I stopped reading after that, because that's not the real reason. The real reason is the way these people think.
(then I went back and read the article anyway and still think it misses the real reason)
Most solutions to the "1% problem" are based on building these legal cages of rules, regulations and taxes, where the "wild, untamed, mad" entrepreneurs are allowed to work.
But here's the catch - they are the ones who are supposed to build the cages for themselves !
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We need a new 1%. We need a third option besides Karl Marx and Adam Smith.
Both those theories are based on incomplete understanding of human psychology, sociology, information technology and so on. In simple words - both "capitalism" and "socialism" are old and wrong.
For example, nowhere will you see a mention of "advertising" in the theory of supply and demand. Not a single mention ! Check it out on wikipedia.
But advertising is a demand producing engine, which in turn generates supply and with some more advertising produces more demand and so on. There is no "economic equilibrium", there are marketing and PR budget limits !
We call it "economic theory" or even science, when in fact it's always been economic ideology with math added on top of it.
And any ideology is a consequence of learning and regurgitating the same half-truths until everyone deeply believes it to be the only truth.
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We also need a new Dale Carnegie and Napoleon Hill. The whole "achieve your full potential" idea. If achieving means earning and hoarding things, then this leads to a whole bunch of heartless, selfish assholes - what we have today. "But I've worked hard for it, so I deserve it!"
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So how do we do it ? I don't know, but I know that we have to do something about it if we are to survive as a species - the state of the biosphere is another manifestation of the same problem - the 1% god so rich at the same time as the planet got polluted, mined and abused.