I’ve been bingeing on Hercule Poirot on PBS lately.

Poirot, if anyone in the English-speaking world is unaware, is Agatha Christie’s funny little Belgian detective, the most celebrated fictional detective this side of Sherlock Holmes. I’ve read all the books and seen all the shows already, more than once. So now I suppose you could say I’m luxuriating in nostalgia. Poirot is always talking about the necessity of order and method in detection. One fact leads to another, forging a chain of causati...