Part IV — Should We Try to Prolong Human Life?
I The Benefit to Humanity
Complaints of the shortness of our life—Theory of “medical selection” as a cause of degeneration of the race—Utility of prolonging human life
Although the duration of the life of man is one of the longest amongst mammals, men find it too short. From the remotest times the shortness of life has been complained of, and there have been many attempts to prolong it. Man has not been satisfied with a duration of life notably greater than that of his nearest relatives, and has wished to live at least as long as reptiles.
In antiquity, Hippocrates and Aristotle thought that human life was too short, and Theophrastus, although he died at an advanced age (he lived probably seventy-five years) lamented when he was dying “that nature had given to deer and to crows a life so long and so useless, and to man only one that was often very short.”105
Seneca (De brevitate vitæ) and later, in the 18th century, Haller, strove in vain against such complaints, which have lasted until our own days. Whilst animals have no more than an instinctive fear of danger, and cling to life without knowing what death is, men have acquired an exact idea of death, and their knowledge increases their desire to live.
Ought we to listen to the cry of humanity that life is too short and that it would be well to prolong it? Would it really be for the good of the human race to extend the duration of the life of man beyond its present limits? Already it is complained that the burden of supporting old people is too heavy, and statesmen are perturbed by the enormous expense which will be entailed by State support of the aged. In France, in a population of about 38 millions, there are two millions (1,912,153) who have reached the age of 70, that is to say, about five per cent. of the total. The support of these old people absorbs a sum of nearly £6,000,000 per annum.106 However generous may be the views of the members of the French Parliament, many of them hesitate at the idea of so great a burden. Without doubt, men say, the cost of maintaining the aged will become still heavier if the duration of life is to be prolonged. If old people are to live longer, the resources of the young will be reduced.
If the question were merely one of prolonging the life of old people without modifying old age itself, such considerations would be justified. It must be understood, however, that the prolongation of life would be associated with the preservation of intelligence and of the power to work. In the earlier parts of this book I have given many examples which show the possibility of useful work being done by persons of advanced years. When we have reduced or abolished such causes of precocious senility as intemperance and disease, it will no longer be necessary to give pensions at the age of sixty or seventy years. The cost of supporting the old, instead of increasing, will diminish progressively.
If attainment of the normal duration of life, which is much greater than the average life to-day, were to overpopulate the earth, a very remote possibility, this could be remedied by lowering the birth-rate. Even at the present time, while the earth is far from being too quickly peopled, artificial limitation of the birth-rate takes place perhaps to an unnecessary extent.
It has long been a charge against medicine and hygiene that they tend to weaken the human race. By scientific means unhealthy people, or those with inherited blemishes, have been preserved so that they can give birth to weak offspring. If natural selection were allowed free play, such individuals would perish and make room for others, stronger and better able to live. Haeckel has given the name “medical selection” to this process under which humanity degenerates because of the influence of medical science.
It is clear that a valuable existence of great service to humanity is compatible with a feeble constitution and precarious health. Amongst tuberculous people, those with inherited or acquired syphilis, and those with a constitution unbalanced in other ways, that is to say, amongst so-called degenerates, there have been individuals who have had a large share in the advance of the human race. I need only instance the names of Fresnel, Leopardi, Weber, Schumann and Chopin. It does not follow that we ought to cherish diseases and leave to natural selection the duty of preserving the individuals which can resist them. On the other hand, it is indispensable to try to blot out the diseases themselves, and, in particular, the evils of old age, by the methods of hygiene and therapeutics. The theory of medical selection must be given up as contrary to the good of the human race. We must use all our endeavours to allow men to complete their normal course of life, and to make it possible for old men to play their parts as advisers and judges, endowed with their long experience of life.
To the question propounded at the beginning of this section of my book, I can make only one answer: Yes, it is useful to prolong human life.