The wisest thing in the world is to cry out before you are hurt. It is no good to cry out after you are hurt; especially after you are mortally hurt. People talk about the impatience of the populace; but sound historians know that most tyrannies have been possible because men moved too late. It is often essential to resist a tyranny before it exists. It is no answer to say, with a distant optimism, that the scheme is only in the air. A blow from a hatchet can only be parried while it is in the air. There exists to-day a scheme of action, a school of thought, as collective and unmistakable as any of those by whose grouping alone we can make any outline of history. It is as firm a fact as the Oxford Movement, or the Puritans of the Long Parliament; or the Jansenists; or the Jesuits. It is a thing that can be pointed out; it is a thing that can be discussed; and it is a thing that can still be destroyed. It is called for convenience "Eugenics"; and that it ought to be destroyed I propose to prove in the pages that follow. I know that it means very different things to different people; but that is only because evil always takes advantage of ambiguity.