Primary school is where you first learn that there are people who can, in that time-honoured phrase of watchful adults, ‘lead you astray’. And it’s where you learn whether you are going to stay away from these people in future or if you will spend the rest of your life seeking them out, and hoping that said watchful adults will furnish forth bail money/penicillin/tattoo-removal fees as necessary.

It is through ‘trying on’ different types of people at an early stage that we learn what, and who, suits us. Friends help us form ourselves. With practice, you can hope to have arrived by your early 20s at a place populated by the people who best know you and keep you being ‘you’. Those who will tell you when the real you is becoming too drunk/big headed/fat arsed-for-those- pants – as needed.

Good friends – and the ability to make and keep them – are vital. For most of us they are our primary support. We no longer live among extended clans and divorce can fragment the immediate family. Often we don’t find a partner and begin our own family until we are in our 30s, leaving a historically unprecedented number of years and roles for our friends to fulfil. We need to learn how to make them.

When I think of a primary school with a best friend ban in place, I think of little atomised bits of society bobbing aimlessly round the playground. The fallout may be terrible at the time when you break up with your latest besty, but it’s the old Buddhist saying playing in a minor key: “Sorrow carves the cup in which you hold your joy.” Or, as Debra Winger says to Anthony Hopkins in Shadowlands; “The pain then…” (I’ll pause for readers who have seen the film to dry their eyes with me now. Ready?)… “Is part of the happiness now.” Wail.

In short, I’m afraid the poor, exhausted teachers must dig yet further into their depleted inner resources and allow their charges to experience all the highs, lows, tears and laughter of creating and losing friendships. Otherwise we will end up with a land full of emotionally cauterised and affectless stumps, which is worse – though admittedly less unsightly – than a land full of people who can’t use cutlery.

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Picture credit: Rex Features

Lucy Mangan on best friends