The Technique of the Mystery Story

-"The Thinking Machine," aside from his petulance and impatience, continually repeats two or three favorite phrases that annoy the reader quite as much as the clients annoy this astute detective. One of them is, "Don't say it is impossible! that annoys me exceedingly! Nothing is impossible to the human mind!" This assertion, innocent enough in itself, is so frequently repeated as to become intolerable. Another phrase of which Professor Van Dusen is inordinately fond, is, "Two and two make four, not sometimes, but all the time." This also is repeated so often as to become tiresome. To quote the Professor: "Two and two make four, not sometimes, but all the time," he began, at last as if disputing some previous assertion. "As the figure two, wholly disconnected from any other, gives small indication of a result, so is an isolated fact of little consequence. Yet that fact added to another, and the resulting fact added to a third, and so on, will give a final result. That result, if every fact is considered must be correct. Thus any problem may be solved by logic; logic is inevitable."

Indeed, variations on a theme of two and two making four are hackneyed in detective fiction.