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

I think you want a little unofficial help. Three undetected murders in one year won't do, Lestrade. But you handled the Molesey Mystery with less than your usual - that's to say, you handled it fairly well.

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.

Goresthorpe Grange is a feudal mansion - or so it was termed in the advertisement which originally brought it under my notice. Its right to this adjective had a most remarkable effect upon its price, and the advantages gained may possibly be more sentimental than real. Still, it is soothing to me to know that I have slits in my staircase through which I can discharge arrows; and there is a sense of power in the fact of possessing a complicated apparatus by means of which I am enabled to pour molten lead upon the head of the casual visitor.

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

It is a capital mistake to theorize before you have all the evidence. It biases the judgment.

Everything comes in circles. [...] The old wheel turns, and the same spoke comes up. It's all been done before, and will be again.