BOOK VIII
OF PROPERTY

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CHAPTER IX
APPENDIX

OF HEALTH, AND THE PROLONGATION OF HUMAN LIFE

Omnipotence of mind. -- Application of this principle to the animal frame. -- Causes of decrepitude. -- Theory of voluntary and involuntary action. -- Present utility of these reasoning. -- Recapitulation. -- Application to the future state of society.

The question respecting population is, in some degree, connected, with the subject of health and longevity. It may therefore be allowed us, to make use of this occasion, for indulging in certain speculations upon this article. What follows, must be considered, as eminently a deviation into the land of conjecture. If it be false, it leaves the system to which it is appended, in all sound reason, as impregnable as ever.

Let us then, in this place, return to the sublime conjecture of Franklin, a man habitually conversant with the system of the external universe, and by no means propense to extravagant speculations, that "mind will one day become omnipotent over matter¹." The sense which he annexed to this expression, seems to have related to the improvements of human invention, in relation to machines and the compendium of labor. But, if the power of intellect can be established over all other matter, are we not inevitably led to ask, why not over the matter of our own bodies? If over matter at however great a distance, why not over matter which, ignorant as we may be of the tie that connects it with the thinking principle, we seem always to carry about with us, and which is our medium of communication with the external universe?

The different cases in which thought modifies the structure and members of the human body, are obvious to all. First, they are modified by our voluntary thoughts or design. We desire to stretch out our hand, and it is stretched out. We perform a thousand operations of the same species every day, and their familiarity annihilates the wonder. They are not in themselves less wonderful, than any of those modifications we are least accustomed to conceive. Secondly, mind modifies body involutarily. To omit, for the present, what has been offered upon this sysbject by way of hypothesis and inference², there are many instances in which this fact presents itself in the most unequivocal manner. Has not a sudden piece of good news been frequently found to dissipate a corporal indisposition? Is it not still more usual for mental impressions to produce indisposition, and even what is called a broken heart? And shall we believe that that which is so powerful in mischief, can be altogether impotent for happiness? How common is the remark, that those accidents, which are to the indolent a source of disease, are forgotten and extirpated in the busy and active? I walk twenty miles in an indolent and half determined temper, and am extremely fatigued. I walk twenty miles, full of ardor, and with a motive that engrosses my soul, and I arrive as fresh and alert as when I began my journey. Emotion, excited by some unexpected word, by a letter that is delivered to us, occasions the most extraordinary revolutions in our frame, accelerates the circulation, causes the heart to palpitate, the tongue to refuse its office, and has been known to occasion death by extreme anguish or extreme joy. There is nothing of which the physician is more frequently aware, than of the power of the mind in assisting or retarding convalesence.

Why is it that a mature man loses that elasticity of limb, which characterizes the heedless gaiety of youth? The origin of this appears to be, that he desists from youthful habits. He assumes an air of dignity, incompatible with the lightness of childish sallies. He is visited and vexed with the cares that rise out of our mistaken institutions, and his heart is no longer satisfied and gay. His limbs become stiff, unwieldy and aukward. This is the forerunner of old age and of death.

A habit peculiarly fabourable to corporeal vigor, is cheerfulness. Every time that our mind becomes morbid, vacant and melancholy, our external frame falls into disorder. Listlessness of thought is the brother of death. But cheerfulness gives new elasticity to our limbs, and circulation to our juices. Nothing can long be stagnant in the frame of him, whose heart is tranquil, and his imagination active.

A further requisite in the case of which we treat, is clear and distinct apprehension. Disease seems perhaps in all instances to be the concomitant of confusion. When reason resigns the helm, and our ideas fluctuate without order or direction, we sleep. Delirium and insanity are of the same nature. Fainting appears principally to consist in a relaxation of intelllect, so that the ideas seem to mix in painful disorder, and nothing is distinquished. He that continues to act, or is led to a renewal of action with prespicuity and decision, is almost inevitably a man in health.

The surest source of cheerfulness is benevolence. To a youthful mind, while every thing strikes with its novelty, the individual situation must be peculiarly unfortunate, if gaiety of thought be not produced, or, when interrupted, do not speedily return with its healing virtue. But novelty is a fading charm, and perpetually decreases. Hence the approach of inanity and listlessness. After we have made a certain round, life delights no more. A deathlike apathy invades us. Thus the aged are generally cold and indifferent; nothing interests their attention, or rouses their sluggishness. How should it be otherwise? The objects of human pursuit are commonly frigid and contemptible, and the mistake comes at last to be detected. But virtue is a charm that never fades. The mind that overflows with kindness and sympathy, will always be cheerful. The man who is perpetually busied in contemplations of public good, can scarcely be inactive. Add to this, that a benevolent temper is peculiarly irreconcilable with those sentiments of anxiety, discontent, rage, revenge and despair, which so powerfully corrode the frame, and hourly consign their miserable victims to an untimely grave.

Thus far we have discoursed of a negative power which, if sufficiently exercised, would, it is to be presumed, eminently tend to the prolongation of human life. But there is a power of another description, which seems entitled to our attention in this respect. We have frequently had occasion to point out the distinction between our voluntary and involuntary motions³. We have seen that they are continually running into each other; our involuntary motions gradually becoming subject to the power of volition, and our voluntary motions degenerating into involuntary. We concluded in an early part of this work⁴, and that, as it should seem, with sufficient reason, that the true perfection of man was to attain, as nearly as possible, to the perfectly voluntary state; that we ought to be, upon all occasions, prepared to render a reason of our actions; and should remove ourselves to the furthest distance, from the state of mere inanimate machines, acted upon by causes of which they have no understanding.

Our involuntary motions are frequently found gradually to become subject to the power of volition. It seems impossible to set limits to this species of metamorphosis. Its reality cannot be questioned, when we consider that every motion of the human frame was originally involuntary⁵. Is it not then highly probable, in the process of human improvement, that we may finally obtain an empire over every articulation of our frame? The circulation of the blood is a motion, in our present state, eminently involuntary. Yet nothing is more obvious than that certain thoughts, and states of the thinking faculty, are calculated to affect this process. Reasons have been adduced which seem to lead to an opinion, that thought and animal motion are, in all cases, to be considered as antecedcent and consequent⁶. We can now perhaps by an effort of the mind correct certain commencing irregularities of the system, and forbid, in circumstances where those phenomena would otherwise appear, the heart to palpitate, and the limbs to tremble. The voluntary power of some men over their animal frame, is found to extend to various articles, in which other men are impotent.

A further probability will be reflected upon these conjectures, if we recollect the picture which was formerly exhibited⁷, of the rapidity of the succession of ideas. If we can have a series of three hundred and twenty ideas in a second of time, why should it be supposed that we may not hereafter arrive at the skill of carrying number of contemporaneous processes without disorder?

Nothing can be more irreconcilable to analogy, than to conclude, because a certain species of power is beyond the train of our present observations, that it is beyond the limits of the human mind⁸. We talk familiarly indeed of the extent of our faculties; and our vanity prompts us to suppose that we have reached the goal of human capacity. But there is little plausibility in so arrogant an assumption. If it could have been told to the savage inhabitants of Europe in the times of Theseus and Achilles that man was capable of predicting eclipses and weighing the air, of reducing to settled rules the phenomena of nature so that no prodigies should remain, and of measuring the distance and size of the heavenly bodies, this would not have appeared to them less incredible than if we had told them of the possibility of maintaining the human body in perpetual youth and vigor. But we have not only this analogy, showing that the discovery in question forms, as it were, a regular branch of the acquisitions that belong to an intellectual nature; but, in addition to this, we seem to have a glimpse of the manner in which the acquisition will be secured.

One remark may be proper in this place. If the remedies here proposed tend to a total extirpation of the infirmities of our nature, then, though we should not be able to promise them an early or complete success, we may probably find them of some utility. They may contribute to prolong our vigor, if not to immortalize it, and, which is of more consequence, to make us live while we live. Every time the mind is invaded with anguish and gloom, the frame becomes disordered. Every time langour and indifference creep upon us, our functions fall into decay. In proportion as we cultivate fortitude and equanimity, our circulations will be cheerful. In proportion as we cultivate a kind and benevolent propensity, we may be secure of finding something to interest and engage us.

Medicine may reasonably be stated to consist of two branches, animal and intellectual. The latter of these has been infinitely too much neglected. It cannot be employed to the purposes of a profession; or, where it has been incidentally so employed, it has been artificially and indirectly, not in an open and avowed manner. "Herein the patient must minister to himself⁹." It would no doubt be of extreme moment to us to be thoroughly acquainted with the power of motives, perseverance, and what is called resolution, in this respect.

The sum of the arguments which have been here offered, amounts to a species of presumption, that the term of human life may be prolonged, and that by the immediate operation of intellect, beyond any limits which we are able to assign. It would be idle to talk of the absolute immortality of man. Eternity and immortality are phrases to which it is impossible for us to annex any distinct ideas, and the more we attempt to explain them, the more we shall find ourselves involved in contradiction.

To apply these remarks to the subject of population. One tendency of a cultivated and virtuous mind is to diminish our eagerness for the gratifications of the senses. They please at present by their novelty, that is, because we know not how to estimate them. They decay in the decline of life, indirectly because the system refuses them, but directly and principally because they no longer excite the ardent of the mind. The gratifications of sense please at present by their imposture. We soon learn to despise the mere animal function, which, apart from the delusions of intellect, would be nearly the same in all cases; and to value it only as it happens to be relieved by personal charms or mental excellence.

The men therefore whom we are supposing to exist, when the earth shall refuse itself to a more extended population, will probably cease to propagate. The whole will be a people of men, and not of children. Generation will not succeed generation, nor truth have, in a certain degree, to recommence her career every thirty years. Other improvements may be expected to keep pace with those of health and longevity. There will be no war, no crimes, no administration of justice, as it is called, and no government. Beside this, there will be neither disease, anguish, melancholy, nor resentment. Every man will seek, with ineffable ardor, the good of all. Mind will be active and eager, yet never disappointed. Men will see the progressive advancement of virtue and good, and feel that, if things occasionally happen contrary to their hopes, the miscarriage itself was a necessary part of that progress. They will know that they are members of the chain, that each has his several utility, and they will not feel indifferent to that utility. They will be eager to inquire into the good that already exists, the means by which it was produced, and the greater good that is yet in store. They will never want motives for exertion; for that benefit which a man thoroughly understands and earnestly loves, he cannot refrain from endeavoring to promote.

Before we dismiss this subject it is proper once again to remind the reader, that the substance of this appendix is given only as matter of probable conjecture, and that the leading argument of this division of the work is altogether independent of its truth or falsehood.

Footnotes

¹Book VIII, Chap. VIII, Appendix, p. 759. The authors who have published their conjectures respecting the possibility of extending the term of human life are many. The most illustrious of these is probably lord Bacon; the most recent is Condorcet, in his Outlines of a History of the Progress of the Human Mind, published the first appearance of this work. These authors however are inclined to rest their hopes rather upon the growing perfection of art, than, as it is here done, upon the immediate and operation of an improved intellect.
²Book IV, Chap. IX.
³Book I, Chap. V; Book IV, Chap. VII, X.