Of the primary emotions, fear is the one that bears most directly on survival. Children show fear. Adults try not to, maybe because it's shameful, or, in some circumstances, dangerous. The fear response is automatic, though, and your body runs through its reflexes whether you want it to or not.
Sebastian JungerIronically, though our society of affluence brings safety and stability, it doesn't bring psychological health. As wealth goes up, suicide and depression rates tend to go up. I read one study that compared women in North America with women in Nigeria, and the group with the highest rates of depression was urban North American women, which is the wealthiest. Now, there are obviously huge stresses that come with poverty, but the poorer the society, the more collaborative people have to be.
Sebastian Junger