In such a primitive society, unacquainted with letters, the higher education found but few aspirants. The only persons of scientific pretensions mentioned by Homer are the physicians (who are likewise surgeons) and the soothsayers. The former are highly appreciated, and are always chiefs. The soothsayers are the exponents of divine omens to the community, and occupy a kind of official position, like the Hebrew prophets. No artists, strictly speaking, are mentioned by Homer, except the bard, and he is much honored, as historian, teacher, and inspirer. We find, indeed, that Achilles and Paris are proficients in music; but such cases seem exceptional. Of artisans, several are mentioned--the worker in wood, the worker in horn and ivory, the potter (who uses the wheel), and so on. The existence of others is implied--the weaver, the mason, the metal-worker, etc. If there were no special schools in the heroic age, life was so lived as to be an excellent school. Then, as at all other times, it was extremely social, far more so than our modern life. This was due chiefly to three causes, (1) the smallness of the states, which made it possible for every citizen to know, and to feel his solidarity with, every other, (2) the absence of titles and formalities, which had not yet been introduced from the East, (3) the fact that the people, especially the men, spent the greater part of the day in the open air,--in the streets and agora,--and so were continually rubbing against each other. This sociality had much to do with the shaping of the Greek character, the salient elements of which are thus enumerated by Zeller, the historian of Greek philosophy: "A strong sense of freedom, combined with a rare susceptibility to proportion, form, and order, a keen relish for companionship in life and action, a social tendency which compelled the individual to combine with others, to submit to the general will, to follow the traditions of his family and his community." Between the simple social condition described by Homer and that for which Aristotle wrote, there intervened a period of at least six hundred years. During that time many great changes took place in the social and political life of the Greeks, demanding corresponding changes in education. These changes were due to several causes, (1) the natural human tendency toward freedom, (2) the influence of foreign nations, (3) the development of commerce, (4) the introduction of letters, (5) the rise of philosophy, (6) the Persian Wars. Though all these are closely interwoven with each other, there can be no harm in treating them separately.