Dan

“There were no footmarks.'
'Meaning that you saw none?'
'I assure you, sir, that there were none.'
'My good Hopkins, I have investigated many crimes, but I have never yet seen one which was committed by a flying creature. As long as the criminal remains upon two legs so long must there be some indentation, some abrasion, some trifling displacement which can be detected by the scientific searcher.”
― Arthur Conan Doyle, The Return of Sherlock Holmes

“I will not look through keyholes,” I interrupted hotly. Poirot closed his eyes. “Very well, then. You will not look through keyholes. You will remain the English gentleman and someone will be killed.”
― Agatha Christie, Curtain: Poirot's Last Case

“My remarks are, as always, apt, sound, and to the point. (Hercule Poirot)”
― Agatha Christie, The Labours of Hercules

“Violence, naked force, has settled more issues in history than has any other factor.”
― Robert A. Heinlein, Starship Troopers