Wikipedia looks like it may soon become a victim of its own success: The free encyclopedia, with more than 4 million articles, is nearing completion.

That’s the argument in a new essay by military historian and Wikipedia editor Richard Jensen, at any rate, who points out that there’s an upper limit to just how many quality articles a single encyclopedia can host.

After an encyclopedia reaches 100,000 articles,” he writes in an article published in this month’s Journal of Military History, “the pool of good material shrinks. By the time one million articles are written, it must tax ingenuity to think of something new.”

Articles on the topics and subjects that really matter—from science, to art, to philosophy, to history—have already been written, edited, and refined down to near wiki-perfection. Sure, there will always be major events like Hurricane Sandy that demand new entries, but chronicling the slow drip of encyclopedia-worthy current events hardly compares to chronicling 10,000 years of human history.

Most of the major articles in Wikipedia were written in 2006-2007, and have gotten relatively little attention from editors since then,” Jensen wrote, noting that Wikipedia’s busiest year was more than a half-decade ago, in the summer of 2006.

Wikipedia’s been losing administrators faster than it can add them—the number of admins added to the ranks in September was the lowest on the site since 2005—and this may be part of the reason why. There’s just not much to do. That’s a problem. The World War II page may have been largely completed by 2007, but anyone can still go in and mess it up. The site’s administrators play an extremely important role: They keep out spam and vandalism. They’re the last line of defense against trolls.

Jensen proposed a solution to this: Give volunteer editors access to high-quality academic journals and invite them to conferences, so they can “bring the articles up to a more polished, professional standard.” But at a certain point Wikipedia will run out of articles to squeeze through these editorial standards, too. What then?

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