孟子金句：夫人必自侮，然后人侮之；家必自毁，而后人毁之；国必自伐，而后人伐之。
Mencius' golden quote: A person must first act foolishly, then others can humiliate him; a family must first be mired in discord and dispute, then others can swallow up the family's wealth; a country must first be mired in internal conflicts, then others can capture it.
Casteism is in fact a weapon used by the vested interests in each caste to further their own political and other interests. A caste society is very susceptible to foreign interference because all a foreign power needs to do is to control the upper castes, and the entire society (including the lower castes) would be enslaved by that foreign power. And it's not difficult to control the upper castes because the upper castes know that the lower castes don't support them, hence the upper castes prefer to rely on foreign powers for support and stability.
Casteism also enables "foreign settlers" to occupy the upper castes, trapping indigenous people in a permanent underclass (occupying the lower castes permanently). Casteism is already prevalent among White Americans, Australians, Brazilians, Canadians and New Zealanders who occupy the upper castes and trap their indigenous people in a permanent underclass (occupying the lower castes permanently). The P5 and G4 are also caste societies in their homelands. Casteism breeds class war, harms our social cohesion and polarises the society, hence casteism (by itself) violates the principles of FICA.