There is no shortage of feel-good inspirational quotes attributed to Helen Keller. “Never bend your head, hold it high. Look the world straight in the eye,” one of them goes. “Keep your face in the sunshine and you cannot see a shadow,” instructs another. Or, “Optimism is the faith that leads to achievement.”

Perhaps less catchy and sentimental, and certainly less well known, are the numerous observations on inequality, poverty and class that Keller made during her lifetime as a socialist activist. “Yours for the revolution!” she declared, in a 1919 letter to Industrial Workers of the World (IWW) founder Eugene Debs. “May it come swiftly,” she continued, “like a shaft sundering the dark!”

The popular narrative of Helen Keller—born 135 years ago this weekend, on June 27, 1880—is a classic American story about triumphing in the face of adversity, which emphasizes individual determination over political action. But Keller’s true legacy also includes a commitment to socioeconomic justice, which she saw as instrumental to improving the lives of people with disabilities.

In 1933, TIME described Keller as a “blind-deaf mute who has become a highly educated and intelligent young woman.” Born in Tuscumbia, Ala., Keller became ill with a fever at 19 months old, resulting in vision and hearing loss. She was a “spoiled, sturdy little animal,” wrote TIME, “hopelessly limited, and given to wild tantrums when cross.” This changed after Keller’s parents hired Anne Sullivan, a gifted young teacher, to show their daughter how to communicate. Thanks to Sullivan’s care and her student’s own persistence, Keller thrived, going on to graduate from Radcliffe College at age 24. Sullivan “first disciplined [Keller] into docility, then won her affection,” as TIME put it, a process dramatized in the Oscar-nominated 1962 film The Miracle Worker.

Because of the film’s focus, many people know more about Keller’s early years than they do about the remainder of her life. She is most often remembered for proving that people with disabilities can achieve success and live independently. But to frame her life as an up-by-the-bootstraps tale, in which sheer optimism and perseverance solve the personal challenge of disability, is to miss a large portion of what Keller fought for.

After college, Keller read Braille translations of works by Karl Marx, H.G. Wells and William Morris. She joined the Socialist party in 1909, and became an IWW member shortly thereafter, supporting strikes, walking picket lines, giving lecture tours and writing articles for publications like The Liberator. She noticed the close relationship between disability and poverty, and blamed capitalism and poor industrial conditions for both. As Keller told the New York Tribune in 1916, blindness was “often caused by the selfishness and greed of employers.”

In her writings and speeches, Keller called for revolution rather than reform. She had no patience for compromise, and argued that charitable aid did more to assuage the guilt of the prosperous than to improve the conditions of vulnerable people’s lives. Instead, Keller called for the dismantling of an economic order in which “the working class lives in want while the master class lives in luxury.”

Like many radicals of the 1910s and 1920s, Keller was concerned with multiple social-justice causes–she was a pacifist, a suffragist, a birth-control advocate, a supporter of the NAACP and a co-founder of the ACLU. But it was Keller’s socialist values that informed her position on other issues; she opposed World War I, for instance, on the grounds that it served capitalist interests, and helped create the ACLU as a way to protect striking workers from jail and deportation.

Despite these activities, Keller is more commonly remembered for the fundraising and advocacy work she did on behalf of the American Federation for the Blind, a largely apolitical organization. In fact, Keller’s leftist sympathies occasionally ruffled feathers with the conservative members of the American Federation. Her radical views also made her a target of FBI surveillance for most of her life. Still, Keller continued to support socialist and communist leaders, even in the midst of Cold War McCarthyism.

Keller has been given the Martin Luther King Jr. treatment: the more difficult and controversial aspects of her life have been neutralized in educational curricula, as well as in the public imagination. But during a time in which one in four disabled adults live in poverty in the United States, her perspectives on economic injustice remain significant. Inspirational messages on refrigerator magnets and postcards can temporarily lift someone’s mood, but throughout her life Keller wanted more than that. Rather than asking for hope, she demanded equality.

Get our History Newsletter. Put today's news in context and see highlights from the archives. Please enter a valid email address. Sign Up Now Check the box if you do not wish to receive promotional offers via email from TIME. You can unsubscribe at any time. By signing up you are agreeing to our Terms of Use and Privacy Policy . This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Thank you! For your security, we've sent a confirmation email to the address you entered. Click the link to confirm your subscription and begin receiving our newsletters. If you don't get the confirmation within 10 minutes, please check your spam folder.

Contact us at letters@time.com.