I'm discovering a new jealousy in myself as the years pass — I'm becoming very possessive of my time, especially if I think it's being wasted.

Recently I left a movie early when I finally decided that it had become too outrageous to be funny any more. And I've discovered that I'm not alone.

Sometimes we may trust one person but not another without being able to explain precisely why.

Many people my age share my intolerance of time-wasting activities, and like me, have started to leave unsatisfactory lectures, films and concerts before the end.

They've also stopped reading mid-book and switching off mid-app – because they have better ways to spend their time.