"The man is wolf to man" - Hobbes
One creates this assumption because people have always been in the pursuit of ones own safety, putting one's self before all others.
The thing is, whilst man is man's greatest foe, man is also his own best ally.
Human beings are social beings which cannot survive longer periods of time without interaction. The question is, how to quell negative interactions.
The answer is in a philosofical view of life:
If we'd all be in the same boat, all know each other and share the same limitations and freedom in this small scale, who would actually have jealousy of someone else?
There'd be no material posessions to distinguish one from another, there'd be no reason to steal, there'd be no reason to disrupt the natural flow of actions.
And if there would be any disruption, the whole community, as a caring, nurturing force, would think together on a way of solving the issue with trust, and not violence or punishment.
Most of all psicological disorders and negative emotions stem from the lack of love in the upbringing and growth of a person.
In a caring, trustful, simple and small-scale habitat, most problems would not even occur.
