A shopkeeper can watch a child become an adult through purchases too brief to feel like years.

Change becomes invisible when you see it often enough. The shopkeeper watched a child grow up entirely in two-minute instalments, none of which felt like time passing, and the whole transformation happened without a single visible moment of it. Slow change hides inside frequent contact.

So look deliberately at the people you see most. Photographs from a few years ago will show you what daily proximity conceals. It is worth doing for yourself as well, since the gradual changes in your own life, good and bad, are exactly the ones you are least equipped to notice.