(3) The work begun by nature, and continued by habit or exercise, was completed and crowned by instruction. This had, according to the Greek, two functions, (_a_) to make action free, by making it rational, (_b_) to make possible an advance to original action. Nature and habit left men thralls, governed by instincts and prescriptions; instruction, revelation of the grounds of action, set them free. Such freedom, based on insight, was to the thinkers of Greece the realization of manhood, or rather, of the divine in man. "The truth shall make you free"--no one understood this better than they. Hence, with all their steady insistence upon practice in education, they never regarded it as the ultimate end, or as any end at all, except when guided by insight, the fruit of instruction. A practicality leading to no widening of the spiritual horizon, to no freeing insight, was to them illiberal, slavish, paltry--"banausic," they said,--degrading both to body and soul. CHAPTER IV SUBJECTS FOR EDUCATION It is right that Greeks should rule over barbarians, but not barbarians over Greeks; for those are slaves, but these are free men.--Euripides. Barbarian and slave are by nature the same.--Aristotle. Nature endeavors to make the bodies of freemen and slaves different; the latter strong for necessary use, the former erect and useless for such operations, but useful for political life.... It is evident, then, that by nature some men are free, others slaves, and that, in the case of the latter, slavery is both beneficial and just.--_Id._ Instruction, though it plainly has power to direct and stimulate the generous among the young ... is as plainly powerless to turn the mass of men to nobility and goodness (_Kalokagathia_). For it is not in their nature to be guided by reverence, but by fear, nor to abstain from low things because they are disgraceful, but (only) because they entail punishment.--_Id._