There is a game outlined in David Lodge’s novel Changing Places in which thrusting academics humiliate one another with what they haven’t read.

A similar game is played nightly among London’s chattering classes. To compete, you must evolve the ability to talk about stuff you have never seen, based solely on a couple of lines you once read in a newspaper — and on no account should you disclose that you have never actually seen The Godfather, or visited the Tate, or listened to Mahler.

Turning up to the 50th anniversary performance of Harold Pinter’s The Birthday Party I was in a potentially embarrassing position. For despite having chuckled at jokes about Pinter’s pauses and possibly having dropped the word “Pinteresque” into conversation, I had never actually seen any of his plays. In certain theatrical circles, this is the kind of thing they chisel onto your gravestone, like “fell asleep in Lear” and “didn’t get Beckett”.

In reality, though, I was in for the grandest treat of all, for I found the Birthday Party fresh in a way I would never have expected of a play so canonical, hilarious for something I imagined was forbiddingly serious.

I loved the way sentimentality mingled with menace. I actually snorted when Sheila Hancock’s Meg declared “This is lovely!” as a cruel game of blind man’s buff played out in her grimy boarding house.

I could see how Pinter drew the line from kitchen sink dramas to the theatre of the absurd, and how his black humour, that so perplexed the critics 50 years ago, had become second nature to me without my really knowing its provenance.

I realised that Martin McDonagh, whose play The Pillowman I thought startlingly original in 2003, had cribbed most of his ideas from Pinter. In short, The Birthday Party was the best thing I’ve seen in ages — and doubly moving for the presence of the playwright himself in the audience.

Of course, it goes without saying that afterwards a Pinter veteran told me that in his view this production wasn’t nearly as good as the one at the National some years ago. But that only underlines my point — that not having read or seen or heard something terrific is a position to envy rather than scorn.

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