hat the standards by which the communities resolve their differences, e.g., "the principles of justice" must not come from only one of the cultures but must come "through an open and equal dialogue between them."
Balibar characterizes criticisms of multiculturalism as "differentialist racism", which he describes as a covert form of racism that does not purport ethnic superiority as much as it asserts stereotypes of perceived "incompatibility of life-styles and traditions".
While there is research that suggests that ethnic diversity increases chances of war, lower public goods provision and decreases democratization, there is also research that shows that ethnic diversity in itself is not detrimental to peace, public goods provision or democracy. Rather, it was found that promoting diversity actually helps in advancing disadvantaged students.
Wikimedia Foundation suggests that "diversity of perspectives is crucial to increasing the quality of the free knowledge resources that [their] movement provides.". Wikidata also suggests that "the world is complicated and there is no single [consensus—especially in a knowledge base that is supposed to serve many cultures."
Critics of multiculturalism often debate whether the multicultural ideal of benignly co-existing cultures that interrelate and influence one another, and yet remain distinct, is sustainable, paradoxical, or even desirable. It is argued that nation states, who would previously have been synonymous with a distinctive cultural identity of their own, lose out to enforced multiculturalism and that this ultimately erodes the host nations' distinct culture.
Harvard professor of political science Robert D. Putnam conducted a nearly decade-long study on how multiculturalism affects social trust. He surveyed 26,200 people in 40 American communities, finding that when the data were adjusted for class, income and other factors, the more racially diverse a community is, the greater the loss of trust. People in diverse communities "don’t trust the local mayor, they don’t trust the local paper, they don’t trust other people and they don’t trust institutions," writes Putnam. In the presence of such ethnic diversity, Putnam maintains that
[W]e hunker down. We act like turtles. The effect of diversity is worse than had been imagined. And it’s not just that we don’t trust people who are not like us. In diverse communities, we don’t trust people who do look like us.
Ethnologist Frank Salter writes:
Relatively homogeneous societies invest more in public goods, indicating a higher level of public altruism. For example, the degree of ethnic homogeneity correlates with the government's share of gross domestic product as well as the average wealth of citizens. Case studies of the United States, Africa and South-East Asia find that multi-ethnic societies are less charitable and less able to cooperate to develop public infrastructure. Moscow beggars receive more gifts from fellow ethnics than from other ethnies [sic]. A recent multi-city study of municipal spending on public goods in the United States found that ethnically or racially diverse cities spend a smaller portion of their budgets and less per capita on public services than do the more homogeneous cities.
- "Diverse peoples worldwide are mostly engaged in hating each other—that is, when they are not killing each other. A diverse, peaceful, or stable society is against most historical precedent."
A number of conservative historians used the religion of the Mexica, better known as the Aztecs as an example of what they see as the flaws of multiculturalism. The Australian historian Keith Windschuttle cited the accounts of his fellow Australian historian Inga Clendinnen of the festival of Ochpaniztli where to honor the Maize Lord a young woman was sacrificed by ripping out heart her so the crops might grow:
"Then, still in darkness, silence, and urgent haste, her body was flayed, and a naked priest, a 'very strong man, very powerful, very tall', struggled into the wet skin, with its slack breasts and pouched genitalia: a double nakednes