"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."
"What was it, then? Treason?" asked Flambeau, resuming his dinner.
"I don't know that either," answered Brown, with a face of blank bewilderment. "The only thing I can think of .... Well, I never understood that Dreyfus case. I can always grasp moral evidence easier than the other sorts. I go by a man's eyes and voice, don't you know, and whether his family seems happy, and by what subjects he chooses—and avoids. Well, I was puzzled in the Dreyfus case. Not by the horrible things imputed both ways; I know (though it's not modern to say so) that human nature in the highest places is still capable of being Cenci or Borgia. No; what puzzled me was the sincerity of both parties. I don't mean the political parties; the rank and file are always roughly honest, and often duped. I mean the persons of the play. I mean the conspirators, if they were conspirators. I mean the traitor, if he was a traitor. I mean the men who must have known the truth. Now Dreyfus went on like a man who knew he was a wronged man. And yet the French statesmen and soldiers went on as if they knew he wasn't a wronged man but simply a wrong 'un. I don't mean they behaved well; I mean they behaved as if they were sure. I can't describe these things; I know what I mean."
"I wish I did," said his friend. "And what has it to do with old Hirsch?"
"Suppose a person in a position of trust," went on the priest, "began to give the enemy information because it was false information. Suppose he even thought he was saving his country by misleading the foreigner. Suppose this brought him into spy circles, and little loans were made to him, and little ties tied on to him. Suppose he kept up his contradictory position in a confused way by never telling the foreign spies the truth, but letting it more and more be guessed. The better part of him (what was left of it) would still say: 'I have not helped the enemy; I said it was the left drawer.' The meaner part of him would already be saying: 'But they may have the sense to see that means the right.' I think it is psychologically possible—in an enlightened age, you know."
"It may be psychologically possible," answered Flambeau, "and it certainly would explain Dreyfus being certain he was wronged and his judges being sure he was guilty. But it won't wash historically, because Dreyfus's document (if it was his document) was literally correct."
"I wasn't thinking of Dreyfus," said Father Brown.
Silence had sunk around them with the emptying of the tables; it was already late, though the sunlight still clung to everything, as if accidentally entangled in the trees. In the stillness Flambeau shifted his seat sharply—making an isolated and echoing noise—and threw his elbow over the angle of it. "Well," he said, rather harshly, "if Hirsch is not better than a timid treason-monger ..."
"You mustn't be too hard on them," said Father Brown gently. "It's not entirely their fault; but they have no instincts. I mean those things that make a woman refuse to dance with a man or a man to touch an investment. They've been taught that it's all a matter of degree."
"Anyhow," cried Flambeau impatiently, "he's not a patch on my principal; and I shall go through with it. Old Dubosc may be a bit mad, but he's a sort of patriot after all."
Father Brown continued to consume whitebait.
Something in the stolid way he did so caused Flambeau's fierce black eyes to ramble over his companion afresh. "What's the matter with you?" Flambeau demanded. "Dubosc's all right in that way. You don't doubt him?"
"My friend," said the small priest, laying down his knife and fork in a kind of cold despair, "I doubt everything. Everything, I mean, that has happened to-day. I doubt the whole story, though it has been acted before my face. I doubt every sight that my eyes have seen since morning. There is something in this business quite different from the ordinary police mystery where one man is more or less lying and the other man more or less telling the truth. Here both men .... Well! I've told you the only theory I can think of that could satisfy anybody. It doesn't satisfy me."
"Nor me either," replied Flambeau frowning, while the other went on eating fish with an air of entire resignation. "If all you can suggest is that notion of a message conveyed by contraries, I call it uncommonly clever, but ... well, what would you call it?"
"I should call it thin," said the priest promptly. "I should call it uncommonly thin. But that's the queer thing about the whole business. The lie is like a schoolboy's. There are only three versions, Dubosc's and Hirsch's and that fancy of mine. Either that note was written by a French officer to ruin a French official; or it was written by the French official to help German officers; or it was written by the French official to mislead German officers. Very well. You'd expect a secret paper passing between such people, officials or officers, to look quite different from that. You'd expect, probably a cipher, certainly abbreviations; most certainly scientific and strictly professional terms. But this thing's elaborately simple, like a penny dreadful: 'In the purple grotto you will find the golden casket.' It looks as if ... as if it were meant to be seen through at once."
Almost before they could take it in a short figure in French uniform had walked up to their table like the wind, and sat down with a sort of thump.
"I have extraordinary news," said the Duc de Valognes. "I have just come from this Colonel of ours. He is packing up to leave the country, and he asks us to make his excuses sur le terrain."
"What?" cried Flambeau, with an incredulity quite frightful—"apologize?"
"Yes," said the Duke gruffly; "then and there—before everybody—when the swords are drawn. And you and I have to do it while he is leaving the country."
"But what can this mean?" cried Flambeau. "He can't be afraid of that little Hirsch! Confound it!" he cried, in a kind of rational rage; "nobody could be afraid of Hirsch!"
"I believe it's some plot!" snapped Valognes—"some plot of the Jews and Freemasons. It's meant to work up glory for Hirsch ..."
The face of Father Brown was commonplace, but curiously contented; it could shine with ignorance as well as with knowledge. But there was always one flash when the foolish mask fell, and the wise mask fitted itself in its place; and Flambeau, who knew his friend, knew that his friend had suddenly understood. Brown said nothing, but finished his plate of fish.
"Where did you last see our precious Colonel?" asked Flambeau, irritably.
"He's round at the Hotel Saint Louis by the Elysée, where we drove with him. He's packing up, I tell you."
"Will he be there still, do you think?" asked Flambeau, frowning at the table.
"I