In Book IV of The Republic, the three classes of Greek society are outlined to the the businessman, the auxiliaries, and the Guardians. The Businessmen are those with desire/appetite for wealth, auxiliaries with the spirit to protect the city-state, and the guardians rule the city with their wisdom. According to Plato, justice is best achieved through allowing each class to accomplish its own tasks and not interfering with those of another.
In Confucian philosophy, Chinese society is separated in four classes: the gentleman/scholar (士), the agricultural class (農), the craftsman (工), and the tradesman(商) in the order of higher status in society. In his philosophy, this hierarchy achieves the most harmony. However, in contrary to Plato, Confucius states that "There should be no distinction of classes" (Analects 15.39) and supports the idea that any virtuous plebeian that cultivates his qualities can become a gentleman.
Within both social structures, men have the potential to reach a higher standing in their society but with categorical differences from one another. In Platonic society, each individual class attains its own idea of "success" - a wealthy trader, a military general, or a successful ruler. However, the Guardians are ultimately the rulers above the two other classes. In Confucian society, individuals are urged to practice virtue throughout life and gradually transcend the agricultural, craftsman, or tradesman classes into being a scholar.
Which social structure do you think is the better? Is it better to examine society under the lenses of justice or harmony? Furthermore, which one provides better class mobility and equal opportunity?