Not that it relates to anything here but I've just been reminded of some words John Dickson Carr put into the mouth of Henri Bencolin:
A corpse (let us say) is found strangled, sitting in a chair by a window, and wearing a domino mask; and all the clocks in the house are found with their faces turned to the wall. You are carefully warned that the blazing clue to the truth is the fact that there is a teaspoon in the victim's side pocket, and that, without all these things being just as they were, the crime could never have taken place.--You follow me? No clue was left merely to confuse; or because it was a reminder of the victim's past misdeeds (that saddest device of all); or because the murderer thought it artistic. Each indication was a necessary part of the pattern."
"What's the explanation?" demanded Bryce, his face lighting up with interest.
Bencolin looked at him. "I suggest you think of one," he said politely. "Or apply yourself to a study of Rose Klonec's murder. But to finish this mask-clock-teaspoon puzzle. Now, suppose at the denouement the identity of the murderer was revealed--for the simple reason that his fingerprints matched those on the collar of the strangled man. Would you feel cheated? That's exactly what might happen in life; but would you feel cheated? You know damned well you would. There is no doubt as to the identity of the murderer. He admits the crime. Then he shoots himself. Consequently, you never know the significance of the mask or the reversed clocks, or what deduction you should have drawn from the teaspoon. Page 315, 'The End.' What would you do? You would strangle the author, lynch the publisher, and shoot the bookseller. Yet why do you complain? You know the identity of the murderer, don't you?"
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