Nations, races, civilisations rise, we shall all agree, because to inherent virtue of breed they add sound customs and laws, acquirements of discipline and knowledge. But, these acquirements made, power established, and crescent from year to year--why do they _then_ fall? If they can _make_ a place for themselves, how much easier should it not be to _maintain_ it? Two explanations, each falsely asserting itself to be rooted in biological fact, have long been cited and are still cited in order to account for these supreme tragedies of history. =The fallacy of racial senility.=--The first may claim Plato and Aristotle as its founders, and consists of an argument from analogy. Races may be conceived in similar terms to individuals. There are many resemblances between a society--a “social organism,” to use Herbert Spencer's phrase--and an individual organism. Just, then, as the individual is mortal, so is the race. Each has its birth, its period of youth and growth, its maturity, and, finally, its decadence, senility and death. So runs the common argument. We must reply, however, that biology, so far from confirming it, declares as the capital fact which contrasts the individual and the race that, whilst the individual is doomed to die from inherent causes, the race is naturally immortal. The tendency of life is not to die but to live. If individuals die, that is doubtless because, as I believe, more life and fuller is thus attained than if life bodied itself in immortal forms: but the germ-plasm is immortal; it has no inherent tendency either to degenerate or to die. Species exist and flourish now which are millions of years older than mankind. “The individual withers, the race is more and more.”