It is true that knowledge can set us free from some fears, but they can start others - like when will the vulcano in Yellowstone pop? When will worldwar 3 start? When will the virus come that will kill us all? And other sunny ideas...
The other argument was that our technology is incredible and can create many things, but without any wisdom on what to do with it. So though knowledge is not evil in itself it can be turned to evil, and so often is. Maybe we are not ready so have so much knowledge.
I do not see why we should be like that by nature. I have worked with children many years, and while many are like you say, they are normally not only like that, but can also be helpfull and kind to others, depending on situations and their own mood at the moment.Sadly, I have to go along with the idea that we are born brutes. I'm having the pleasure of watching my two granddaughters grow up, having the time to really observe them that I didn't really have with my own children. And I'm finding that children are greedy, selfish and cruel on their own. We have to teach them to share and not to hit others and that they can't have everything they want. We have the capacity to be good, but it is not innate within us. It's a learning process, lifelong.
But aren't siblings often quite hard on each other?