When I left Glasgow's Govan High School at the age of sixteen to begin my apprenticeship as a toolmaker at Remington Rand and my football life at Queen's Park FC, it would have been impossible to imagine that, 55 years later, I would be facing from an auditorium at Harvard Business School talking about me to a class of MBA students.
The first class I taught, in October 2012, was completely packed. From where I was at the front of the auditorium,...