Cordies, Nomads And Galactics

The Stellar Union Coordination Service, or "Cordies," feature or are referred to in four successive installments of Poul Anderson's Psychotechnic History:

"Virgin Planet" shows us what a Cordy Chief thinks of a stellagraphic survey man;

"Teucan" tells us what a Trader thinks of Cordies;

"The Pirate" shows us how Cordy field agent Trevelyan Micah deals with an entrepreneur;

The Peregrine shows us how Trevelyan cooperates with and later joins the Nomads.

Thus, this one Service introduces us to four other sections of interstellar society. The Service cannot survive the collapse of the Union or the subsequent Third Dark Ages but the Nomads, especially when guided by Trevelyan and other ex-Cordies, are equipped to survive and to influence later civilizations.

The Nomads, like James Blish's Okies, perpetually travel through space, trading and stopping on planets but never to stay. In Blish's Cities in Flight, cities, lifted by antigravity and an FTL drive, leave Earth for economic reasons, thus de-urbanizing Earth. In Anderson's Psychotechnic History, Earth is de-urbanized because technological communication makes cities redundant but they re-emerge on the frontier as spaceports. Much later, in Galactic Civilization, cities are even rarer when individuals are able to cross space without vehicles by controlling cosmic energies.