'That is true.' I have explained to you the difference, and do you in return explain to me the unity.

But first let us consider whether any one who knows the name of a thing without the definition has any real knowledge of it.

Is not such knowledge a disgrace to a man of sense, especially where great and glorious truths are concerned?
and can any subject be more worthy of the attention of our legislators than the four virtues of which we are speaking--courage, temperance, justice, wisdom?
Ought not the magistrates and officers of the state to instruct the citizens in the nature of virtue and vice, instead of leaving them to be taught by some chance poet or sophist?
A city which is without instruction suffers the usual fate of cities in our day.

What then shall we do?
How shall we perfect the ideas of our guardians about virtue?
how shall we give our state a head and eyes?
'Yes, but how do you apply the figure ?' The city will be the body or trunk; the best of our young men will mount into the head or acropolis and be our eyes; they will look about them, and inform the elders, who are the mind and use the younger men as their instruments: together they will save the state.

Shall this be our constitution, or shall all be educated alike, and the special training be given up?
'That is impossible.' Let us then endeavour to attain to some more exact idea of education.