This seems repeating Ibn Khaldun's theories from XIV century. In subsistence economies surplus is used primarily for fostering social relations and creating so

This seems repeating Ibn Khaldun's theories from XIV century. In subsistence economies surplus is used primarily for fostering social relations and creating social obligations which one can call upon when times get though. And in subsistence economy sooner or later they will. As more added value is created socioeconomic relations get more complicated and they become based on money.