About twenty seconds ago, I blinked, saw a window and outside it, my next-door neighbour’s kid, Sammy. Sammy recently turned five. He was standing on the far side of the road and wanted to cross over. I knew there were no cars around without having to look, because even through the glass I’d have heard them. I grew up on this street so I’m finely tuned in to that sort of thing. But Sammy, who’s only been living here for the five years, was less sure. He solemnly checked in both directions, twice each way, and only then set off for the other side. He used measured strides because he’s so little and liable to lose balance, but to me, he looked like a miniature explosives expert, walking from the lit fuse instead of running.

Five years old. Packed with common sense. Say, eight or nine years left to go before the common sense starts to desert him. Twelve years to go until he’s in an abject free-fall, if he’s anything like me. And he could well be. At five, I was certainly the kind of kid who looked both ways before crossing the road.