priestly groups in the temples had been more concerned with the records of the past and with the control of the inner space of the unseen than with outward military conquest. Hence, there was a clash between the priestly monopolizers of knowledge and those who wished to apply it abroad as new conquest and power. (This same clash now recurs between the university and the business world.) It was this kind of rivalry that inspired Ptolemy II to establish the great library at Alexandria as a center of imperial power. The huge staff of civil servants and scribes assigned to many specialist tasks was an antithetic and countervailing force to the Egyptian priesthood. The library could serve the political organization of empire in a way that did not interest the priesthood at all. A not-dissimilar rivalry is developing today between the atomic scientists and those who are mainly concerned with power. If we realize that the city as center was in the first instance an aggregate of threatened villagers, it is then easier for us to grasp how such harassed companies of refugees might fan out into an empire. The city-state as a form was not a response to peaceful commercial development, but a huddling for security amidst anarchy and dissolution. Thus the Greek city-state was a tribal form of inclusive and integral community, quite unlike the specialist cities that grew up as extensions of Roman military expansion. The Greek city-states eventually disintegrated by the usual action of specialist trading and the separation of functions that Mumford portrays in The City in History. The Roman cities began that way--as specialist operations of the central power. The Greek cities ended that way. If a city undertakes rural trade, it sets up at once a center-margin relation with the rural area in question. That relation involves taking staples and raw produce from the country in exchange for specialist products of the craftsman. If, on the other hand, the same city attempts to engage in overseas trade, it is more natural to "seed" another city center, as the Greeks did,