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

What can we know? What are we all? Poor silly half-brained things peering out at the infinite, with the aspirations of angels and the instinct of beasts.

I have mastered the principles of several religions. They have all shocked me by the violence which I should have to do to my reason to accept the dogmas of any one of them.

I think there are certain crimes which the law cannot touch, and which therefore, to some extent, justify private revenge.

It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth.

By the way, Doctor, I shall want your cooperation.' 'I shall be delighted.' 'You don't mind breaking the law?' 'Not in the least.' 'Nor running a chance of arrest?' 'Not in a good cause.' 'Oh, the cause is excellent!' 'Then I am your man.' 'I was sure that I might rely on you.

My sister and I, you will recollect, were twins, and you know how subtle are the links which bind two souls which are so closely allied.