Plato is the earliest important educational thinker. He saw education as the key to creating and sustaining his Republic. He advocated extreme methods: removing children from their mothers' care and raising them as wards of the state, with great care being taken to differentiate children suitable to the various castes, the highest receiving the most education, so that they could act as guardians of the city and care for the less able. Education would be holistic, including facts, skills, physical discipline, and music and art, which he considered the highest form of endeavour. For Plato the individual was best served by being subordinated to a just society. Plato's belief that talent was distributed non-genetically and thus must be found in children born to all classes moves us away from aristocracy, and Plato builds on this by insisting that those suitably gifted are to be trained by the state so that they may be qualified to assume the role of a ruling class. What this establishes is essentially a system of selective public education premised on the assumption that an educated minority of the population are, by virtue of their education (and inborn educability), sufficient for healthy governance.
Plato should be considered foundational for democratic philosophies of education both because later key thinkers treat him as such, and because, while Plato's methods are autocratic and his motives meritocratic, he nonetheless prefigures much later democratic philosophy of education. This is different in degree rather than kind from most versions of, say, the American experiment with democratic education, which has usually assumed that only some students should be educated to the fullest, while others may, acceptably, fall by the wayside.
Only fragments of Aristotle's treatise On Education are still in existence. We thus know of his philosophy of education primarily through brief passages in other works. Aristotle considered human nature, habit and reason to be equally important forces to be cultivated in education. Thus, for example, he considered repetition to be a key tool to develop good habits. The teacher was to lead the student systematically; this differs, for example, from Socrates' emphasis on questioning his listeners to bring out their own ideas (though the comparison is perhaps incongruous since Socrates was dealing with adults).
Aristotle placed great emphasis on balancing the theoretical and practical aspects of subjects taught. Subjects he explicitly mentions as being important included reading, writing and mathematics; music; physical education; literature and history; and a wide range of sciences. He also mentioned the importance of play.
One of education's primary missions for Aristotle, perhaps its most important, was to produce good and virtuous citizens for the polis. All who have meditated on the art of governing mankind have been convinced that the fate of empires depends on the education of youth.
Rousseau, though he paid his respects to Plato's philosophy, rejected it as impractical due to the decayed state of society. Rousseau also had a different theory of human development; where Plato held that people are born with