/kloc-After the age of 0/7, the children of civilians who have finished primary school leave school to look for jobs in the society and become manual workers who are willing to contribute to society. The children of slave owners should enter the Youth Military Training Corps to receive three years of military physical training, and continue to learn theoretical knowledge, learn subjects that must be mastered as soldiers, that is, arithmetic, geometry, astronomy, music (Plato called it "four arts"), and carry out patriotic education in order to train brave soldiers in the country. After this stage of study, most students will serve in the army, while a few talented students will continue to study and study the "Four Arts" and philosophy in special institutions set up by the state, and eventually become state officials or philosophers.