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CHAP IV.

OF THE BRAIN, AS A RECEPTACLE OF DISTINCT

ORGANS.

IT

T has already been said, that each circumvolution of nerve in the cerebrum, is to be considered as the nerve or organ of some certain operation of mind : That hence, each internal operation, as well as each external sense, has its own peculiar nerve and organ; and that hence, the brain is not one organ of the soul, not a common organ for all the functions of the mind, but a receptacle for distinct organs.

Tho' this assertion is far from being new, for we find it in Boerhave, Haller, Von Swieten, Schellhammer, Glaser, Jucobi, Sömmering, Tiedemann and Prochaska ; and the academy of Dijon has even made the seat of these organs the subject of a prize dissertation; still it is necessary to state the proof of

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this plurality of organs, which lies in the following observations and reasonings.

1.) Gall first urges, the sense of fatigue arising from the mind being long employed on one subject of contemplation; and the relief and delight we experience in variety. This is analogous to bodily fatigue, which arises, not so much from a general exhaustion of muscular strength, as from the partial use and pressure of the distinct muscles of the body. When we have been long sitting we are relieved by standing; and the bed-ridden find ease by à change of posture.

That mental exercise is analogous to that of the body, as well in general, as in respect to the different kinds of employment, is very strikingly apparent. Every man, who is habituated to a life of study, knows, that after having spent hours in reflecting upon an abstract idea, or in labouring to analyse an ins tricately compounded problem of science; when he feels exhausted by the intenseness of his study, if he take up a work of fancy or taste, (nor do I mean here the idly taking up a book that neither requires nor allows of attention, but a work demanding, in the perusal, no less energy of mind, tho’ of a different kind, than a scientific disquisition) he will find himself as fresh to the task, his comprehension as lively, his attention as ready, as if just arisen from the healthiest and most invigorating sleep. It has been said of some hard students, that they knew no rest but in the change of object; and we see that children never tire in their sports; partly (no doubt) because they are restrained by no laws of decorum from indulging in the utmost variety of posture and motion; they bring every muscle of their bodies into play; the vigour of their youthful frame soon exhausts each particular organ, but instinct leads them unconsciously to the easy relief; hence the restless impatience, and ever changing pursuits of childhood, equally apparent in the exercises of both body and mind. Let it not be said here, that this diversity of organs, which is supposed to exist in the brain, destroys the unity of the mind itself, for this argument is destroyed by the analogy here pointed out. It is one will which sets every muscle in motion, as well as One mind which acts in

every operation of intellect: In both cases the mode of action is alike incomprehensible, and yet, where we have similar phænomena, it is but reasonable to suppose that the modes and principle of action are also similar. The complete analogy between the affections of body and those of the mind, compels us in

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and insanity very frequently assumes the shape of a partial disease. Instances will be given hereafter.

The notion thus supported explains many of the common phænomena of life, viz.

a.) Watchfulness, which is that state in which all the organs of animal life are at the command of our will.

b.) Sleep, (that is, healthy and sound sleep) which is that state when all the organs of animal life are at rest, (the organs of organic life are distinguished by never tiring.)

c.) Dreaming, which takes place when some one or more of the organs of animal life are in a state of activity, while the others are at rest.

The activity of these organs awakens the consciousness of the others, Consciousness appertains to all

organs, and has none of its own : Hence there is no dream without consciousness, however we may forget our dreams. During disease, there may be dreaming without sleep, owing to the disordered activity of certain organs, of this kind is delirium. : In a state of somnambulism the whole vital energy: is concentred in certain organs, while the others entirely rest. And in the same way are we to account for the high concentration of power, the heightened sensibility, and the sudden bursts of

intellect,

intellect, and the extasies of a disordered frame.

d.) Lastly, confirmed madness, or that disorder which consists in certain false notions and conceptions of things, which lies in the power of volition being lost over certain organs of intellectual life; and this arises from those organs (it matters not how) being in an highly excited or irritated state.

Such are the arguments a priori in favor of distinct organs

in the brain; they can be confirmed only by those distinct organs, or at least their site, being pointed out in fact. And in this lies the science, which Dr. Gall professes to have first discovered and made known to the world. I have used the term science here, not in its proper sense, but vaguely as we use it to express any knowledge, or any probable opinion founded on observation. The physiologist knows very, well on what evidence his theories rest, as to the more obvious and palpable functions of animal life, and will, in respect to Dr. Gall's speculation, be content with proof as strong as the nature of the case admits, even should it fall short of the evidence which some des partments of his science afford. He will not

organs

should be laid before the eye, in like manner as the muscles of E

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expect that the

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