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

Healthy scepticism is the basis of all accurate observation.

Well, sir, let us do what we can to curtail this visit, which can hardly be agreeable to you, and is inexpressibly irksome to me.

I had ... come to an entirely erroneous conclusion, which shows, my dear Watson, how dangerous it always is to reason from insufficient data.

Eliminate all other factors, and the one which remains must be the truth.

There was a brisk northern wind, heavy and wet with the salt of the sea, and he felt, as he turned his face to it, fresh life and strength surging in his blood and bracing his limbs.

The most serious point in the case is the disposition of the child." What on earth has that to do with it?" I ejaculated. My dear Watson, you as a medical man are continually gaining insight as to the tendencies of a child by the study of the parents. Don't you see that the converse is equally valid. I have frequently gained my first real insight into the character of parents by studying their children.