Cluster 5 -- Viscous Circle -- Piers Anthony -- (1982) (Version 2003.02.04)

Prolog

Three million years ago a galaxy-spanning civilization vanished, leaving only scattered evidences of its operations, in the form of derelict Ancient Sites and a strange pattern of surviving species. Some Sites are merely huge earthworks, long eroded and overrun by vegetation and development; others contain valuable artifacts of intense interest to scholars and technicians; and some few are "live" with operative equipment, sometimes self-animating.

All contemporary cultures of the known universe eagerly seek such Sites within their spheres of influence, as the technology of the Ancients was beyond anything known today.

For example, all cultures now suffer from Spherical Regression, being unable to maintain an advanced level of civilization at their perimeters. This represents an inherent limit on their expansion, and is thus a considerable annoyance. The Ancients seem not to have suffered this regression; they had some secret that enabled them to maintain their civilization at its optimum level throughout its entire region. Thus the discovery of a functioning Ancient Site is generally the signal for a mad intercultural scramble, in which the usual restraints of civilization hardly apply. Yet often the effects of such discoveries are other than anticipated, and have galaxy- or cluster-spanning ramifications.

Many of the technological innovations that have transformed contemporary interspecies society derive from the knowledge of the Ancients as discovered in their Sites. Two of the three major systems of transport and communication are examples: Mattermission and Transfer. Mattermission is the virtually instantaneous transmission of objects and creatures across interplanetary and interstellar distances. However, this mode is so expensive in energy that it can only be used on special occasions. Unrestricted use would result in the deterioration of the substance of the galaxy in that vicinity, as the binding atomic forces weaken. That is not healthy.

Transfer is the artificial shifting of the aura, or soul -- which includes personal identity, consciousness, and memory -- from one person to the body, or "host," of another. This system uses approximately one millionth the energy of Mattermission and automatically equips the Transferee with the language and background of the host, even when that host is a completely alien creature. With Transfer, interspecies commerce is feasible, and larger Spheres of Influence are practical. Empires can be formed and maintained.

An entire framework of Transfer has been developed, with many specialists. The Society of Hosts assumes responsibility for the welfare of hosts temporarily deprived of their auras. Its motto derives from Kipling:

"Lord God of Hosts, be with us yet,/Lest we forget -- lest we forget!" The Transferee who forgets his origin will fade into nonexistence. The military has trained people with intense auras to be transfer agents, who transfer to hosts among the cultures being spied on. The work is dangerous, since if the alien host dies before the mission is concluded, the visiting aura dies with it. But this is a notorious, dashing sort of employment with unique rewards.

Many seek it; few achieve it.

This is the story of one such agent.