To say that Agatha Christie’s characters are cardboard cut-outs is an insult to cardboard cut-outs.

The trouble with psychology is that it doesn't take human nature into account.

I can't exist without books.

When one has children one has no privacy. They take it for granted that what is yours is theirs, personal things and the secrets of your heart, as well as possessions.

We no more forget the faces of our enemies than of those we love.

the English, although partakers in the most variable and quixotic climate in the world, never become used to its vagaries, but comment upon them with shock and resentment as if all their lives had been spent in the predictable monsoon.

Eunice Parchman killed the Coverdale family because she could not read or write.