"How small we feel with our petty ambitions and strivings in the presence of the great elemental forces of Nature!"

"I am not a connoisseur of crime; I am a student of it."

"Crime is common. Logic is rare. Therefore it is upon the logic rather than upon the crime that you should dwell."

"Never trust to general impressions, my dear Watson, but concentrate yourself upon details."

"My dear Watson, you were in my mind, just as I was in yours."