It is strange how differently we can experience the same event at different stages of life. On 11 September 2001, I was 29 and working for an American publishing company. Our head office was in Illinois, and I remember so clearly that afternoon in our UK office when our connection with the US simply disappeared. Emails stopped, communication went quiet and, gradually, we began to understand that something terrible was unfolding. Like so many people, I watched the images from New York on...

I’m writing this from the Highlands of Scotland, where the first thing that has really struck me is the quiet. There is very little traffic noise, no constant hum of activity and far fewer sounds competing for my attention. At first, the silence feels almost startling. Then, gradually, you begin to realise that it isn’t silent at all. There is the wind moving through the trees. Water running over stones. A bird calling from much farther away than you would normally be able to hear. The sound...

Before you read any further, and if you’re at home, I’d like you to try something. Sit down on the floor. Now stand back up again. Go on… I’ll wait. How did that feel? Perhaps you stood up without a second thought. Perhaps you used your hands. Perhaps one knee complained a little, or you paused halfway to work out the best route back to standing. There’s no judgement here, it’s simply a quiet observation. We have all sorts of ways to measure our health these days. Smart watches tell us how...