Corpore; sic animi sequitur sententia tenuis:_ _Inde ubi robustis adolevit viribus ætas,_ _Consilium quoque majus, et auctior est animi vis:_ _Post ubi jam validis quassatu’st viribus ævi_ _Corpus; et obtusis ceciderunt viribus artus._ _Claudicat ingenium, delirat linguaque, mensque:_ _Omnia deficiunt, atque uno tempore desunt;_ _Quin etiam morbis in corporis avius errat_ _Sæpe animus, dementit enim, deliraque fatur._[82] Observation also teaches us, that of all the diseases there is not one that affects more quickly the soul, than those of the nervous system: of this the epileptics, who, at the end of a certain number of years, most commonly fall into a state of imbecillity, furnish a melancholy proof, which may, at the same time, give us to understand, that it is not at all surprising that those acts, which, as has been precedently remarked, are always in a small degree epileptic, should produce such a weakening of the brain, and, consequentially, of the vital faculties. The weakening of the brain, and of the nervous system, is followed by that of the senses, which is nothing but natural. SANCTORIUS, HOFFMAN, and some others, have endeavoured at explaining why the sight more especially suffers; but their reasons, however founded on truth, do not appear to me sufficient. The principal ones, and which are drawn from qualities particular to this organ, are, the multitude of parts that constitute the eye, and which being, all of them, susceptible of different ailments, render it infinitely more subject than the others, to disorders. In the next place the nerves serve here for various uses, and are very numerous. In short, the afflux of humors to that part, during the time of the act, an afflux of which the sparkling perceived in the eyes of animals, at that juncture, forms a sensible proof, produces in the vessels of the eye, at first a weakness, and afterwards obstructions, of which a loss of sight is the necessary consequence. Nor is it actually difficult to answer the question above proposed, why it is that Eunuchs, who have no seed, are not exposed to the disorders we have precedently described? Of this there are two very sufficient reasons.