‘Willie or bum?’ I said to Catriona on the motorway. Everything in my recent medical career has been introduced via the former: cameras, cutters, stents. I naturally assumed it would be the same choice of pathways for exploring and snipping off three pieces of my liver. At the wheel, Catriona laughed at my idiocy and explained where my liver was and that there was not a pathway from it to either of those entrances.