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THE human body is an organised compound substance, but its known elements belong to the inorganic kingdom. All its parts are formed from the blood, and the blood consists of two ingredients-fibrine and serum. Fibrine is identical in its composition with muscular fibre, and serum with white of egg. These two substances contain ten chemical elements: namely, oxygen, hydrogen, nitrogen, carbon, phosphorous, sulphur, chlorine, potash, soda, and lime. Iron and certain fatty substances also are found in the blood.

At present, the primitive organic form is considered to be a cell. The tissues which enter into the structure of complex organs are regarded only as the means for supplying the conditions requisite for the vital operations of the cells. Different cells have different properties; one set of cells, for example, separates certain elements from the blood and forms bones, another set forms nerves. The cause of the formation of the cell, and of different cells possessing different properties, is unknown. Many physiologists name it the vital force, and regard it as the source of growth and reproduction. Several of the conditions under which cells develope themselves into complex organs are known; but it is unascertained whether their evolutions are the result merely of properties possessed by matter in its inorganic form, or of matter and some new force added to it. It has not been proved that inorganic matter can become organised simply by the powers known to be inherent in itself. Organic substances and beings exist, and possess the power of absorbing and converting inorganic matter into organic; but science has not revealed how the first of them became organic, and whence they derived this power of assimilation. Suffice it, therefore, here to observe, that out of inorganic elements, cells and various tissues are formed. These, in the progress of growth, are developed into specific organs, such as the bones, muscles, nerves, lungs, and so forth, each having a peculiar function. The action of the elements

out of which these cells, tissues, and organs are formed is precise and uniform; and the compound organism, called the human body, appears as evidently to be a result of design as a clock, a steam-engine, or any other mechanical production of human skill, only immeasurably transcending, in the offices which it performs, and in the admirable contrivances by which these are accomplished, every combination by mortal skill. The following arguments in favour of a vital principle have frequently been used.

It is said, for example, that, strictly speaking, the elements before named are only the chemical residuum after the vital power has ceased to act; but it does not necessarily follow that these, in the same forms and proportions in which they are found after death, constitute all that enters into the composition of the body while alive. The vital force may be some element still unknown, which combines with them and forms a new compound, but which escaping at death leaves these elements as a mere residuum. Water, the steam of water with its prodigiously expansive power, and ice, are all composed of oxygen and hydrogen; but their characteristics are widely different, according to the amount of heat which they contain; and heat is still an unknown force or action, for it is not now regarded as a substance. In like manner, be the vital principle what it may, we must constantly bear in mind that a living man may consist of substances different from every thing we know chemically, and different from the elements present in his body in a state of death in the actual condition of science, the difficulty of ascertaining what he really is, seems insuperable; for we cannot discover it from consciousness, and chemical analysis of the body is impossible without killing it. Blood, when drawn from the body, dies, and so do all other parts when separated from the living organism.

Another theory of life dispenses altogether with a vital principle as a force distinct from matter. According to it, there is no evidence to prove the existence of any particular vital principle, but life may be referred to a more complicated action of the common properties of matter than we see in inorganic substances. When carbon and oxygen, for instance, are brought together under certain circumstances, carbonic acid is formed. Why this happens, we cannot tell; and we content ourselves with saying, that the union takes place according to chemical laws-in other words, that, in the same circumstances, these substances constantly and unvaryingly combine in the same manner. Certain properties have been bestowed upon carbon and oxygen by the Author of Nature, and these never alter. We can scarcely form a notion of

what they are in themselves. On this point our present chemical knowledge is meagre in the extreme. As already observed, when carbon and oxygen meet under certain circumstances they form carbonic acid, but we understand nothing of various important modifications which ensue by the addition of nitrogen and hydrogen. A grain of wheat is composed of oxygen, hydrogen, nitrogen, carbon, and some alkaline and earthy salts. The different atoms are so constituted, that, in certain circumstances, a disturbance of them takes place-motion ensues, and different additional changes of matter follow, all according to the fixed properties of the different atoms. So long as the grain of wheat remains unaltered, so long as its atoms retain their original position and their original powers of action upon each other, it retains the capability of being called into life; that is, of passing through a series of changes totally independent of any volition on its part, but which ensue according to laws analogous to those which guide the motions of a watch, only much more complicated in their nature. The great problem would be to arrange the atoms of matter in such a way, that, in certain circumstances, wheat, or oats, or barley, should be the produce of the atomic changes in the elements which are common to all of these substances. This seems to have been done by the great Intelligent Cause at the commencement of nature; and laws of reproduction being established, the organised kingdom seems to proceed without any more direct supervision than is bestowed upon the inorganic world. Indeed, many authorities now maintain that both are subject to similar laws. This is a startling view when we compare man with a stone; but it is less so when we pass from a stone to a shell, from a shell to a piece of wood, from that to a sponge, from a sponge to blubber, and so on up to man. The extinction of life seems to be nothing more or less than a disturbance of the movement of the atoms, similar to that which occurs when we blow out a candle. The properties of the atoms of the candle remain the same, but the circumstances in which they are placed are different, and the phenomena which accompany their future motions, if heat be not reapplied so as to produce ignition, are also different. I need not go farther into the matter. These observations will give the reader a view of the nascent ideas on the subject now entertained in Germany, and I give them only historically as such.

The advocates of this theory ask the question:-If life be due to a vital principle, what becomes of it in frozen fishes, and dried animalculæ, some of which may be retained in a desiccated condition for years? According to the new theory,

the conditions of change were simply removed; restore them, and life, that is, motion of their particles, returns. When a man faints and falls into the water, he is much more likely to be restored to animation, even after a considerable period of immersion, than if he had fallen in while the vital changes were in full activity: The vital functions go on more slowly in a fainting man, than in one in full health and activity; and less oxygen being needed, want of respiration is not so soon fatal. His condition is analogous to that which occurs in hybernating animals, and in men who in India are temporarily buried, and revive.

I have observed that those in whom the organs of Wonder, Imitation, and Ideality, are large, are predisposed to regard life as a distinct force superadded to matter; while those in whom these organs are moderately developed, and in whom Causality and Comparison are large, are inclined to prefer the latter theory, or some one analogous to it. They ascribe to matter, when placed in certain circumstances, the power of assuming organic forms and maintaining organic action, as one of its own attributes.* By such of them as are Theists, however, this power is regarded as derived from the Deity. As before remarked, there is no satisfactory evidence to show that inorganic matter can organise itself.

Many divines, as well as philosophers, have held the opinion that man has no spiritual substance or soul distinct from the body, but becomes extinct at death, and so continues till the resurrection. Among these are Milton,† Locke, Bishops Sherlock § and Law,|| Dr John Taylor,¶ Dr Priestley,** Robert Hall,tt and Archdeacon Blackburne ;‡‡ to whom may be added Bishop Watson, although, being naturally averse to dogmatism on subjects so abstruse, he went no farther than to say that he thought the point doubtful-declaring that he was "not disturbed at his inability clearly to convince himself that the soul is or is not a substance distinct from the body;"§§ that

See an Inquiry into the Opinions, Ancient and Modern, concerning Life and Organization. By John Barclay, M.D. Edinburgh, Bell and Bradfute, 1822. †Treatise on Christian Doctrine, vol. i., p. 250.

The Reasonableness of Christianity as delivered in the Scriptures; at the beginning.

§ Discourses vi. and xlix.; Sherlock's Works, ed. 1830, vol. i., p. 124, and vol. ii., p. 431.

Considerations on the Theory of Religion, 5th ed., pp. 49, 186; and more particularly, Discourse appended to it (pp. 343-429) on the Nature and End of Death under the Christian Covenant.

Letter to Bishop Law, quoted by the latter, p. 422.

**Disquisitions relating to Matter and Spirit. Lond. 1777.

tt Letter to his Congregation at Bristol in 1790, quoted in the Encyc. Brit., 7th ed., vol. xi., p. 115.

Blackburne's Works, vols. ii. and iii.

$$ Anecdotes of his own Life, 2d ed., vol. i., p. 24.

"he despaired of ever seeing the question clearly decided, whether the brain is the efficient or the instrumental cause of sensation ;"* and that "if the Gospel is not true, he could have no expectation of a future state."

The discovery of the cause of life or the nature of the vital principle may be practically important; because if man could find it out and ascertain the conditions under which it acts, he might acquire the power of influencing the formation of organisms at their source, and hence might modify the whole series of their actions. Theologically considered, however, this discovery appears to be unimportant; because if we admit the existence of God, and believe that in calling man into existence He had a purpose, we cannot conceive that He should have chosen a wrong substance out of which to fashion him. We may rest assured that the object of man's existence, be it what it may, will be accomplished, of whatever essence his organism consists.

I may add, that the opinion is now very general among thinking men, that the question of immortality has no dependence on that of the immateriality of the soul and possibility of its separate existence, but that, whatever the nature of the soul is, it can be immortal or mortal only by the will of God.‡

Some of the advocates of a superadded vital principle entertain the notion that it is spiritual or immaterial, and that it acts even in the present life independently of matter. This, however, appears to me to be an error. Even assuming the existence of a separate and superadded vital principle, it does not follow that the body, compounded of it and matter, possesses the attributes generally ascribed to an immaterial being or soul; or that the vital principle, while forming a part of the living organism, is emancipated from the laws and control of matter. A more reasonable proposition would be, that the unknown principle, when combined with diversities of organic structure, would produce diversities of living powers. Combined with the organism of vision, for example, we may suppose that it would produce vision: but vision is not emancipated by it from the influence of matter; on the contrary, this sense is affected by every cause that changes the condition of the structure, and is exercised according to fixed laws, which are embodied in the science of optics. The same remarks apply to the organs of hearing, touch, taste, and smell. And not only so, but the vital principle, combined with one portion of * Anecdotes of his own life, 2d ed., vol. ii., p. 400. † Ib., vol. i., p. 395.

This opinion is expressed by Dr John Taylor in a passage quoted by Bishop Law, p. 423; by Dugald Stewart, Prelim. Disert. to Encyc. Brit., p. 58; and by sundry other writers mentioned in the Phren. Jour. xv. 348. See Locke's opinion on the subject in detail, Phren. Jour. xvi. 60; and Baron Smith's, xvi. 287.

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