Men and women of courage questioned the belief systems that bound them, set out on journeys into the unknown and returned knowing more. Nevertheless, even though it is in society's interests, it seldom, if ever, encourages freedom. The responsibility can fall only in one place - at the feet of the individual who has once braved the journey and returns to teach it. This of course is the essence of Plato's Republic. The problem with Plato's king is, as king he could not serve society.
Society even defines kings, and the lesser serves the greater.
If the King were greater, society would bow its knee to him. Therefore the task can only fall to one who has the courage to venture out, and the humility to bow their knee to the authority of society, even though it often leads to excommunication or worse, death. This is the role of the true teacher - one adventurous and meek enough to learn and teach. It is a lofty vision to believe all people should, to one degree or another, have the opportunity to voyage into the terrifying realm of truth and freedom. This is the vision of education.