As Paul Cézanne once said, “Monet is only an eye — but my god, what an eye”:
In the 1910s, however, Monet’s vaunted eyes came under threat. He developed cataracts and, painfully, slowly, began going blind. He admitted to friends that he would likely have to quit painting soon, and the thought crushed him: for Monet, life without painting was no life at all.
There was one hope, however—surgery to remove the cataracts. Unfortunately, this procedure was not the routine operation of today; it carried great risk. Monet had in fact seen his friend and fellow artist Mary Cassatt effectively go blind after two failed cataract surgeries; she never picked up a brush again.
Eventually, though, with his artistic life at stake, Monet screwed up the courage to go under the knife. And remarkably, the surgery introduced a whole new phase in his career, because it seemingly changed how his vision worked. Already a master of color, he may have gained the ability to see color beyond the normal human spectrum—and peer into the realm of the ultraviolet.
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Cataracts arise when proteins build up on the lens of the eye, proteins that turn the lens yellow and block or scatter light. People can develop cataracts for multiple reasons, including old age, but with Monet, some historians speculate that the lead-based paints he used might have contributed.
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Because cataracts can cause glare, he had to wear floppy straw hats outdoors now. And he could paint only near dawn and dusk, when the light was gentlest.
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Instead of the fine, intricate strokes he used before, his brushstrokes now became coarse and thick. There was no more light touch, no more airiness. His color schemes changed as well. He especially had trouble seeing “cool” colors, such as blue and green: water lilies looked brownish now, and ponds looked like stagnant swamps.
As things got worse, Monet tried to make up for the muted greens and blues by dialing other colors up—fiery reds and yellows.
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But things got so bad that, by 1922, Monet could barely tell certain hues apart. He had to label his paint tubes with big block letters, and then put the paint in the same spot on his palette every day simply to find it.
Eventually, Monet had no choice but to face the dreaded surgery. It took place in January 1923. The doctors operated on one eye only (most sources say the right), so in case something went wrong, he’d have a backup eye. During recovery, he had to lie absolutely still for days, his head jammed between heavy sandbags to make sure he couldn’t move. Then for weeks afterward he had to wear bandages around his eye, which itched like crazy.
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His eye healed, and in 1924 he finally got a new pair of glasses specially crafted for postoperative cataract patients. The glasses were expensive: a single pair cost as much as a four-room luxury apartment.
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Dogs can’t see red because their cones can’t detect it. In contrast, human cones can perceive UV light if given the chance. It’s faint, but it’s there.
What prevents us from seeing UV light is our lenses, which filter it out. But when Monet’s lens was removed, that constraint was lifted. His work from this period suggests he may have been able to perceive that mysterious bee purple. To insects, water lilies would have a violet aura, and sure enough, Monet started rendering the flowers with overtones of blue and purple.
Eye surgeons still remove the lenses of cataract patients today, and usually replace them with artificial lenses that block UV light. But prior to the 1980s the lenses did not block out UV rays, and not everyone gets the lenses anyway. As a result, such people can often perceive that secret world of spotted butterflies and swirly flowers. More prosaically, people at pubs suddenly notice the ultraviolet black lights that bartenders use to weed out counterfeit bills.
I stumbled across this phenomenon years ago.