G. K. Chesterton: The Wisdom of Father Brown

3. The Duel of Dr Hirsch (continued)

"I'm frightened of a white envelope," said the other seriously, "If it had only just been grey! Hang it all, it might as well have been grey. But if it was white, the whole business is black. The Doctor has been dabbling in some of the old brimstone after all."

"But I tell you he couldn't have written such a note!" cried Flambeau. "The note is utterly wrong about the facts. And innocent or guilty, Dr Hirsch knew all about the facts."

"The man who wrote that note knew all about the facts," said his clerical companion soberly. "He could never have got 'em so wrong without knowing about 'em. You have to know an awful lot to be wrong on every subject--like the devil."

"Do you mean--?"

"I mean a man telling lies on chance would have told some of the truth," said his friend firmly. "Suppose someone sent you to find a house with a green door and a blue blind, with a front garden but no back garden, with a dog but no cat, and where they drank coffee but not tea. You would say if you found no such house that it was all made up. But I say no. I say if you found a house where the door was blue and the blind green, where there was a back garden and no front garden, where cats were common and dogs instantly shot, where tea was drunk in quarts and coffee forbidden--then you would know you had found the house. The man must have known that particular house to be so accurately inaccurate."

"But what could it mean?" demanded the diner opposite.

"I can't conceive," said Brown; "I don't understand this Hirsch affair at all. As long as it was only the left drawer instead of the right, and red ink instead of black, I thought it must be the chance blunders of a forger, as you say. But three is a mystical number; it finishes things. It finishes this. That the direction about the drawer, the colour of ink, the colour of envelope, should none of them be right by accident, that can't be a coincidence. It wasn't."