Thirty-five years before a German intellectual named Joseph Ratzinger ascended the throne of St. Peter and took the name Benedict XVI, a very different intellectual named Laurence Peter coined a rule which he named after himself: the Peter Principle.
Put simply, the Peter Principle says that people who are good at their jobs get promoted, and if they're good at their new jobs, they keep getting promoted -- until they get to a job they're not good at, where they stay.
As the troubled papacy of Benedict XVI limps to a close, it appears very possible that the rule describes Ratzinger's eight years at the head of the Roman Catholic Church.
Call it the Throne of Peter Principle.
"He was just the wrong man for the wrong time, which is nothing to do with him as a person," said Christopher M. Bellitto, author of the book "101 Questions and Answers on Popes and the Papacy."
"He was not a manager. He was a lousy administrator," said Bellettino, chair of the history department at Kean University in Union, New Jersey. "Sometimes someone is a great mayor and a lousy governor and I think that's probably what happened with Benedict."
The Vatican was battered by one highly public crisis after another while Benedict was pope.
The sexual abuse scandal that first flared in the United States when John Paul II was pope caught flame under Benedict, burning across the country and into Europe.
Just this month, two top American cardinals, Roger Mahoney of Los Angeles and Timothy Dolan of New York, were called on to give legal testimony over lawsuits related to abuse of children, and the leader of Scotland's Catholic Church, Cardinal Keith O'Brien, resigned after allegations he had acted improperly toward four men studying for the priesthood decades ago.
The sexual abuse crisis wasn't the only problem Benedict faced.
His own butler leaked private papers from his apartment and gave them to a journalist. The Vatican Bank has tried -- and failed -- to achieve international standards to prevent money laundering.
Pope Benedict welcomed back into the fold Richard Williamson, an excommunicated bishop who, it turned out, doubted the scale of the Holocaust. The Vatican was forced to admit it hadn't known of the bishop's views on Auschwitz before the lifting of the ban -- although an interview where Williamson outlined them was posted on YouTube.
Just a year and a half after Benedict became pope, he infuriated many Muslims by quoting a medieval Byzantine emperor who said: "Show me just what Mohammed brought that was new, and there you will find things only evil and inhuman, such as his command to spread by the sword the faith he preached."
The Vatican was quick to say that it was the emperor's view that Islam was evil, not the pope's, but the gaffe is emblematic of the problem with Benedict, Bellettino said.
"This was a tone-deaf papacy. This has not been a savvy papacy," he said.
The Rev. Thomas Reese, author of "Inside the Vatican," said Benedict's greatest strength was that he was an intellectual and a teacher -- but that was also his greatest weakness.
"The last two conclaves, what they did was they elected the smartest man in the room," he said: John Paul II and Benedict XVI.
"Both were intellectuals, both were scholars, academics," Reese said.
"Maybe it's time to not elect the smartest man in the room, but to elect someone smart who will listen to all the other smart people in the room, and not just in the room but in the church -- someone who brings people together, who builds a team," Reese said.
But Benedict has his defenders.
Thomas Peters, a Catholic activist who blogs at AmericanPapist, said there are powerful forces at work when cardinals gather to elect a pontiff.
"We believe the Holy Spirit guides the choice of the pope," he said.
And he argued that the idea of a Vatican in disarray under Benedict XVI was false.
"I think there's a meme out that the church is a dysfunctional bureaucracy," he said, then rejected it: "It does make the trains run out time."
Benedict has appointed able administrators who are making the Vatican machinery function more swiftly, Peters said, describing an "American renaissance of administrator cardinals and archbishops."