When famed Impressionist artist Vincent van Gogh cut off his left ear in Arles, France, in December 1888, he may have chopped the whole thing off instead of simply slicing off a tiny piece, The New York Times reports.

Scholars had long debated the severity of van Gogh’s injury, but when author Bernadette Murphy was researching the artist’s later years for a book, she discovered new historical evidence: a letter written by Félix Rey—a doctor who treated van Gogh after he lost his ear—which contained a sketch of the mutilated organ. In the physician’s rendering, the painter had completely severed it from his head.

Some experts are skeptical of Murphy’s evidence, and say that witnesses who saw van Gogh after Dr. Rey treated him saw that he still had part of his ear. And a doctor who tended to van Gogh in 1890 made his own etching of the mangled body part. In his depiction, some of the ear’s outer portion still remains.

Aside from the ear's appearance, many aspects of the grisly incident remain a mystery more than a century later. For instance, nobody knows quite why van Gogh famously gave his ear to a woman working at a brothel, whom Murphy identified as a bar maid who had been injured by a dog. (Murphy, who tracked down the maid's living descendants while researching her book, believes van Gogh was offering her his own flesh in a misguided attempt to “heal” her wounds, The Telegraph reports.) Meanwhile, scholars still don’t know how van Gogh lost his ear, and theorize that he cut it off himself in a fit of depression, or that fellow artist and expert fencer Paul Gauguin sliced it off with a rapier after van Gogh threw a wine glass at him.

However, a new exhibit at Amsterdam’s Van Gogh Museum, “On the Verge of Insanity,” leans toward the mental illness explanation: It displays Félix Rey’s note and drawing alongside 25 paintings and previously unseen documents and artifacts, like the revolver van Gogh may have used to kill himself on July 29, 1890, in Auvers-sur-Oise, France. Together, the items paint a fuller portrait of the Dutch Impressionist’s declining mental health during the last years of his life. (Experts believe that van Gogh—who suffered from recurrent psychotic episodes, losses of consciousness, and vacillating moods—may have had temporal lobe epilepsy, bipolar disorder, or a combination of the two.)

“On the Verge of Insanity” opens on Friday, July 15 and runs until September 25. It coincides with the release of Murphy’s book, Van Gogh’s Ear: The True Story, which will be the basis of a forthcoming BBC documentary.

[h/t The New York Times]

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