By Zusha Elinson

BERKELEY, Calif. -- In the Bay Area, a place teeming with brainy computer scientists, an intellectual movement called "the rationalists" debates existential issues, such as preventing artificial intelligence from destroying humanity.

Yet even in a community that prides itself on welcoming anyone, a new arrival from Alaska stood out, a programmer named Jack LaSota. Intense, robed in black, adopting the name "Ziz" after a comic-series villain and espousing violence against meat eaters, LaSota so unsettled the rationalists that one organization expelled her from official events.

The rationalists' suspicions proved prescient. The Zizians, a splinter group of militant vegans led by LaSota, has been linked to six deaths, including the slayings of an elderly Pennsylvania couple, a California landlord and a U.S. Border Patrol agent in Vermont.

Rationalists fear for their safety. The prominent Berkeley-based Center for Applied Rationality, where LaSota once attended meetups, has increased security and standards of behavior at events.

"Ziz clearly had a lot of unique and extreme ideas before encountering the rationalist community," said Zvi Mowshowitz, a center board member. "A lot of these ideas clearly didn't come from us."

Discussions of the Zizians course through rationalist forums, as adherents wonder whether their nerdy do-gooder subculture inadvertently seeded a violent faction. The soul-searching echoes the reactions to Sam Bankman-Fried's fraud conviction -- the cryptocurrency billionaire followed effective altruism, which uses reason to maximize human welfare.

This past Sunday, Maryland police arrested LaSota, 34 years old, on trespassing, obstruction and gun charges alongside two friends. She denied wrongdoing and hasn't been charged in any of the killings.

Daniel Blank, 26, a shy computer whiz arrested with LaSota, hasn't spoken with his parents since joining the Zizians about two years ago, his father said.

"I think he's programmed by the cult," said Alexander Blank.

'Many smart people'

Eliezer Yudkowsky, a self-taught philosopher known for "Harry Potter and the Methods of Rationality," leads the rationalist movement. Two Berkeley institutions anchor it: the Center for Applied Rationality, which runs workshops and sponsors the popular "Less Wrong" online forum; and the Machine Intelligence Research Institute.

The community explores "how do we make better decisions? How do we know what's true?" said Mowshowitz. Rationalists apply logic and probability in vigorous debates, often inspired by utilitarian, libertarian and rationalist thinkers.

The movement attracts brilliant, often self-described outsiders -- atheists, autistic or transgender individuals -- and encourages consideration of all concepts on merit, including scenarios like a robot apocalypse.

"This openness to strange ideas and unconventional lifestyles has allowed for many smart people to build innovative and inspiring communities that couldn't exist elsewhere," said Ben Pace, co-founder of the current iteration of the Less Wrong forum.

But that had downsides. The open door could give those unwelcome elsewhere -- for good reasons -- "a space to behave badly together and form more unhealthy communities," he said. "Someone like LaSota would not be welcome here today."

'Dark side'

Rationalists have drawn luminaries. The venture capitalist Peter Thiel funded the work of the Machine Intelligence Research Institute early on. The former OpenAI researcher Paul Christiano, now in leadership at the federal government's AI Safety Institute, frequently posted on Less Wrong.

Jack LaSota fit the archetype. A magna cum laude computer scientist from the University of Alaska, Fairbanks, she migrated to Bay Area tech jobs. Tall with flowing golden locks, she displayed the movement's quirky wit, once joking on Facebook about repealing the first law of thermodynamics.

She attended Center for Applied Rationality workshops, and lauded Yudkowsky's lecture on finding startup ideas: "Look for a way the world was broken," she blogged.

She came out as transgender, embraced veganism, and gathered peers to live on a tugboat near Half Moon Bay.

But as "Ziz," LaSota's ideas appeared increasingly violent to other rationalists, including allegedly calling for "Nuremberg trials" for meat eaters. She cultivated followers -- the "Zizians" -- and chronicled her "journey to the dark side" as she grew disillusioned with the movement. Some at the Center for Applied Rationality became "creeped out, " one center official wrote on Facebook.

Tensions peaked in 2019 when the center was dismissive of the Zizians' supposed research into putting half of the brain to sleep, according to other members. They recall the Zizians protesting a center reunion, wearing Guy Fawkes masks and accusing leaders of corruption and transphobia.

LaSota's orbit included Daniel Blank. He long struggled to make friends, his father said. In Berkeley's rationalist circles, he finally found them. Blank told his father he liked the meetups because he wanted to do good in the world but didn't know how.

His father recalled a child so gentle he wouldn't pull on the family dog's leash. Despite showing symptoms of Asperger's syndrome, he double-majored in bioengineering and computer science at the University of California, Berkeley, before landing tech jobs.

But about two years ago, Blank moved across the country and severed contact. His worried family filed a missing-person's report.

Faked death

By August 2022, the Zizians saga appeared over when the Coast Guard received word that LaSota had gone overboard in San Francisco Bay. An Alaska newspaper even published an obituary: "Loving adventure, friends and family, music, blueberries, biking, computer games and animals, you are missed."

But LaSota hadn't drowned. That November, police spotted her at the Vallejo, Calif., scene where they said three Zizians attacked their elderly landlord, Curtis Lind, with knives and a sword. Lind fired a handgun, killing one. A prosecutor's email to LaSota's attorney confirmed: "Lasota was on the scene, alive and well."

The trail darkened weeks later with the execution-style slayings of Richard Zajko, 72, and Rita Zajko, 69, in Pennsylvania. Police discovered their daughter, Michelle, with LaSota and Blank at a nearby hotel.

LaSota was arrested for alleged obstruction, then vanished after making bail. Daniel McGarrigle, LaSota's attorney in the Pennsylvania case, disputed the charges.

"Whatever you may think of the person, whatever you may think of the person's identity politics or ideas or associations, you can't turn non crimes into crimes because you don't like those other things," he said.

Anxiety rose in Berkeley. A Less Wrong poster warned in February 2023 that some rationalists "are concerned about risks of physical violence from Ziz and some of her associates."

True to form, the community dissected the events. Oliver Habryka, chief executive of Lightcone Infrastructure, which runs Less Wrong, used modeling and bullet points to analyze why "rationalists sometimes turn crazy."

Online debate ensued -- and backlash, since Habryka hadn't used LaSota's chosen name.

"Ziz got several friends of mine killed. So i dont exactly have a high opinion of her," one commenter wrote. "But I have never heard of Ziz referring to themselves as LaSota. Its honestly toxic not to use people's preferred names."

In reflection, Pace wonders if the Zizians were influenced by other schools of thought, such as radical "strains of social justice communities."

"Given her apparent willingness to escalate to grievous levels of violence, and her efforts to persuade vulnerable people to join her...I wish she had been banned far earlier," he said.

January manhunt

Over three days last month, Lind, the Vallejo landlord, was stabbed to death as he was set to testify against the Zizians accused in the 2022 sword attack, and Border Patrol agent David Maland died in a shooting in a Vermont traffic stop. The bicoastal killings seemed unconnected.

Then authorities revealed the suspects: Maximilian Snyder, 22, an Oxford-trained data scientist charged in Vallejo; and Teresa Youngblut, 21, a computer scientist charged in Vermont. The pair, who filed for a marriage license, shared vegan beliefs, interest in AI and roots at the same elite Seattle-area prep school, according to their social-media posts and a letter written by Snyder.

Federal prosecutors hinted at another connection in a January court filing, saying Youngblut knew and maintained contact with someone who had been detained in a Pennsylvania homicide investigation and was a person of interest in a Vallejo case.

While authorities didn't name the person, Berkeley rationalists suspected another Zizian.

The manhunt ended on a Maryland country road this past week when LaSota, Blank and Michelle Zajko, armed and wearing black, sought to camp on private land. A suspicious resident called police.

On Tuesday, a judge ordered LaSota held without bail. At the hearing, LaSota said she had done nothing wrong and reportedly complained the jail wasn't offering vegan food. Her hunger, she said, was making her delirious.

Write to Zusha Elinson at zusha.elinson@wsj.com

(END) Dow Jones Newswires

February 22, 2025 05:30 ET (10:30 GMT)

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