From a great interview on Alter.net –

“LP: Some say that if we redistribute income in a more equitable way, people won’t want to work as hard. Is that true? What happens to our motivation to work when things are so inequitable?

JS: One of the myths that I try to destroy is the myth that if we do anything about inequality it will weaken our economy. And that’s why the title of my book is The Price of Inequality. What I argue is that if we did attack these sources of inequality, we would actually have a stronger economy. We’re paying a high price for this inequality. Now, one of the mischaracterizations of those of us who want a more equal or fairer society, is that we’re in favor of total equality, and that would mean that there would be no incentives. That’s not the issue. The question is whether we could ameliorate some of the inequality — reduce some of the inequality by, for instance, curtailing monopoly power, curtailing predatory lending, curtailing abusive credit card practices, curtailing the abuses of CEO pay. All of those kinds of things, what I generically call “rent seeking,” are things that distort and destroy our economy. 

So in fact, part of the problem of low taxes at the top is that since so much of the income at the very top is a result of rent seeking, when we lower the taxes, we’re effectively lowering the taxes on rent seeking, and we’re encouraging rent-seeking activities. When we have special provisions for capital gains that allow speculations to be taxed at a lower rate than people who work for a living, we encourage speculation. So that if you look at the design bit of our tax structure, it does create incentives for doing the wrong thing.”

    The burgeoning inequality in the US is rotting civil society away, the sooner the US decides to address the issue the better.