Are there any legitimate arguments against homogeneity?

A really interesting question actually that unfortunately I think will receive a lot negative responses.

Biologically speaking, there are good reasons to ensure a wide gene pool. For this purpose, having a society with people from all over world will mean the populous is comparatively stable and less likely to get wiped out by a certain disease for example.

You have listed a number of problems with having a diverse and multicultural society. I would like to ask you if you think this is a necessary outcome of a multicultural society. That is, whether it is possible to have a multicultural society without such issues? Because if so, then it simply that our society has not yet developed sufficiently to deal with such problems. Are you aware of any multicultural societies that have been flourishing?

Now, of course to promote multiculturalism I still need to present arguments for why it might be useful. It is important not to think of diversity as being good simply because it is diverse.
One possible argument is simply a question of efficiency. Each culture will have its own benefits, and by mingling we can share ideas, (including food) by taking the best from each. Further, this diversity can add more variety and interest into one's life and as we make life choices we may be more likely to find something we like in a more diverse society. Finally, there are reasons to think that a diverse society is more likely to be accepting of new ideas, which links to the efficiency argument but can also be important morally (in theory) in terms of tolerance.

Or any good arguments in favour of multiculturalism/diversity?

It seems to me to be obvious that a society where people share the same ethnic heritage, same culture etc, is inherently stronger and more cohesive. Look at the BLM protests in the UK recently for example - police brutality isn't even a thing in the UK, they don't even carry guns ffs, yet Blacks raised in the UK will identify with the movement purely because they are the same race. Fact is, people identify with people that are like them.

Let's compare France with Japan - one of them has dangerous black/muslim ghettos, monthly terrorist attacks, huge racial tensions and risks its native ethnicity/culture disappearing in the next few generations - do you think anyone from Japan is thinking, "wow I want that for my country too !", yeah, no, and neither is anybody from Poland, Lithuania, Hungary, Korea or ANY country that hasn't been indoctrinated with white guilt and political correctness.

The other thing with multiculturalism is that it always comes with an attempt to deny the ethnic identity of the white majority, so it becomes not about ethnicities/cultures living side by side, but about one being denied an identity and forced to absorb the rest. This is true in Britain, Sweden, Germany - anywhere. How can a political vision based on guilt and self debasement ever be productive in in the long run? It only breeds resentment.

The only arguments I've seen in favour of multiculturalism generally revolve around food or soppy platitudes like "diversity is our strength!". It's really just an upper middle class fetishism for non-white cultures and for helping "those poor brown people" that white liberals think of as pets.

What are your thoughts ?

And the funny thing is, the government could have massively defused racial tensions if they stopped 3rd world immigration around the 1970's, we may have actually had that liberal utopian vision of a (slightly)diverse society free of hate.

A moderate and sensible government would have done this, but the establishment is seemingly full of anti-white marxist extremists who seek the total erasure of anything traditionally white and Christian.

Do you think that the UK would be homogeneous and monocultural without non-white people, foreigners, etc? If so, why?

Because that's the definition of homogeneity. Up until the 1950's England was 99% white English. Sounds pretty homogenous to me.

And monocultural?

I don't really consider these strong arguments. How do European countries benefit from middle eastern of African culture at all? Truth is they do not. The countries these people come from are corrupt, backwards, violent and unproductive.

A really interesting question actually that unfortunately I think will receive a lot negative responses.

Biologically speaking, there are good reasons to ensure a wide gene pool. For this purpose, having a society with people from all over world will mean the populous is comparatively stable and less likely to get wiped out by a certain disease for example.

You have listed a number of problems with having a diverse and multicultural society. I would like to ask you if you think this is a necessary outcome of a multicultural society. That is, whether it is possible to have a multicultural society without such issues? Because if so, then it simply that our society has not yet developed sufficiently to deal with such problems. Are you aware of any multicultural societies that have been flourishing?

Now, of course to promote multiculturalism I still need to present arguments for why it might be useful. It is important not to think of diversity as being good simply because it is diverse.
One possible argument is simply a question of efficiency. Each culture will have its own benefits, and by mingling we can share ideas, (including food) by taking the best from each. Further, this diversity can add more variety and interest into one's life and as we make life choices we may be more likely to find something we like in a more diverse society. Finally, there are reasons to think that a diverse society is more likely to be accepting of new ideas, which links to the efficiency argument but can also be important morally (in theory) in terms of tolerance.

Of course. Why wouldn't it be?

Chinese food is a result of very successful assimilation of all the now hidden ethnicities under the Han Chinese umbrella.

Cultural appropriation is real.

Cultures will always come into contact with each other, and having a mix within a country I think promotes understanding when dealing with other countries and cultures on the international stage. Yes, there used to be more homogenous populations within countries, but there also used to be a lot more conflict between countries. And people will always find ways to segregate sections of society, if not due to race than by wealth, intelligence, gender.

Also the disease is a fair point. No, we don't live in a movie, but a pandemic is still considered one of the most likely ways to chunk down the human population. Genetic diversity is good for survival of the human race, even if it's not from diseases but instead ability to adapt to, for example, a changing climate and potential dietary changes that may accompany that.

Tbh this sentence makes me think it's probably not worth trying to have a reasoned discussion with you, but we'll give it a go. We benefit from their culture in the artistic sense of the word in the same way we benefit from our own culture. New, varied, stimulus will always be good for the human condition.

As for the definition I feel you are aiming at of the customs and social behavior, lets just start with an article and go from there:

http://listverse.com/2013/12/26/10-developing-countries-with-unexpected-first-world-advantages/