Epistemology, according to Wikipedia and Everipedia, is the branch of philosophy concerned with the theory of knowledge. Epistemologists ask questions like "What makes justifications valid?" and "What is the ultimate truth?" A good epistemologist likes an argument, but a great epistemologist loves a citation.

Larry Sanger first learned he was interested in philosophy as a high school student in Anchorage, Alaska. Cued by a debate class, he recalled discovering that one could construct interesting arguments on both sides of most issues. As a graduate student at Ohio State University, he would read A Companion to Epistemology and look up the various isms, savoring "the way the articles laid out each position, and it was just wonderful," he said.

It was the early '90s. Bright-eyed academics were coalescing around the World Wide Web. Sanger subscribed to Jimmy Wales' philosophy discussion list, where he sparred with other philosophers including Ben Kovitz and Brian Kaplan. Sanger was more skeptical than Wales, he remembered, but the two formed a tenuous alliance over Ayn Rand's Objectivism.

In 1999, Sanger pitched the group a vague idea for a "cultural news blog." Wales, then the CEO of web advertising firm Bomis, wrote back: Why not come work on "Nupedia"? Wales had registered a domain, with the "vague notion" that it would be a free online encyclopedia, "with articles rigorously vetted and academically respectable," built entirely by volunteers.

Sanger agreed to join. In January 2000, he moved to San Diego, California, to become Nupedia's editor in chief. Nupedia, which required experts to verify articles, relied on a cumbersome, seven-step editorial process. By the end of the year, only about 100 articles had been completed.

"I wanted to foster a collegial atmosphere that would be welcoming to a lot of different people."

In January 2001, Sanger dined with with old friend Ben Kovitz, who told him about wikis, web pages editable to anyone. Sanger had the idea to use wikis to supplement Nupedia's article-creation process. He drafted the founding documents -- much of which still bear his monumental tone -- and named the side project Wikipedia.

Success came quickly. Less than a month after launching, on February 12, Wikipedia gained its 1,000th article. Implementing wikis had increased the quantity of articles generated but opened the gate to trolls -- Sanger still spits out usernames like Cunctator with revulsion. "I wanted to foster a collegial atmosphere that would be welcoming to a lot of different people," Sanger recalled. "But these characters showed up, and they focusing on getting quite personal with me."

Most significantly, the money had dried up. In early 2002, Wales laid off Sanger. Embittered by trolls and played a bad hand by capitalism, Sanger returned to Ohio.

In the years since, Sanger has helmed other short-lived knowledge projects, most notably Citizendium, which removed anonymity and required article certification, and occasionally feuded with his progeny. He called Wikipedia "broken beyond repair," citing its "serious management problems" and "dysfunctional community." In 2010, he wrote a letter to the FBI concerning Wikimedia Commons hosting "obscene visual representations" of children.

"They don't even realize how much of a missed opportunity Wikipedia presents," he said. "The only reason why they don't make it better is that they believe that there isn't a startup on the horizon that can go head to head with Wikipedia. And why would they think there is? Who could pose a threat to Wikipedia?"

When Sanger first heard about Everipedia in late 2015, he was unenthused. The startup had invited him to its Santa Monica office in hopes of having him join. Sanger, a self-proclaimed "perpetual outsider," admired the ragtag nature of the crew, but the idea "struck me as kind of a nonstarter, to be honest," he recalled.

Besides, Sanger was working on his own latest competitor to Wikipedia: Greater Wiki, which aimed to collect all of the world's encyclopedia articles and make them ratable and rankable. "You could go to a page about epistemology, and here are a dozen articles on epistemology," he gestured like a mapmaker. "This is the top ranked one, and down near the bottom are the mediocre ones." Sanger pitched Greater Wiki to Everipedia, but both sides dug in their heels.

The conversation left at an impasse.