A telling proof of the argument Pope Benedict XVI made at Regensburg University last week is that prominent Muslim critics claimed to embrace his basic point even as they strove to disprove the words of the 14th century Byzantine emperor the pope quoted.
The pope's point was not to critique Islam, but to make an observation about religious truth: It is consistent with reason.
The initial part of Benedict's long quotation from Manuel II Paleologus received much attention, but the rest too little.
"Show me just what Muhammad 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 pope quoted Paleologus.
But then the pope said: "The emperor, after having expressed himself so forcefully, goes on to explain in detail the reasons why spreading the faith through violence is something unreasonable. Violence is incompatible with the nature of God and the nature of the soul. 'God,' he says, 'is not pleased by blood -- and not acting reasonably is contrary to God's nature. Faith is born of the soul, not the body. Whoever would lead someone to faith needs the ability to speak well and to reason properly, without violence and threats. ... To convince a reasonable soul, one does not need a strong arm, or weapons of any kind, or any other means of threatening a person with death ... ."
Having presented the emperor's analysis, the pope asks: "Is the conviction that acting unreasonably contradicts God's nature merely a Greek idea, or is it always and intrinsically true?" The pope's answer: Always true.
Now, some radical Muslims rebutted the pope's quotation of Paleologus with dramatic irony. The Mujahedeen Shura Council, an organization that includes al-Qaida in Iraq, contested the notion that Islam was spread by sword by vowing to spread Islam by sword.
"We will break up the cross, spill the liquor and impose head tax, then the only thing acceptable is a conversion (to Islam) or (killed by) the sword," it said.
Some Muslim governments, however, accepted the premise that spreading faith by violence is unreasonable and contrary to God, while insisting that Islam does not violate this principle.
Before describing the pope's words as "the latest link" in "the chain of this American-Zionist conspiracy," for example, Iran's supreme leader, Ayatollah Khamenei was indignant anyone should deem his Islamic vision unreasonable. "Accusing Islam of being disconnected from reason and of being uncaring about reason is as unjust as denying a blatant fact, denying the sun's benefits, denying the sun's light," he said.
"Jihad in Islam is not for imposition of beliefs, it is for combating those who enslave people."