Kindle. Not great. A sapient ship (Ship!) has seeded the promising planets of the arm of a galaxy with humans and is now revisiting them for the nth time. There are rules of the game, of course, and Ship gets lonely so human companions are the order of the day. It's a bit fat Brunner but has more biology than sociology. The time travel mechanic does not work well; that and the exotic landscapes and biospheres evoke 1960s Doctor Who. The closing exegesis needed expansion and more weaving into the main text. There are some cute ideas (and some lazy historical lifts) that have effects too neat and tidy. Too much moralising again. You can see his interest flagged in this project as he was writing it.