the beginning of summer and winch inhabit deep and still waters, as the carp, bream, pike, tench, &c., deposit their eggs upon aquatic vegetables, which by the influence of the solar light constantly preserve the water in a state of aëration. The trout, salmon, hucho, and others of the Salmo genus, which spawn in the beginning or end of winter, and which inhabit rivers fed by cold and rapid streams which descend from the mountains, deposit their eggs in shallows on heaps of gravel, as near as possible to the source of the stream where the water is fully combined with air; and to accomplish this purpose they travel for hundreds of miles against the current, and leap over cataracts and dams: thus the Salmo salar ascends by the Rhone and the Aar to the glaciers of Switzerland, the hucho by the Danube, the Isar, and the Save, passing through the lakes of the Tyrol and Styria to the highest torrents of the Noric and Julian Alps.
Phil.—My own experience proves in the strongest manner the immediate connection of sensibility with respiration; all that I can remember in my accident was a certain violent and painful sensation of oppression in the chest, which must have been immediately succeeded by loss of sense.
Eub.—I have no doubt that all your suffering was over at the moment you describe; as far as sensibility is concerned, you were inanimate when your friend raised you from the bottom. This distinct connection of sensibility with the absorption of air by the blood is, I think, in favour of the idea advanced by our friend, that some subtle and ethereal matter is supplied to the system in the elastic air which may be the cause of vitality.
The Unknown.—Softly, if you please; I must not allow you to mistake my view. I think it probable that some subtle matter is derived from the atmosphere connected with the functions of life; but nothing can be more remote from my opinion than to suppose it the cause of vitality.
Phil.—This might have been fully inferred from the whole tenor of your conversation, and particularly from that expression, “that which commands sensation will not be their subject.” I think I shall not mistake your views when I say that you do not consider vitality dependent upon any material cause or principle.
The Unknown.—You do not. We are entirely ignorant on this subject, and I confess in the utmost humility my ignorance. I know there have been distinguished physiologists who have imagined that by organisation powers not naturally possessed by matter were developed, and that sensibility was a property belonging to some unknown combination of unknown ethereal elements. But such notions appear to me unphilosophical, and the mere substitution of unknown words for unknown things. I can never believe that any division, or refinement, or subtilisation, or juxtaposition, or arrangement of the particles of matter, can give to them sensibility; or that intelligence can result from combinations of insensate and brute atoms. I can as easily imagine that the planets are moving by their will or design round the sun, or that a cannon ball is reasoning in making its parabolic curve. The materialists have quoted a passage of Locke in favour of their doctrine, who seemed to doubt “whether it might not have pleased God to bestow a power of thinking on matter.” But with the highest veneration for this
great reasoner, the founder of modern philosophical logic, I think there is little of his usual strength of mind in this doubt. It appears to me that he might as well have asked whether it might not have pleased God to make a house its own tenant.
Eub.—I am not a professed materialist; but I think you treat rather too lightly the modest doubts of Locke on this subject. And without considering me as a partisan, you will, I hope, allow me to state some of the reasons which I have heard good physiologists advance in favour of that opinion to which you are so hostile. In the first accretion of the parts of animated beings they appear almost like the crystallised matter, with the simplest kind of life, scarcely sensitive. The gradual operations by which they acquire new organs and new powers, corresponding to these organs, till they arrive at full maturity, forcibly strikes the mind with the idea that the powers of life reside in the arrangement by which the organs are produced. Then, as there is a gradual increase of power corresponding to the increase of perfection of the organisation, so there is a gradual diminution of it connected with the decay of the body. As the imbecility of infancy corresponds to the weakness of organisation, so the energy of youth and the power of manhood are marked by its strength; and the feebleness and dotage of old age are in the direct ratio of the decline of the perfection of the organisation, and the mental powers in extreme old age seem destroyed at the same time with the corporeal ones, till the ultimate dissolution of the frame, when the elements are again restored to that dead nature from which they were originally derived. Then, there was a period when the greatest philosopher,
statesman, or hero, that ever existed was a mere living atom, an organised form with the sole power of perception; and the combinations that a Newton formed before birth or immediately after cannot be imagined to have possessed the slightest intellectual character. If a peculiar principle be supposed necessary to intelligence, it must exist throughout animated nature. The elephant approaches nearer to man in intellectual power than the oyster does to the elephant; and a link of sensitive nature may be traced from the polypus to the philosopher. Now, in the polypus the sentient principle is divisible, and from one polypus or one earthworm may be formed two or three, all of which become perfect animals, and have perception and volition; therefore, at least, the sentient principle has this property in common with matter, that it is divisible. Then to these difficulties add the dependence of all the higher faculties of the mind upon the state of the brain; remember that not only all the intellectual powers, but even sensibility is destroyed by the pressure of a little blood upon the cerebellum, and the difficulties increase. Call to mind likewise the suspension of animation in cases similar to that of our friend, when there are no signs of life and when animation returns only with the return of organic action. Surely in all these instances everything which you consider as belonging to spirit appears in intimate dependence upon the arrangements and properties of matter.
The Unknown.—The arguments you have used are those which are generally employed by physiologists. They have weight in appearance, but not in reality. They prove that a certain perfection of the machinery of the body is essential to the exercise of the powers of