But the detail that leaves the largest impression is Zuckerberg’s personal relationship with the truth. Given his lofty position at Facebook, “it is difficult for him to get genuine, unexpurgated feedback” from employees, Osnos writes. What’s more, the CEO’s “unwillingness to heed warnings,” his college hacker mentality long hardened, has made any efforts to “puncture his own bubble,” in Osnos’ words, less than, well, truthful.

It’s a funny turn of phrase, come to think of it. Zuckerberg has long worked in a glass rectangle—a fishbowl of a sort—at Facebook’s Menlo Park, Calif. headquarters. The gesture is meant to convey the CEO’s radical transparency, but to me, it has long communicated the opposite. The bubble boy behind “Move fast and break things” rarely wanted to shatter his own barrier in pursuit of truth, however disagreeable. Somewhere along the way to becoming a Fortune 500 media executive, Osnos notes, Zuckerberg began to see virtue in rejecting complaints. “There’s always someone who wants to slow you down,” Zuckerberg said in a commencement address at Harvard last year.

Here’s the thing about the facts, though: they are stabilizing. Though Zuckerberg, a Roman history buff, has chosen his approach—“Like Augustus, he is at peace with his trade-offs. Between speech and truth, he chose speech,” Osnos writes—he should be wise to remember how that story ends: with Nero, a great fire, and a fabled fiddle.

This essay first appeared in Data Sheet, Fortune’s daily download on the business of technology. Subscribe.