Ship Of Fools by Richard Paul Russo
Winner of the 2002 Philip K. Dick Award.
The story involves a vast starship named Argonos, with several thousand people on board. It's big enough to have warehouse-sized rooms that are used to hold old, broken-down equipment. It's big enough to have a huge cathedral. There are fields for growing grain and orchards for fruit, and a desert for recreational uses in which you can walk a straight line for at least 20 minutes. It has different levels for the various social strata on the ship...
Once upon a time, the starship presumably had a real purpose, but that was long, long ago. The people alive on the ship today were born on the ship. Now the ship is wandering from star system to star system in hopes of finding inhabited worlds to trade with. Or from the bishop's point of view, in hopes of finding people to convert. The lower classes would be happy with an uninhabited world where they could get off the ship and start over again - but the ship's elite has no intention of letting that happen.
The story is narrated by a character who views things with the mental perspective of an outsider (his personality has developed in conjunction to peopleís responses to his birth defects.)
A radio signal is received from a planet and they go to investigate. They find a couple of settlements where it appears that everyone was killed. At least some of the people were tortured or otherwise seriously injured. Even the infants were cruelly killed. After investigating for a while, itís decided by those in change that this is not a place they want to spend more time.
However, the lower social strata are ready to give anything else a try. There is a plot to steal shuttle ships to take more than 1000 of them down to the planet in hopes of starting over again.
After Argonos leaves the planet, it discovers an apparently derelict alien ship. They explore the ship, with various accidents and odd happenings. Eventually, they find an old woman who seems psychologically damaged. There is debate whether they should continue to explore the alien ship or whether it is a place they should stay away from.
Over the course of these events, we see the political machinations of the shipís elite and the church, some religious issues are raised, and there are debates over the nature of the alien ship and what is the proper course to deal with it.
I found the story-telling quality of the book quite good. The plot was generally good. My main reservation about the book involves the role of aliens in SF. Itís true, thereís no guarantee that weíll never encounter aliens that humans find dangerous. However, there tends to be too many of such books because itís too easy to write ďus vs. themĒ stories. As a result, I donít find that as satisfying. Iíd say the book is worth reading in any case, but the extent of you appreciation of the book may depend on how you respond to such factors.