Explanation:
Plato divided the people into three groups mainly based on their education and intelligence.
The people who proved to be more intelligent in terms of their education provided the education later to become philosophers and these philosophers when experienced were provided with the political powers. The people who do not show the strength of character and intelligence based on their natural aptitude either became warriors or workers.
This idea was good as each group of society has its roles and duties to play which could contribute to a good healthy society.