We balance probabilities and choose the most likely. It is the scientific use of the imagination.

It is stupidity rather than courage to refuse to recognize danger when it is close upon you.

Beyond the obvious facts that he has at some time done manual labour, that he takes snuff, that he is a Freemason, that he has been in China, and that he has done a considerable amount of writing lately, I can deduce nothing else.

I consider that a man's brain originally is like a little empty attic, and you have to stock it with such furniture as you choose.

The Press, Watson, is a most valuable institution, if you only know how to use it.

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

So swift, silent and furtive were his movements like those of a trained bloodhound picking out a scent, that I could not but think what a terrible criminal he would have made had he turned his energy and sagacity against the law instead of exerting them in its defense. -Dr. Watson, The Sign of the Four