“Depend upon it, there is nothing so unnatural as the commonplace.”

“The public, not unnaturally, goes upon the principle that he who would heal others must himself be whole.”

“My life is spent in one long effort to escape from the commonplaces of existence. These little problems help me to do so.”

“As a rule, the more bizarre a thing is the less mysterious it proves to be. It is your commonplace, featureless crimes which are really puzzling, just as a commonplace face is the most difficult to identify.”

“There are strange red depths in the soul of the most commonplace man.”

“It is not really difficult to construct a series of inferences, each dependent upon its predecessor and each simple in itself. If, after doing so, one simply knocks out all the central inferences and presents one's audience with the starting-point and the conclusion, one may produce a startling, though perhaps a meretricious, effect.”

“We would not dare to conceive the things which are really mere commonplaces of existence.”