Story of time 

Resources in society are limited, but human desires are unlimited, and the materials available to satisfy desires are limited, which will inevitably lead to the exploitation of one class to another. People in the upper class of society will try their best to plunder the limited materials in the world. When the cost of plundering is too high, the plundering will turn into direct huge profits. When the cake can be made bigger and the cost of exploitation is low, everything is gentle and gradual; when the cake can’t be made bigger and the cost of exploitation is high, the food will start to look ugly.