The idea that nurses were masturbating clueless men to orgasm as a mainstream medical therapy is obviously ridiculous. But why don’t we think the same story is absurd when it’s about women? In part it’s because women have historically been seen as ignorant about their own bodies, and female sexuality has been controlled and constrained by men throughout history. In contrast, men are viewed as knowledgeable about their bodies — at least knowledgeable enough to know when they’ve had an orgasm.

Yet Ms. Maines’s story was embraced not by sexist men but by feminist women. Why? The story has the benefit of being both sexy and reassuring. It portrays sexual knowledge as marching on a steady line of progress, from clueless Victorians to today’s sexual sophisticates. It also serves as a feminist fairy tale of sorts, in which women subvert patriarchal society by procuring orgasms from their doctors, paid for by their husbands.

Ms. Maines is right about one thing: the electric vibrator was invented by a physician, the British doctor Joseph Mortimer Granville. But when Dr. Granville invented the vibrator in the early 1880s, it was not meant to be used on women or to cure hysteria. In fact, he argued specifically that it shouldn’t be used on hysterical women; rather, Dr. Granville invented the vibrator as a medical device for men, to be used on a variety of body parts, mainly to treat pain, spinal disease and deafness. The only sexual uses he suggested were vibrating men’s perineums to treat impotence. Illustrations in Dr. Granville’s book on the invention of the electric vibrator show him using it only on men.

The true story is that the use of vibrators became widespread only when they were marketed to the general public, both men and women, as domestic and medical appliances in the early 1900s. Ads featuring men and women, babies and older people, promised vibrators could do everything from eliminating wrinkles to curing tuberculosis. When doctors did use vibrators on women, they assiduously avoided touching their clitorises. “The greatest objection to vibration thus applied is that in overly sensitive patients it is liable to cause sexual excitement,” the gynecologist James Craven Wood wrote in 1917. If, however, he continued, “the vibratode is kept well back from the clitoris, there is but little danger of causing such excitement.”

It was female consumers who embraced their erotic potential — covertly at first, until the early 1970s, when the radical feminist Betty Dodson began openly using vibrators as sexual devices in her masturbation workshops.

The myth of the vibrator has real consequences. The harmful idea that women are naturally sexually ignorant and that women who do have sexual knowledge and drives are outliers, has been the basis for repressive laws throughout history: from adultery laws that punished only women to honor killings to recent restrictions on birth control and abortion. All these laws and violence are about punishing women who have sex for pleasure, not procreation.

The myth also reinforces the false idea that the history of sex moves on a straight line from repression to enlightenment. This belief can make people complacent, believing that we have advanced beyond Victorian attitudes. Yet we still live in a sexually repressive era where double standards abound: Sex toy advertising is restricted by the M.T.A., Facebook, Instagram, and other venues, while ads for erectile dysfunction products are allowed. The Trump administration has decreased sex education funding, promoted abstinence-only education, and redirected funds for preventing teen pregnancy to anti-abortion groups.

It’s time to be honest about our past: doctors didn’t invent vibrators because their wrists hurt from rubbing hysterical women’s clitorises. They invented vibrators as cure-all devices; those devices ended up curing very little, until our great-great-grandmothers put them toward their highest purpose. The real story isn’t as salacious as the myth, but it does have one important thing going for it: it happens to be true.

Hallie Lieberman is a sex historian and the author, most recently, of “Buzz: The Stimulating History of the Sex Toy.” She is at work on a book about the history of gigolos.

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