Hi, I don't read this list regularly, but hope you don't mind my jumping in.
It seems like this is the old historians' argument about whether history is determined by institutions or individuals. I would think both....
In reference to the sentence I quoted above, there was virtually nothing about 12th century Mongolian social structure that would have led anyone to think that a leader would arise who could unite fractious pastoral nomad clans and conquer most of the civilized world with them.
I hate to use the worn phrase paradigm shift, but it does cover the situation where someone arises who can transcend the existing social structure and create a new one. Not often, though, but sometimes.
I would imagine if someone had actually studied Genghiz's psychology, he likely would have seen a charismatic control freak who felt compelled to do something about steppe anarchy. Coupled with the weapons and tactics available to the nomads, that could have given our social psychologist a clue as to what might eventually happen.
I apologize if this takes the discussion off on a tangent -- the drawback of not keeping up with this maillist.
Eric Balkan
http://ibrakefortrees.wordpress.com