Camera reviews are rarely occasions for existential reflection. We expect to read about what the camera can do. But the Leica M (also known as the Typ 240) elicits deeper questions: How versatile should a camera try to be? How far from the mainstream dare it stray? What sort of pictures do we want to take with it? How much should it cost? Soon we are in really deep water: What sort of people are we? Why would we (or anyone) buy an M?