It's not unusual for the words of influencers to gain popularity. But the influential philosopher Henry David Thoreau was born more than 200 years ago -- and now a term he's credited with introducing, "brain rot," is the Oxford University Press's word or phrase of 2024.

Brain rot was selected by thousands of online voters. But that doesn't necessarily mean they're well-versed in Thoreau's work, particularly his 1854 book Walden, or Life in the Woods, where he wrote about "brain-rot." It was the first recorded use of the term, according to Oxford University Press.

Today, brain rot reflects a worry that consuming the internet's endless waves of memes and video clips, especially on social media, might numb one's noggin.

In Walden, Thoreau used the term as he railed against oversimplification.

He asked, "Why level downward to our dullest perception always, and praise that as common sense?"

Thoreau ended that paragraph with another question: "While England endeavors to cure the potato-rot, will not any endeavor to cure the brain-rot, which prevails so much more widely and fatally?"

So, is the new rot the same as the old rot?

Oxford's language experts say brain rot gained traction on platforms such as TikTok this year, thanks to Gen Z and Gen Alpha. Frequency of the term's use grew by 230% from 2023 to 2024, according to the publisher's monitoring tools.

At first glance, the connection to Thoreau may seem odd, but consider this: when Thoreau relocated to his cabin near Walden Pond to get back to basics in 1845, he was 27 years old -- the same age as the oldest Gen Z members.

To better get a sense of how Thoreau saw brain rot in the 1800s, NPR contacted Cristin Ellis, an authority on Thoreau who teaches literature at the University of Mississippi.

"For Thoreau, 'brain-rot describes what happens to our minds and spirits when we suppress our innate instincts for curiosity and wonder," Ellis says, "and instead resign ourselves to the unreflective habits we observe all around us -- habits of fitting in, getting by, chasing profits, chatting about the latest news."

In today's usage, brain rot is seen as a bad thing, sort of a cautionary term for what might happen to us if we get too distracted.

"I think the definitions are related but Thoreau's sense of brain rot is way more extreme," Ellis says.

"It's not just TikTok dance crazes but virtually our entire 24/7 media culture -- including the "serious" news of newspapers -- that Thoreau would accuse of trivializing our minds," she adds.

"Thoreau really values direct experience over our habits of consuming other peoples' ideas at second hand," Ellis says. "He wants us to go outside to feel and think something for ourselves; he wants us to get to know the places where we actually live."

Popularity hints at online anxieties

Words of the year often mark shifts in thought and concerns about where society is heading -- see "climate emergency" from 2019 and "vax" from 2021.

Compared to Oxford's recent words of the year, brain rot suggests a reflective mood, after the more indulgent vibes of "goblin mode" in 2022 and "rizz" in 2023.

Casper Grathwohl, president of Oxford Languages, said in a news release sent to NPR that he finds it fascinating that "brain rot" is being embraced by younger people. "It feels like a rightful next chapter in the cultural conversation about humanity and technology," he said.

"There's an anxiety coming through about striking the right balance between the online world and losing touch with the real world," Oxford Languages product director Katherine Martin said. "I think it's great that young people also use this term to refer to the type of language used by people who overindulge in online content, which is wonderfully recursive and self-referential."

"Brain rot" beat out five other contenders: demure; dynamic pricing; romantasy; slop; and lore.

Demure became a sensation -- and is Dictionary.com's word of 2024 -- largely thanks to online content creator Jools Lebron's catchphrase, "very demure, very mindful."

Back to Thoreau -- how might he have seen our culture?

"I think he might actually see us as in a more or less similar predicament as the society he lived in," Ellis says. "He had no time for the complaint that societies in the past were somehow better, nobler, smarter than the present day."

Shortly after Thoreau raises the specter of "brain rot" in Walden, he warns readers against being distracted by questions about the deterioration of society's collective intellect. He also returns to a central theme: people should aim for their own personal achievements.

"His point here is that whether or not things are worse now than they were (and in general he's skeptical of that kind of nostalgia), our task at all times is the same: to try our hardest to commit ourselves to the things that matter most in our brief and miraculous lives," Ellis says.

"Devote your attention to what you know, in your heart of heart, really matters: meaning, beauty, love, wonder, and gratitude for this earth."

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