In order to increase the reliability of its existence and not be swept off the face of the Earth by the global environmental crisis that has begun, each society needs to unite. To unite means to stop the internal struggle of people among themselves for resources. The engine of this struggle is human egoism. It reduces the reliability of the existence of societies. Natural selection, the units of which society, leads to the elimination of those of them in which the proportion of egoists is greater than in others. This will lead in the distant geological future to the extinction of egoists.