When Luigi Mangione was arrested in the killing of the chief executive of UnitedHealthcare, he was hailed in some corners of the internet as an anti-capitalist folk hero.

In a document said to be a “manifesto” found with Mangione, published online by journalist Ken Klippenstein, the 26-year-old former data engineer condemned UnitedHealthcare for abusing “our country for immense profit.”

“Frankly, these parasites simply had it coming,” Mangione wrote. “A reminder: the US has the #1 most expensive healthcare system in the world, yet we rank roughly #42 in life expectancy.”

But Mangione was not a straightforward, left-leaning Robin Hood figure avenging what he sees as the brutality of the U.S. healthcare system or, as one right-wing critic alleged, “just another leftist nut job.” The political ideology he articulated online — on social media platforms from X and Reddit to Goodreads — defied neat left-right binaries and showed a young man steeped in a hodgepodge of online Silicon Valley philosophy and heterodox ideas.

Mangione’s internet postings, along with accounts from people he knew and talked to online, offer a complex view. Mangione’s last post on X was in June, nearly six months before he allegedly traveled to Manhattan to kill, and he appeared to disconnect from his family and friends around the same time. But his digital footprint offers a glimpse into his ideological journey, documenting some of his deepest hopes and anxieties about the future of technology and humanity.

The former valedictorian of an elite Baltimore prep school and Ivy League graduate shared posts on social media from an eclectic stream of populists, entrepreneurs, neuroscientists, centrists and disruptors. On X, he followed comedian and podcaster Joe Rogan; President-elect Donald Trump’s nominee for health secretary, Robert F. Kennedy Jr.; liberal columnist Ezra Klein; and democratic socialist Rep. Alexandria Ocasio-Cortez of New York.

On a now-private Goodreads account that authorities reportedly identified as belonging to Mangione, he included a biography of tech billionaire and GOP megadonor Elon Musk — now a close Trump advisor — in his favorites list and rated Republican Vice President-elect J.D. Vance’s memoir “Hillbilly Elegy” three out of five stars.

A computer science major with an interest in rationalism, self-improvement and effective altruism — a philosophical movement that uses evidence and reason to help others — Mangione enthused about technological innovation. But he also worried about how corporations and ordinary people used tech, sharing a stream of posts on smartphones’ effect on mental health, the downside of Netflix and Doordash, and an AI chatbot’s threats to carry out revenge.

Mangione appeared skeptical of some of the core tenets of left-leaning “identity politics.”

Two years ago, he shared a post from British Indian writer Gurwinder Bhogal challenging the idea that asking “Where are you from?” is impolite: “If wokeism teaches minorities to be traumatized even by friendly gestures, it cannot claim to bridge divides.” In April, Mangione retweeted a blogger who complained that modern-day atheists “disprove[d] God” only to end up “worshipping at the DEI shrine” and “using made-up pronouns like religious mantras.”

Some on the left are now dubbing Mangione right-wing, but they do not seem to agree on whether he is a “center-right biohacking Thiel-loving tech bro” or “another far right MAGA Trumper Terrorist.”

Bhogal, who chatted and emailed with Mangione online after the American became a founding member of his Substack, said Mangione was neither.

“He was left-wing on some things and right-wing on others,” Bhogal wrote in an email. “He was pro-equality of opportunity, but … he opposed wokeism because he didn’t believe it was an effective way to help minorities.”

Bhogal said Mangione first reached out to him in April while on a trip in Asia. Mangione asked him about a 2023 article Bhogal wrote exploring the rise of the NPC, or Non-Player Character, a term referring to video game characters that some online subcultures now use to describe humans who behave in predictable, scripted ways.

The article resonated with Mangione, Bhogal said, probably because he felt he did not fit into a political tribe. Bhogal described Mangione as curious and well-read, with “mostly quite tame” intellectual interests in “brain rot, indoctrination, declining birth-rates, gamification and corporate greed.”

On X, Mangione praised conservative commentator Tucker Carlson as “spot on” in recognizing that “modern architecture kills the spirit” and shared a video of a talk by venture capitalist and GOP megadonor Peter Thiel on why people with Asperger’s syndrome excel in tech.

On Goodreads, he gave “Industrial Society and Its Future” by the late Theodore Kaczynski, also known as the Unabomber, a four-star review. Kaczynski was “rightfully imprisoned,” he wrote, but he also noted: “it’s simply impossible to ignore how prescient many of his predictions about modern society turned out.”

At the end of his review, Mangione quoted a random Reddit user, Bosspotatoness: “These companies don’t care about you, or your kids, or your grandkids. They have zero qualms about burning down the planet for a buck, so why should we have any qualms about burning them down to survive?”

According to Bhogal, Mangione seemed disillusioned with status quo politics, but he appeared to dislike Trump.

“He believed corporate greed for short-term profits was causing tech companies to saturate society with mind-rotting entertainment,” Bhogal wrote. “He asked me how to maximize agency in a world constantly trying to deprive us of it.”

Those who got to know Mangione in 2022 when he lived at the Surfbreak co-working community near Honolulu described him as a normal, affable guy.

“He did not seem hardcore in any direction,” said Josiah Ryan, a spokesperson for Surfbreak owner and founder R.J. Martin. “No one really knows what his political views were. He seemed balanced, young and curious, without a noticeable ideology.”

Though Mangione came off as anti-capitalist and anti-corporate in his manifesto, Brian Levin, founder of the Center for the Study of Hate and Extremism and professor emeritus of criminal injustice at California State San Bernardino, said that didn’t necessarily make him hard-left. Increasingly, Levin noted, anti-corporate and anti-institutional subcultures operate across the ideological spectrum.

“We’re seeing a diversification of these types of extremism, as well as an a la carte construction of idiosyncratic beliefs that are sometimes hooked into an ideology,” Levin said, noting that two years ago, a mass shooter who killed eight people at a mall in Allen, Texas, was a Latino with a Nazi tattoo. “Let’s see where the defendant falls.”

Mary Beth Altier, a clinical professor at New York University’s Center for Global Affairs who studies political violence and behavior, said it was becoming more common for political violence to be largely motivated by a single issue, in this case the healthcare industry.

“They’re not necessarily fitting into a larger group or ideology,” she said, “but rather have a personal grievance with a particular issue.”

Online, some pundits and extremism experts have suggested that Mangione expressed views associated with “the gray tribe”, a term coined a decade ago by Bay Area psychiatrist and blogger Scott Alexander, to refer to an online collective of rationalists, online tech enthusiasts, atheists and free thinkers who fall outside conventional left- or right-wing tribal thinking.

“Increasingly looks like we’ve got our first grey tribe shooter,” journalist and extremism expert Robert Evans posted on X the day Mangione was charged. “Boy howdy is the media not ready for that.”

As Alexander described it, the gray tribe espouses “libertarian political beliefs, Dawkins-style atheism, vague annoyance that the question of gay rights even comes up, eating paleo, drinking Soylent, calling in rides on Uber, reading lots of blogs, calling American football ‘sportsball,’ getting conspicuously upset about the War on Drugs and the NSA…”

As obscure as Mangione’s views might seem to Americans who do not dwell in the same online spaces, Evans wrote on his Substack that “his interest in Gray Tribe-adjacent thinkers and self-help books written by productivity hackers … is incredibly common among young men.”

Other observers of internet subcultures suggested Mangione was a “new tech centrist” or “TPOT adjacent,” an acronym for This Part of Twitter, another loose offshoot of Silicon Valley “post-rationalism” that developed online during the COVID-19 lockdown and focuses on ideas, technology, spirituality and conspiracy theories.

Some joked about the difficulty of attributing motivation to Mangione in an era of increasingly in-the-weeds online subcultures.

“Tried explaining that the shooter wasn’t a far left radical but actually a right wing tpot adjacent ted k reading lindyman following, rfk pilled upenn grad,” one poster wrote on X. “Got kicked out of the family group chat.”

Typically, Levin said, those who engage in public acts of symbolic violence are motivated by one, or a combination of, three factors: ideology, which could be religious or political; a psychological condition or mental instability; a sense of personal benefit or revenge.

“The bottom line here is this is someone who experienced a grievance, and that grievance resonated,” Levin said of Mangione. “The combination of grievance, idiosyncrasies, personal psychological distress, withdrawal from support systems and the glorification of violence that exists generally in our society will have a special effect on individuals who feel an unjust grievance or who feel the system doesn’t work.”

Mangione’s last post on X appears to be June 10. By November, his mother filed a missing-person report for her son in San Francisco.

A fitness buff, he had suffered health setbacks. The top banner of his X profile, next to a photo of him posing shirtless and smiling atop a mountain, was an image of an X-ray showing four screws in a spine, a sign that he had gone through lumbar spinal fusion surgery.

Posts from a since-deleted Reddit account, with details matching Mangione’s biographical details, showed that Mangione suffered from chronic back pain resulting from spondylolisthesis — a condition in which a vertebra in the spine, usually in the lower back, slips out of place. Mangione wrote that his condition was exacerbated by a surfing accident.

“My back and hips locked up after the accident,” he wrote in July 2023. “I’m terrified of the implications.”

Mangione is pictured in a holding cell after being taken into custody Monday in Altoona, Pa.

(Altoona Police Department / Getty Images)

Mangione wrote that he underwent spinal surgery weeks later, which appeared to have improved his symptoms.

When Bhogal chatted with Mangione via video for two hours in May, he did not get the impression that he was in pain or on painkillers. “He seemed lucid, relaxed, and cheerful,” Bhogal wrote.

But Bhogal said Mangione may have felt isolated. He complained the people around him were on a “different wavelength” and seemed eager to join a community of like-minded people. He urged Bhogal to schedule group video calls to discuss rationalism, Stoicism and effective altruism.

That never happened.

The last time Bhogal heard from Mangione was June 10, when he received a message in which Mangione asked him how to curate his social media feeds. Bhogal forgot to get back to him.

A part of him wonders, now, if he could have averted the apparent outcome if he had replied.