[RJM Corbet]

No they're not dependent on them in any way. Nor are they allowed to interfere with them in any way whatsoever -- very important -- although they may advise. The two civilizations have little to do with one another, but the events of the book first link them and then separate them forever. And I'm not giving away any more of the story, dude! I have corrected 'appendices' and substituted 'follies' with: 'from our own absurd treatment of the planet that supports us' -- while there was still time to edit. Lithos? I guess they mine the moons, the asteroids and the uninhabited worlds too? Thanks for that ...