The average man has a carefully cultivated ignorance about household matters - from what to do with the crumbs to the grocer's telephone number - a sort of cheerful inefficiency which protects him.
Crime stories are our version of sitting round a camp fire and telling tales. We enjoy being scared under safe circumstances. That's why there's no tradition of crime writing in countries that have wars.
The first point of wisdom is to discern that which is false; the second, to know that which is true.

