It is not that I think or believe, but that I know.

It's a wicked world, and when a clever man turns his brain to crime it is the worst of all.

They say that genius is an infinite capacity for taking pains," he remarked with a smile. "It's a very bad definition, but it does apply to detective work.

Art in the blood is liable to take the strangest forms.

London, that great cesspool into which all the loungers and idlers of the Empire are irresistibly drained.

Watson. Come at once if convenient. If inconvenient, come all the same.

My dear Watson," said [Sherlock Holmes], "I cannot agree with those who rank modesty among the virtues. To the logician all things should be seen exactly as they are, and to underestimate one's self is as much a departure from truth as to exaggerate one's own powers.