Last week I was visited at work by a reader from Malaysia who was passing through London. I am not always nice to strangers but I was curious about this one. For three years she has been emailing me about my columns – and yet she is not quite 12 years old.

When this child – who turned out to be charming and poised – had left, I started thinking about my own (much older) children. Their manners and curiosity about the world suddenly seemed wanting – as did their appetite for reading the FT (written not only in their mother tongue but partly by their mother).

To prevent a pointless where-did-I-go-wrong wallow, I turned for distraction to Twitter, where someone I follow but don’t much like was triumphantly tweeting the publication of a new book. I expanded the tweet and saw a dozen replies saying “Can’t wait to read this” and “if it’s even half as good as the last one?.?.?.?!” after which I grimly clicked through to Amazon to see the book’s sale’s rank. The knot in my belly loosened: it was 24,358.