Open the borders and let those that want to move there.
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Yeah I don't think it will solve the problem too... not in a long run. All though we will all see more open borders and more immigrants all over developed world. Not because we love immigrants and diversity but because we NEED them or our economy will go down the toilet. Perpetual growth of our economies that we all see as necessary demand more people...and not only in employment sense...but also in new consumers sense.
Population globally may even explode ( especially if we do not make those poor countries rich, as we are ,LOL).But in this movie they say that statistics told us, if nothing changes, in the year 3100 there will be JUST ONE Japanese man in Japan. Demographics are going to change greatly all over the world. How this is going to feel ? Maybe in countries that are melting pots where nationality is not recognized (or important) like USA or even one day Australia it will not  be big deal. But what about Europe? Who is going to "inherit" Italy? Romanians, Albanians, Africans? Do not get me wrong I have nothing against these people but isn't it going to be a big loss if world loses Italians? Japanese on the other hand do not want immigrants on their soil. They would rather have robots...If they stay this course they will vanish from earth. Which is also great loss! Looks like some nations are going to be endangered species. We are trying to save diversity in nature ( animals , plants), what about this then?    
And about religion. Obviously those religions like Islam ( and probably others but I do not think  Catholics are in this group looking at their numbers) who are against contraception, abortion etc. will supposedly thrive...and overcome others. Especially if we do not help them higher their standard of living , which can only be done by women's employment ...I suppose...Then again if they overcome others  it will be only just...This was our choice...Just few thoughts...


Science without religion is lame, religion without science is blind...Albert Einstein