In 1937 a painting appeared in the Netherlands that answered a question the country's most eminent art historian had been asking for years.
Abraham Bredius had argued that Vermeer must have had an early religious period, influenced by Italian painting, of which no works survived. It was a theory, and it was published.
Christ at Emmaus was presented to him as a newly discovered Vermeer. Bredius authenticated it in the Burlington Magazine in language that has not aged well: it was, he wrote, the masterpiece of Johannes Vermeer of Delft, quite different from all his other paintings and yet every inch a Vermeer, and — the sentence that did the damage — we have here, I am inclined to say, the masterpiece of Johannes Vermeer.
It was painted by Han van Meegeren, a Dutch portraitist embittered by critics who had dismissed his own work as derivative.
The technique that fooled the physical tests was serious craft. Van Meegeren bought genuine seventeenth-century canvases and removed the existing images while preserving the ground and the craquelure. He ground his own pigments to period recipes. His central problem was that oil paint takes decades to harden, and a solvent test would dissolve a recent painting; he solved it by mixing his pigments with a phenol-formaldehyde resin — an early plastic — and baking the finished canvas, producing a surface that resisted solvents as an aged painting does. He rolled the canvas to crack the paint and worked Indian ink into the cracks to simulate centuries of dirt.
But the craft is not why it worked, and van Meegeren himself understood this. He painted the picture that Bredius had predicted.
This is confirmation bias in its purest documented form. Bredius was not shown a painting and asked to evaluate it. He was shown the evidence for his own theory, and the evaluation was made by a man with a prior he wanted confirmed and a reputation attached to it. Once the attribution was published, dissonance reduction did the rest: an authority who has staked his standing on an attribution has a strong motive to defend it, and other experts deferred to Bredius rather than to the object.
Six more forgeries followed, sold for enormous sums. One went to Hermann Göring, in an exchange for Dutch paintings that Göring had looted.
Which produced the ending. After the liberation, van Meegeren was arrested for collaboration — for selling a Dutch national treasure to the enemy, a capital offense. His defense was that it was not a national treasure because he had painted it. Nobody believed him, so under guard, in a studio, over six weeks, he painted another one.
He was convicted of forgery in 1947 and sentenced to a year. He died of a heart attack before serving it, and was for a period a popular hero.