John had been put through an immense variety of paces, and had answered volumes of head-breaking questions.

During the Second World War Turing worked at Bletchley Park, Britain's code-breaking centre, and was for a time head of Hut 8, the section responsible for German naval cryptanalysis.

Mr Cox muses about breaking out of the age straitjacket to mix eight-, ten-, and 15-year-old stock under a label such as “head distiller’s choice”.