I dedicate this little book to the young idealists of this and other countries, for several reasons. They must, obviously, be young, because their older contemporaries, with a large amount of experience of earlier conditions, will hardly have the courage to deal with the novel data. I take it that, after the conclusion of the present war, there will come an uneasy period of exhaustion and anxiety when we shall be told that those who hold military power in their hands are alone qualified to act as saviours of society.