It’s funny the ideas you get as a child. We were on holiday in the British seaside resort of Scarborough, and I was four years old. One day, as we walked along the promenade, I got it into my head to start dragging my left foot as I walked.

My parents were naturally concerned. My mother took me over to a convenient nearby bench and sat me down. She took off my shoe and checked there wasn’t a stone in there, then experimentally, gently rotated my ankle. I didn’t cry out in pain, so she asked: “Are you all right?” I nodded. “Then why are you limping?” I shrugged. “Well, stop it!” She smacked the top of my leg lightly.

We resumed walking along the prom but as soon as my mother’s attention was elsewhere, I began to drag my left foot again. I found I liked the attention I was getting from other passers-by on the promenade, who looked at me with mixed expressions of amusement, puzzlement and pity.