When the hemispheres are removed, the animal instantly loses its perception; it no longer sees nor hears,[100] &c. notwithstanding all the organs of the senses, the eye, the ear, &c. subsist, and the impressions take place. Therefore the principle that perceives is _one_. Lost for one sense, it is lost for all the senses. And if it be _one_ for the external senses, how can it be other than _one_ for the faculties of the soul? Gall therefore cannot suppose the existence of several distinct principles for the faculties of the soul, otherwise than because he supposes several distinct principles for the perceptions; and he only supposes several principles for the perceptions because he confounds impression with perception. The whole of his psycology arises from a mistake; and the whole of his anatomy is constructed for the sake of his psycology. In psycology he endeavours to prove that the faculties of the soul are merely _internal senses_; in anatomy, he endeavours to prove that the organs of the faculties of the soul only repeat and reproduce the organs of the _external senses_. Now an _organ_, that is to say, under the present point of view, the _nerve_ of an _external sense_, is nothing more than a _fascicle_ of _nervous fibres_. Therefore the brain, under the theory, can be nothing but a collection of _fascicles_ of _fibres_.[101] According to Gall, the origin, the development, the structure and mode of termination, as to the organs of the faculties of the soul and the organs of the external senses, every thing is similar, every thing is in common. And yet the primitive difficulty remains unsolved. When I say an _organ of the senses_, I speak of a very determinate nervous apparatus. But is the same thing true when I say an organ of the brain? What is an organ of the brain? Is it a _fascicle_ of _fibres_? Is it each particular fibre? But if it be a _fascicle_ of _fibres_, there are too few of them, for there are not twenty-seven of them; and twenty-seven are necessary, for there are twenty-seven faculties. If it be each particular fibre, then there are too many of them, and far too many, because there are only twenty-seven faculties. What are we to do in this difficulty? We must do as Gall does: sometimes say it is a fascicle of fibres; at other times, that it is each fibre in particular. In one place he says: “The brain consisting of several divisions whose functions are totally different, there are several primary bundles, which contribute by their development to produce it. Among these bundles we place the anterior and posterior pyramids, the bundles that come off direct from the corpora olivaria, and some others that are concealed in the interior of the medulla oblongata.”[102] _And there are yet some others_; be it so; but they never can amount to twenty-seven.