In the capitalism post, generally defining the other sides positions and knocking them down is call strawman debate but that aside... The capitalist is the middle piece in this equation, he is the one that sees a need, gathers the resources to fill it and hires the workers to produce it. He does all of this at a risk that the workers don't share. Yet when he is right and benefits from taking that risk he is considered evil. The profit he makes exists solely because he saw a need and met it. And everyone benefits from that profit, the employees continue to be employed and make more money for their efforts.
Except that's nearly as raw and theoretical as the description to which you respond. Managers these days (they're the class that's really missing in the equation) don't see needs, they see wants -- and they also work hard at manipulating wants. And there's little risk, in most cases; the managers play with other people's money these days, rarely their own, in ways such that the actual capitalists -- the ones whose money is being risked -- have little say in the matter.
Human nature is not greedy, and by stating so you throw the whole concept of psychology in the trash. How socialism will come to be was explained already in deeper meaning. A description is best understood when one has a background in philosophy and has spent YEARS reading upon the subject rather a few days or weeks, reread this.
Yes, human nature is greedy. In the rare cases where humans appear to not be greedy, they are at the very least selfish. I've taken a fair amount of psych and of counseling courses, and in practical terms selfishness and yes, greed, are taken to be fundamental.
In your socialist utopia, people are supposed to just accept that what the majority say they need really is what they need. But that doesn't work even in the plant kingdom: plants compete. They don't care about their neighbors, they care about getting all the nutrients and water and sunlight they can. Except in a few rare species, that holds true for the animal kingdom.
Example, fighting for green energy is ONE key element to socialism. Green energy that is powered by solar panels and wind opens the doors to not requiring money to keep our world powered. You could fill the entire Nevada desert with solar panels and without ANY other plants using nuclear energy (Toxic waste that pollutes the earth and wastes millions to clean up) or coal which become a thing of the past because we LEARNED how dangerous those methods are. People continue sucking the blood of the earth (oil) and don't care that sink holes are developing around the earth causing massive damage and home losses and lets not forget the growing number of earthquakes. Just one example how Capitalism is damaging the planet because oil produces BILLIONS of dollars in profit for capitalists that make energy a business.
No, we use oil because it's cheaper and easier than other things, and people won't pay for something more expensive just to avoid the downside. And energy is a business because we need energy.
In fact it's a very democratic process: when we fill up at the pump, we vote for more oil. When we buy clothes made of synthetic fibers, we vote for more oil.
And we don't have all those vast, environment-mangling arrays of solar panels because they cost more. That's not dollars, that's
cost, the energy required to make, set up, and maintain them. So if we did your cover-the-desert bt with solar panels, energy bills would rise, not fall toward zero.
BTW, nuclear waste costing "millions to clean up" is false propaganda. We've know for decades how to deal with nuclear waste simply and cheaply -- that's not a technological problem, it's a political one (especially since a lot of what's classified as "nuclear waste" is less radioactive or dangerous than the Santa Monica freeway or the New Jersey Turnpike).