A large number, however, from among the poorer classes were compelled to work with their own hands; so these, as well as the slaves, required technical instruction. Some indications survive as to the manner in which this was imparted. Trades were mostly hereditary; “the sons of the craftsmen learn their fathers’ trade, so far as their fathers and their friends of the same trade can teach it.”[102] But others might also learn. Xenophon mentions such cases. “When you apprentice a boy to a trade,” he says, “you draw up a statement of what you mean him to be taught,”[103] and the fees were not paid unless this agreement was carried out. The _Kleitophon_[104] mentions as the two functions of the builder or the doctor the practising of their profession and the teaching of pupils. The _Republic_[105] says: “If owing to poverty a craftsman is unable to provide the books and other requisites of his calling, his work will suffer, and his sons and any others whom he may be teaching will not learn their trade so well.” The teaching of building is mentioned in the _Gorgias_.[106] In the _Republic_[107] Plato states that the παῖδες [paides] of the potters――a word which will include both sons and apprentices――act as servants and look on for a long time before they are allowed to try their hands themselves at making pots. “To learn pot-making on a wine-jar” was a proverb for beginning with the most difficult part of a subject. The pupils of a doctor named Pittalos are mentioned in the _Acharnians_ of Aristophanes.[108] The comic poets of the early third century contain several references to cookery-schools. Sosipater makes one cook say that his pupils must learn astrology, architecture, and strategy before they come to him, just as Plato had exacted a preliminary knowledge of mathematics from his disciples. Euphron gives ten months as the minimum length of a course of cookery. Aristotle mentions a man at Syracuse who taught slaves how to wait at table, and perform their household duties: perhaps the play of Pherekrates[109] entitled _The Slave-Teacher_ may have dealt with a similar case. From these fragments a picture can be drawn of a regular system of apprenticeship by which the knowledge of the trades was handed down. Solon, wishing to encourage Athenian manufactures, had enacted that if a father did not have his son taught some trade, he could not legally demand to be supported in his old age.[110] But the general opinion of Hellas still maintained that “technical instruction and all teaching which aimed only at money-making was vulgar and did not deserve the name of education. True education aimed solely at virtue, making the child yearn to be a good citizen, skilled to rule and to obey.”[111] For all the gold on the earth and under it, according to Plato, could not pay the price of virtue, or deserve to be given in exchange for a man’s soul. Thus the Spartans and Cretans did not stand alone, but had