For those on a mobile device (the "Join the Conversation" feature wasn't working for me on my phone), here is the top comment at time of writing this. User 'spm' writes:

I think people are missing the larger point these type of graphs show. Of course there has always been rich and poor in America. And the bottom poor in America are doing better than the "middle class" in Zimbabwe or some other third world country. But the real point of these type of graphs is that return on PRODUCTIVITY has skewed exponentially toward the wealthy. It's evidence that supply side economics does not work. THERE IS NO TRICKLE DOWN lol. The rich just get richer while inflation and stagnant wages make the poor get poorer. This is not political rhetoric or demonization of the wealthy. It's simply reality and can be substantiated with data and numbers.

People also need to stop with this logical fallacy about the wealthy working hard for their wealth. Typically that's not how it works , wealthy people typically increase their wealth exponentially by NOT working hard...instead choosing to use this little thing called....the stock market. The whole point of the stock market is to make your money work for you...and get more of it. That little 15K you've slaved to get into your 401K, yea someone makes that in a week....off of dividends lol. Even CEOs who make hundreds of millions of dollars do not work in the traditional sense. They get paid to make decisions, and often times those decisions are out right HORRIBLE affecting the lives of the middle class and poor who work under them(if they don't get laid off). Luckily many CEOs have golden parachutes which takes care of that pesky notion of accountability which they can then use to make investments(and continue to grow their wealth exponentially) in the case that they are fired

You mention that their wealth is put into the stock market, which is only part of the story since most of that wealth is in a variety of investments with a potential return of which the stock market is only one example. That wealth also provides the capital that funds many startups or help other companies grow. Some of these investments are rubbish, as you say, but the rubbish investments reduces the value of the portfolio. The wealth that remains and grows are because they are generally managed well by the wealthy individuals or whoever is managing it for them, picking the right investments. This is a good thing and there is a kind of trickle down that results because of this, in the form of investments being allocated to people worthy to invest in.

What is the difference between a good investment and a rubbish one? A good investment is one where you invest in a company that produces a product for which there is demand greater than supply. And where does demand come from?

You have to be able to produce the product or deliver the service at a lower cost than people are willing to pay for it. Demand is just one factor that affects how much they are willing to pay. The most basic example is an investment in an invention that saves people time and money, so people are willing to pay a portion of the time and money they are saving. Demand is then influenced by various things, including how important or significant this saving is, and how many other options they have to achieve similar savings, including alternatives from competitors. A good investor would be someone who understands and consider all these factors.

When you have a large wealth gap it simply becomes less profitable to produce goods that are of high utility to those with less money.

So you may get more bang for your buck by investing in companies that give labour saving benefits to the already wealthy, thus net increasing unemployment. With less income disparity the best goods to invest in may be ones which provide quality of living improvements across the spectrum.

Wrong again, there is no such thing, than well investments. Nobody beats the market portfolio in the long run - even not Warren Buffet.

You have to be a bit careful talking about things in terms of "working hard" since this is hard to define.

Apart from a few who have inherited enough wealth to throw it all at a financial advisor and say "Keep me solvent so I can chill and do coke for the rest of my life" you're going to have to do something.

Some might consider spending long hours doing research as to the best way to get the most growth out of your money to be hard work. Whereas others may think that anything which isn't back breaking manual labour isn't really work at all.

Exactly - I used to feel guilty that I wasn't "getting my hands dirty" and instead working in front of a computer all day. Then it comes out that actually sitting all day might be bad for your health. Someone will undoubtedly chime in with the whole "market value" argument. But one point has always stuck with me: the right decisions are important, but how much work would get done with "the right decisions" and no one to execute them? Is making the right decision really worth more than all the work to implement it?