Well, well, my dear fellow, be it so. We have shared this same room for some years, and it would be amusing if we ended by sharing the same cell. (...)

We can't command our love, but we can our actions.

When once your point of view is changed, the very thing which was so damning becomes a clue to the truth.

A man with so large a brain must have something in it.

So complex is the human spirit that it can itself scarce discern the deep springs which impel it to action.

All other men are specialists, but his specialism is omniscience.

A study in scarlet, eh? Why shouldn't we use a little art jargon? There's the scarlet thread of murder running through the colourless skein of life, and our duty is to unravel it, and isolate it, and expose every inch of it.