In today's New York Times, Bruce Boucher, author and curator at the Art Institute of Chicago, reflects on what happens when novelists don't know their history and when readers don't notice. Dan Brown's The Da Vinci Code, a murder mystery set in the present that hinges on Leonardo's art, philosophy, and life, has ridden the New York Times best-seller list for eighteen weeks now. It has been hailed by Janet Maslin--writing for the NYT no less--as "blockbuster perfection .... an exhilaratingly brainy thriller." The Rocky Mountain News says it contains "enough medieval history to please any historian," Bookpage says that "Brown's scholarship never slows down," and the Chicago Tribune says that the book contains "several doctorates' worth of fascinating history and learned speculation" (for many more comments along these lines, see Brown's website).

But at least one expert says the book is filled with gross errors of fact and embarrassing gaffes. Brown claims to have researched the book extensively, but Boucher assembles damning evidence that Brown is neither particularly careful nor especially knowledgeable:

...the author's grasp of the historical Leonardo is shaky. One small but telling point comes in Mr. Brown's references to Leonardo as "Da Vinci," as if that were the painter's last name, yet it is no surname but simply a reference to the fact that he was the illegitimate son of Ser Piero of Vinci, in the Florentine territory. Like other great artists, with or without last names, Leonardo is invariably referred to by his given name and not by da Vinci.

The nomenclature suggests a lack of familiarity with the copious bibliography on the painter, as do Mr. Brown's references to Leonardo's "enormous output" of Christian art and "hundreds of lucrative Vatican commissions." Leonardo was, in fact, notorious for his meager production and spent little time in Rome. Neither, for that matter, is it accurate to call Leonardo a "flamboyant homosexual": despite a charge of sodomy against him as a young man, the evidence of his sexual orientation remains inconclusive and fragmentary.

It is also breathtaking to read that the heroine, Sophie Neveu, uses one of Leonardo's paintings, "The Madonna of the Rocks," as a shield, pressing it so close to her body that it bends. More than six feet tall and painted on wood, not canvas, the "Madonna" is unlikely to be so supple. But that may be poetic license on Mr. Brown's part; even the legendary connoisseur Bernard Berenson was uncertain whether Leonardo painted on wood or canvas.

As Brown counts his royalties, he ought to be squirming. So should his editor.