John Sainsbury never liked that pillar. It was structurally unimportant and, he believed, an eyesore to the visitors that would eventually stroll through the foyer of the Sainsbury Wing of the National Gallery in London, to which Mr. Sainsbury’s family had reportedly donated tens of millions of pounds.

False pillars were installed in the gallery’s entrance anyway, part of the postmodern construction of the American architects Robert Venturi and Denise Scott Brown, who designed the Sainsbury Wing in 1990. Mr. Sainsbury died in 2022 still never having liked the design, an elite grievance that might have been lost to history.

But he really hated that pillar.

And 33 years later, he got the last word: posthumously, in a letter pulled last year from the rubble as demolition crews began remodeling the wing — sans column.

“If you have found this note you must be engaged in demolishing one of the false columns that have been placed in the foyer of the Sainsbury Wing,” said the letter, written on 1990 Sainsbury stationary and wrapped in plastic. “Let it be known that one of the donors of this building is absolutely delighted that your generation has decided to dispense with the unnecessary columns.”

In an era where the petty gripes of billionaires can veer into the outrageous, exorbitant or just plain absurd, Mr. Sainsbury’s successful analog trolling offers a more relatable stunt. We can’t all build competing spaceships or purchase warring social media platforms, but we all have pen and paper. Who among us wouldn’t love such delayed vindication, plucked from the debris of our nemeses?