Agatha Christie's creations are aspirational to many competitive intelligence analysts. Certainly they are to us, and our website features some quotations from the likes of Poirot. A common link between Christie, Poirot and competitive intelligence analysts is that we all rely on our own mental faculties for earning a living.
A couple of years ago, some researchers at the University of Toronto analyzed how Christies's vocabulary diminished with age, to suggest that she had Alzheimer's. The conclusions make for interesting reading.