He shared his oracular powers with a mind and a device left over from the last Rebirth, but the real problem was not rebuilding civilization, it was that another genus of creatures had arisen to claim inheritance of the world - the evolved. Strangely intelligent birds, whose priority was the elimination of the world's former masters.
The problem of man versus bird, complicated by the question of John's personal survival, presents a canvas worthy of the diverse talents of the author of A Case of Conscience and Cities in Flight.