The fundamental paradox of politics: no society can be simultaneously fair, free, and equal

From How the Mind Works by Steven Pinker.

For millennia, kin emotions have shaped even the largest societies. The reach of parental love can extend over generations via gifts and inheritance. Parental love causes the fundamental paradox of politics: no society can be simultaneously fair, free, and equal. If it is fair, people who work harder can accumulate more. If it is free, people will give their wealth to their children. But then it cannot be equal, for some people will inherit wealth they did not earn. Ever since Plato called attention to these tradeoffs in The Republic, most political ideologies can be defined by the stance they take on which of these ideals should yield.