Can you show any study in psychology for this belief of yours?
First, you need to understand what socialism is.
All socialism is, is any system of government and/or commercial enterprise that gives a say within the decision-making process to the people being effected by the decisions being made.
Here is an article showing unambiguously that competition eliminates less productive firms and cause an increase in productivity for surviving firms.
Google Scholar
I have no doubt there are thousands of essays declaring how greed and competition are great for humanity. If you want to be an economics professor in this culture you damn well better be able to write those essays. And you damn well better be willing to preach the "greed is good" dogma to your students. Because if you can't or won't do that, you aren't going to be professing economics in this country for long. Or in most any other.
But the big lie of "greed is good" (for humanity) is based on slyly redefining greed as "ambition", so as to avoid having to face the predatory essence of greed. But greed is not ambition. And in fact, greed is more often than not antithetical to ambition. It's lazy, and selfish. It wants something for nothing. Greed wants the laborers to do all the work while it takes all the profits. Then it tells us all ow hard it worked at doing this, so it deserves all the profits.
And the big lie of "competition is good" (for humanity) is based on their hiding the 'goal posts' from us. They want us to believe that they're all competing to make the best products for the most reasonable prices. When in fact they aren't the least bit interested in doing that. What they want, and are competing to achieve, is to sell us the cheapest product they can get away with for the highest possible price. And they don't necessarily even want to sell more of them. They'd much rather sell 10 crappy widgets for $10 each than sell 100 crappy widgets for $1 each. Especially if the crappy widgets only cost them $.10 to make.
This idea that capitalist competition is happening in the name of our collective well-being is complete BS. Yet they've had their toadies in the colleges and news media preaching this BS for generations.