It may be the privilege of a few to live until ninety, even though worshipping immoderately at the altars of Bacchus or Venus! But these are very few, and as we have seen, they have lived on the heritage of their forefathers, not merely in an illustrative sense, but also in reality, for the greater number of such persons have grown up in easy circumstances without knowing the wear and tear of care and sorrow. Not only old age, but the majority of diseases, are due to our own fault in undermining our natural immunity against infections, and subjecting our various organs to unreasonable overwork and exertion. We do not believe that the worst slave-driver of olden days subjected his slaves to such treatment as we do our own organs, and especially our nerves. At last they must rebel, and disease, with early death or premature old age, will be the result. It is literally true, as the German proverb says: “Jeder ist seines Glückes Schmied” (every man is the locksmith of his own happiness), and as a variation on this we would say: “Every man is the guardian of his own health.” ------------------------------------------------------------------------ CHAPTER IX. THE RATIONAL PREVENTION OF PREMATURE OLD AGE AND THE TREATMENT OF OLD AGE. _General Remarks._ WE have shown in previous chapters, through facts from pathological anatomy, experimental pathology, and clinical medicine, that old age is a disease characterized by the abundant growth of connective tissue, diminution of the oxidations, and a condition of auto-intoxication. This disease is caused by the degeneration of the glands with internal secretion, especially the thyroid, ovaries, testicles, liver, and kidneys. In the same way, and to the same extent as most other diseases, this disease is also amenable to treatment, although a thorough cure, except in cases beginning in very early years, is just as little possible as in most other diseases. In keeping with the majority of diseases, old age is progressive, and, in fact, is so to a far higher degree than other diseases. It is seldom stationary; it goes on all the time. This we shall easily be brought to understand from the fact that the more time progresses, the more food is taken to sustain the processes of life. By the deficient action of the glands, whose rôle is the proper assimilation of the food and the destruction and elimination of poisonous products of the body, these toxic substances will accumulate, day by day, especially if meat be taken, and thus the continual poisoning will be augmented as time goes on. Thus it must be our most important task to check the progress of a condition in so high a degree injurious to the body. Let us consider the means by which we can prevent this disease, for “prevention is better than cure,” says the English proverb.