In their wild state, monkeys, like ourselves, are subject in their old age to various distressing ailments. Senile degeneration, then, which is universally looked upon as one of the greatest evils of life, is by no means restricted to the human race. Old age, as portrayed in the Buddhist legend, referred to in chap. vi., is perhaps somewhat exaggerated, but this period of life is undoubtedly characterised by changes of such a nature as considerably to affect the happiness of the old. Buddha, being a pessimist, took too dark a view of this, but let us hear what optimists have to say on the subject. Max Nordau, a doctor, a writer of books and a journalist, says: “Physically speaking, an old man presents an unpleasant picture of decrepitude to the casual observer. Morally speaking, he is a blind and pitiless egotist, having lost all interest in anything outside himself. Intellectually he becomes feeble-minded and narrow in his views, being governed by antiquated notions and prejudices, and incapable of grasping new ideas.”[291] It may be objected that I am here supporting my argument by quoting from a writer who, in his capacity of clever journalist, rather forces the note. Let me therefore refer to what a learned physiologist said when addressing a serious audience assembled for the purpose of obtaining truth and information from his lips. After dealing in broad outline with the physical degeneracy caused by old age, Longet[292] draws the following mental picture: “The old feel that their task in life is accomplished, and believe themselves to be universally grudged the space they occupy in the world. This renders them suspicious of all around them, and jealous of the young. Their craving for solitude and the uncertainty of their tempers are due to the same cause. All old people are not like this, of course. The hearts of some remain youthful and beat strongly within their feeble frames, but, as a general rule, they are morose and a nuisance to themselves and others, excepting when they are surrounded by their children or grandchildren, who like to listen to them about the past, and who make excuses for the present. Thus the years speed onward, every round of the clock bringing the end nearer, and every hour adding a new wrinkle to their faces, some fresh weakness and some new regret. Their bodies ... become decrepit; their backbones, too weak to hold them upright, curve over and bend them downwards towards the earth.” There can be no doubt but that the period of old age is sad, and a thorough knowledge of it is necessary before it can be understood. Disease can only be successfully dealt with when the cause of its presence is known, and so it is with old age. Is it possible, one might ask, at the present stage of the world’s knowledge, to define, with even approximate accuracy, the characteristic features of senile decay? The task is difficult, for although the subject is very important, few facts have been collected.