Your polygon parable shows that phase segregation is a natural result of like-dissolves-like (something chemists have long known), and will likely occur natural

Your polygon parable shows that phase segregation is a natural result of like-dissolves-like (something chemists have long known), and will likely occur naturally as a result of individual choices rather than malicious effects. While this is interesting - it provides strong evidence that various racial disparities may NOT be the result of racism - it doesn't support the Matthew Effect at all. Black Americans are clearly less advantaged than white Americans. No one disputes this. The question is why this will result in differing exponential growth rates. You haven't provided a mechanism for this. Indians and Chinese are also clearly more disadvantaged than black Americans - just think how much effort they need to go through simply to get the natural advantage of being legally permitted to work in the US. Yet their growth rate (in terms of life expectancy, income, etc) is higher. This demonstrates that your "clearly less advantaged" theory does not imply differing exponential growth rates. Also, your source about within-country inequality (i.e. Piketty) is silly. Even if we only assign 3/5 weight to Indians and Chinese people [1], inequality has still decreased. Any discussion of inequality which mentions Balzac more frequently than India/China/Africa (such as Piketty's book) is hopelessly myopic. [1] Is there a reason that the Indian people around me (I'm in India) deserve less weight than Frenchies? I'd love an answer more detailed than "Trump 2016!!! WOO YEAH!"