Poirot," I said. "I have been thinking." "An admirable exercise my friend. Continue it.

Nobody knows what another person is thinking. They may imagine they do, but they are nearly always wrong.

All I needed was a steady table and a typewriter...a marble-topped bedroom washstand table made a good place; the dining-room table between meals was also suitable.

Curious things, habits. People themselves never knew they had them. [Witness for the Prosecution, also published in The Hound of Death and Other Stories.]

Very few of us are what we seem.

You agree - I'm sure you agree that beauty is the only thing worth living for.

These little grey cells. It is up to them.