[...] forgers teach us to doubt connoisseurs. There’s a myth out there, propagated by the market and some strains of academe, that certain thoroughbred experts can smell authentic art at 100 yards. After more than a century of bad attributions, reattributions and long-lived fakes, you’d think we would know better than to believe in such fantasy creatures. The truth is, the connoisseur’s eye works brilliantly in that vast majority of attributions where an artwork comes without a name attached but clearly has a single maker’s signature look. And then that eye fails utterly in those remaining, more iffy cases where a piece looks quite like some artist’s work, but may almost as easily be by someone else — including a forger.

Every time an expert is fooled by a fake, the faker has once again taught us that connoisseurship is not to be trusted. More important, we’re reminded that the whole idea of a unique artistic “touch,” along with the ideal of “authenticity” that goes with it, may be beside the point in our understanding of art.

Time destroys fakes by revealing features of the era—the climate of taste—in which they were made. “Forgeries must be served hot,” said the art historian Max Friedländer. I’ve seen two “Vermeers” that were painted in the nineteen-twenties by the king of modern forgers, the Dutchman Han van Meegeren (1889-1947), and which hung unchallenged, for decades, in the National Gallery, in Washington, D.C. They are ridiculous. Among other blinking signs of fraudulence, there’s an interesting suggestion that the likes of flappers and Greta Garbo inhabited seventeenth-century Delft.

How could anyone ever, for a minute, have mistaken those howlers for Vermeers? That’s easy. Connoisseurs are products of their times as much as anyone else, subject to the same unexamined assumptions. But it’s usually a connoisseur who soonest smells a rat. He or she does so not by being wary but by becoming puzzled in a normal pursuit of pleasure.

What do we see when we look at a painting? Decisions. Stroke by stroke, the painter did something rather than something else, a sequence of choices that add up to a general effect. If you’re like me—and, yes, I count myself a middling connoisseur—you register the effect and then investigate how it was achieved; walking the cat back, as they say in espionage. As a trick, ask yourself, of details in a painting, something like, “Why would I have done that in that way?” The aim is to enter into the mind, and the heart, of the creator. Attaining it entails trust, like that of a child attending a fairy tale.

To deny connoisseurship is to deny that there are visually discernable differences between the work of one artist and that of another who is imitating his style.  If that were true then why buy the original if a copy or similar work is as good.

Copyists and forgers are artists and some are very good artists but the point is attribution rather than quality, and either an artists work has unique qualities or attribution of unsigned works is irrelevant except to price.

As to whether there are individuals who can recognize these unique qualities, they vary at least as much as the quality of artists' work.

This should all be obvious to anyone who looks at art.