"To all those who I do not know, and who live in the worlds where superstition and barbarism are still dominant, and into whose hands I hope this little book may fall, I offer the modest encouragement of an older wisdom. It is in fact this, and not any arrogant preaching that come to us out of the whirlwind: "Die stimme der vernunft ist leise". Yes, The voice of reason is very soft, but it is very persistent. In this, and in the lives and minds of combatants known and unknown, we repose our chief hope."