But suddenly they become very real, and very potent forces, in human social groups where survival itself is uncertain. The concepts of good and evil were integrated into the culture. Parents taught children to share, to be honest, and to consider the feelings of others. The concepts became internalized, along with all the whole vast array of emotions, both powerful and subtle, that go with them. For example, a man feels instinctive rage when he discovers his wife with another man.
People feel spontaneous resentment upon witnessing the selfish or deceitful behavior of others.
They experience fear and anxiety when they imagine themselves ostracized by the group for engaging in forbidden acts. And they feel pride after being praised for making a major contribution to the group. All of these pleasant and unpleasant emotions form a system of positive and negative reinforcement that molds the behavior of individuals and keeps the group working successfully as a unit. The importance of the group is paramount, for we know that human beings must band together in order to survive. Groups with a highly developed morality survived in greater numbers than those without it, thus the genetic predisposition increased in the population.