One by one, down they fall on their feet of clay. The latest liberal icon to be revealed in his true colours is Arthur Miller, theatrical voice of the tortured American psyche and “the moralist of a generation”, as The Guardian, speaking for the liberal intelligentsia who so revered Miller, puts it.

Miller turns out to have been a prize s**t. In 1967, Miller committed his week-old Down’s syndrome son to an institution and wiped all trace of the boy’s existence from his life.

The moral compass of his nation, eh? Cue angst-ridden pieces on the need to reassess his work.

His biographer, Christopher Bigsby, has pointed out: “Miller’s work is precisely about such flawed men and women. In The Crucible a courageous public stance is taken by a man whose private behaviour is fallible . . . What are Willy Loman and Eddie Carbone, in Death of a Salesman and A View from the Bridge, if not men struggling to do right while unsure what form right action might take?”

Miller’s private behaviour may, as Professor Bigsby implies, have added depth and insight to his work, but it is entirely irrelevant to its worth. Yes, we can understand more about a work of art when we understand more about its creator – Shostakovich’s Seventh Symphony is given an added dimension when we know that it was written in 1941, is called “The Leningrad” and was intended to mark the suffering of the city in the siege. But as a piece of art, it stands or falls on its own merit.

Take two composers: Richard Wagner and Tikhon Khrennikov. Wagner was one of the most unpleasant men to have walked the earth. Bigoted, amoral and arrogant in the extreme, if his personality and morals were to be included in a judgment on his operas they would lie forgotten in the gutter. But for all his personal defects, he was also one of the world’s artistic geniuses, whose operas represent the peak of 19th-century artistic achievement.

Tikhon Khrennikov, a Russian composer who died last month, was an equally repugnant human being. In 1948 he was appointed Secretary of the Union of Soviet Composers, a post he held until the collapse of the Soviet Union and from which he exercised an entirely malign influence, destroying composers who did not pay due heed to the credo of Soviet communism. He was also a terrible composer.

Judge and condemn his life, yes. And judge and condemn his music, too. But the two condemnations ought not to be linked in any way. Had his pieces been worth posterity’s attention, his moral failings would have been irrelevant.

The Miller revelation shows how fatuous judging artistic worth on the basis of artists’ behaviour can be. When Miller took his decision, attitudes to Down’s syndrome were different. What does that have to do with Willy Loman?

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