Unless we are all mad, there is at the back of the most bewildering business a story: and if we are all mad, there is no such thing as madness. If I set a house on fire, it is quite true that I may illuminate many other people's weaknesses as well as my own. It may be that the master of the house was burned because he was drunk; it may be that the mistress of the house was burned because she was stingy, and perished arguing about the expense of the fire-escape. It is, nevertheless, broadly true ...