As I see the entire Islamic world going rather mad over Pope Benedict’s largely, but not entirely, inoffensive speech (incidentally, I do not hear the laments of a lot of Lutherans berating him for laying charges of de-Hellenisation at their door), I see a number of other defenses of the speech that claim Pope Benedict did not endorse Manuel II’s view.  So did he endorse Manuel II’s views?  Well, yes and no. 

It seems very clear that he endorsed and took as his basic theme Manuel’s statement:  “Not to act reasonably (with logos) is contrary to the nature of God.”  In other words, he took what was best from the speech and, if one wants to see this as an ecumenical speech, personally left aside the more combative bits about Muhammad introducing nothing but evil and inhuman things.  (I can see how that might be irritating, but then I would ask what exactly Muhammad did bring that was not either of these things.)  He did not state his agreement with the whole of Manuel’s dialogue, but merely called it “interesting.”  He did not explicitly reiterate the charges against Muhammad and Islam, but it seems clear that if he regarded the Persian interlocutor’s view as representative of Islamic theology (and he would have strong reasons to do so from within Islamic history and theology–the outcome of the debate in the 9th century between determinists and ‘libertarians’ already points us towards this conclusion without reference to Ibn Hazn) he clearly recounted the episode as a way of remarking on an important difference between the rival conceptions of God.  The comparison clearly works to the disadvantage of Islam, which is not Pope Benedict’s fault, but the fault of Islam’s own faulty conception of God.  Logos here carries the same multivalent sense that it has always carried for Christian apologists, confessing that wherever there is reason, there is the Word, Who is Christ.  Again, this draws a contrast with Islam, in which the Qur’an is the eternal word of Allah.  Once again, this is not a flattering comparison for Islam. 

By not making a text itself into something eternal, but reserving eternity to God the Word, Christian exegesis was able to make use of words (logoi) and Christian rhetoric was able to make use of speech (logos) in flexible and dynamic ways that permitted the interaction with classical texts and classical rhetoric on the assumption that anything reasonable, true or beautiful in them was a mark of the divinely created order, created through the Word.  Permitting this application of reason to Scripture then permitted a wide range of reasoning about doctrine (within reason, of course) that necessitated and generated an interest in classical philosophy that was at the mainstream of church life, while the same philosophy could only be embraced deeply by Muslim scholars if they were willing to court condemnation.  I have seen it said that classic Islamic scholars made significant use of Greek technical treatises in mathematics, astronomy and other natural sciences, but tended to avoid all those aspects of philosophy that touched on human affairs, assuming that there was nothing needful or edifying in them and assuming that Allah had already delivered the complete answer through revelation.  Where Athens was meaningful and important (because philosophical inquiry was itself seen as a fruit of God the Word), but subordinate to Jerusalem, Athens was merely occasionally useful to Mecca and ultimately of little significance.  Between the spirit of inquiry urged on by the life-creating Word and this frequently technical application of reason there is a wide chasm.  

Fundamentally, a religion that expanded through conquest had less need to reconcile the heritage of Athens with revelation, as there was no need for persuasion and thus no audience deeply committed to the heritage of Athens to be convinced in the first place.  But in the Christian tradition once the link was definitively made between the pursuits of reason and the Word of God, a certain degree of inquiry itself became a religious calling.  Thus what became commonplace and normative in Christianity was an outlier or a flash in the pan in Islam.  Against this Muslims may riot all their like, but it is the legacy of their religion and their history.