Do you know anything on earth which has not a dangerous side if it is mishandled and exaggerated?

[Sherlock Holmes:] The temptation to form premature theories upon insufficient data is the bane of our profession.

The larger crimes are apt to be the simpler, for the bigger the crime, the more obvious, as a rule, is the motive.

He seems to have declared war on the King’s English as well as on the English king.

You will, I am sure, agree with me that... if page 534 only finds us in the second chapter, the length of the first one must have been really intolerable.

There are no crimes and no criminals in these days. What is the use of having brains in our profession? I know well that I have it in me to make my name famous. No man lives or has ever lived who has brought the same amount of study and of natural talent to the detection of crime which I have done. And what is the result? There is no crime to detect, or, at most, some bungling villainy with a motive so transparent that even a Scotland Yard official can see through it.

Life, it turns out, is infinitely more clever and adaptable than anyone had ever supposed.