Nature, as we say, does nothing without some purpose; and for thepurpose of making mana political animal she has endowed him alone among the animals with the power of reasoned speech.
What I try to do is write a story about a detective rather than a detective story. Keeping the reader fooled until the last, possible moment is a good trick and I usually try to play it, but I can't attach more than secondary importance to it. The puzzle isn't so interesting to me as the behavior of the detective attacking it.