When the fact doesn't meet the theory then let go the theory. - Agatha Christie

If I were at any time to set out on a career of deceit, it would be of Miss Marple that I should be afraid.

I've never met a murderer who wasn't vain... It's their vanity that leads to their undoing, nine times out of ten. They may be frightened of being caught, but they can't help strutting and boasting and usually they're sure they've been far too clever to be caught.

It was the technique of a man who selected thoughts as one might select pieces of a jigsaw puzzle. In due course they would be reassembled together so as to make a clear and coherent picture. At the moment the important thing was the selection, the separation.