Ben tells Jubal he did not accept the ménage à trois offer. In fact, he was in such a hurry to bail that he almost fell six stories down the bounce tube, but something (Mike, maybe?) caught him.
Jubal and Ben consider why Ben had the reaction he did to Mike's invitation. (Um, because it's completely random?)
Ben argues that the behavior is shocking, but Jubal thinks the cultural heritage and moral code Ben was raised with might be to blame.
If this is starting to sound very similar to the Duke/Jubal talk from earlier in the book, that's because it is very similar to the Duke/Jubal talk from earlier in the book. But don't skip it assuming it's recycled material. There's a lot of good stuff here.
True to form, Jubal discusses past cultures that have promoted the sharing of spouses including Eskimos and early Christian sects.
They discover, just as Jill suggested in the last chapter, that Ben's real issue is the jealousy he feels for Jill and the thought of sharing her.
Jubal bets Ben a thousand dollars that Mike did indeed perform the miracles. He ponies up another thousand, claiming that if Ben returned to the Nest, the people there would accept him.
A day later, Ben wires Jubal two thousand dollars.
A week later, Jubal receives a message saying that Ben is studying the Martian language.