For several years, around the time I first learned to meditate, I lived in an apartment above Sauchiehall Street in Glasgow—one of the city’s main shopping streets. Sometimes it was acutely noisy, with newspaper hawkers advertising their wares, workmen digging up the roads, drunks singing as they staggered home from the pub, or couples having loud—and very public—fights. But even at the best of times there was a chronic, ongoing hum from the thousands of surrounding vehicles, and the quieter babble of pedestrians’ voices. This was something I had to get used to when I was meditating.

At first I would battle to shut out the noise, and try to force myself to focus inward …