* High-level creativity needs a coherent setting and tradition to give it materials and possibilities. That’s why there is no Shakespeare of pidgin. As Sailer points out, ethnic cuisines developed in monocultural settings.
* In multicultural society the only principles of order are arm’s length contract and top-down management. There’s not enough of a network of ties and common understandings for anything else to work. Neither allows for much creativity, because they’re too simple and single-minded.
* Then there’s the obvious point, that if you have a multicultural society that has to pretend to be free, equal and democratic you have to control thought and expression in boring ways to keep the whole house of cards from collapsing. “Celebrating diversity” means refusal to deal with any important issue in an interesting way, because you might end up saying that something is better than something else.
* Don’t evolutionary biologists talk about the importance of isolated niche situations for speciation? Whatever its status in biology, the reasoning suggests that cosmopolitan societies would be uncreative.