An article which mathematically articulates what we already know -- the reason that some people get richer than others is that they work smarter, and not just harder. Essentially, it points out that the disparity in income is less than the disparity in wealth. Similarly, as someone's wealth rises, the effectiveness of their networking and transaction-making improves, so that their ability to improve their wealth takes off.
But Leftists have always hated math. Whining and haranguing is so much easier.