Plato, part 4

The Republic, book IV

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428b-c But there are many kinds of knowledge in the city.
Of course.
Is it because of the knowledge possessed by its carpenters, then, that the city is to be called wise and sound in judgment?
Not at all. It's called skilled in carpentry because of that.
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What about the knowledge of bronze items or the like?
It isn't because of knowledge of that sort.
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It is guardianship, and it is possessed by those rulers we just now called complete guardians.
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428e Who do you think that there will be more of in our city, metal-workers or these true guardians?
There will be far more metal workers.
Indeed, of all those who are called by a certain name because they have some kind of knowledge, aren't the guardians the least numerous?
By far.
Then, a whole city established according to nature would be wise because of the smallest class and part in it, namely the governing or ruling one. And to this class, which seems to be by nature the smallest, belongs a share of the knowledge that alone among all the other kinds of knowledge is to be called wisdom. we read yesterday how the truth matters not in the education of the workers, because if they became well-educated they would see the truth for themselves and know what has been omitted from their education, and why those in charge chose to omit it. In other words, wisdom, which is the ability to discern truth, is much too dangerous to allow it to fall into the hands of the working class. ~stacy
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429c The city is courageous, then, because of a part of itself that has the power to preserve through everything its belief about what things are to be feared, namely, that they are the things and kinds of things that the lawgiver declared to be such in the course of educating it...