I have frequently gained my first real insight into the character of parents by studying their children.

He [Professor Moriarty] is the Napoleon of crime, Watson. He is the organizer of half that is evil and of nearly all that is undetected in this great city. He is a genius, a philosopher, an abstract thinker. He has a brain of the first order.

One forms provisional theories and waits for time or fuller knowledge to explode them. A bad habit, Mr. Ferguson, but human nature is weak. Sherlock Holmes speaking with Dr. Watson.

Violence is sometimes a duty.

One must wait till it comes.

Just as an octopus may have his den in some ocean cave, and come floating out a silent image of horror to attack a swimmer, so I picture such a spirit lurking in the dark of the house which he curses by his presence, and ready to float out upon all whom he can injure.

...it is only when a man goes out into the world with the thought that there are heroisms all round him, and with the desire all alive in his heart to follow any which may come within sight of him, that he breaks away... from the life he knows, and ventures forth into the wonderful mystic twilight land where lie the great adventures and the great rewards.