In broad terms, BMW's designers get their ideas from the world around them - though not from the world of cars. "If I were to list my influences in car design, I'm afraid you'd have to think pretty synthetically to make sense of them," says Bangle. "Architecture, airplanes, boats, botany, cathedrals, domes just go through the alphabet."
Bangle fills notebooks with cartoon-like sketches of his travels and observations, with quick captions written in German and English. There's a star chart for locating the Southern Cross; there are notes from last year's World Economic Forum, including a whimsical sketch of Hillary Clinton's begrimed high heels and a free-flowing illustration of the gateway to the Alamo in San Antonio, Texas. Tellingly, there's not a single sketch of a car. Bangle won't comment on his jottings (too personal), but as he closes the journal, he offers a cryptic bit of advice: "Take notes on the world. There will be a test."