There are two instances I studied in which a community moved, amazingly, into an preexisting village built by other, earlier communalists. The Rappites were a German millenarian sect I mostly leave out of the story, even though they are fascinating, because they're focused on salvation and retreating from the world, as opposed to transforming it, like the other groups I write about.

I worry that I may have overstated the impact of Civil War on the utopians. By the time the Civil War comes, most of the communities were quite separated from the wider American society. Their rhetoric is still about transforming the world, but they're not having that much traffic with their neighbors.

The Enlightenment faith that things are getting a little bit better each decade becomes difficult to support. People recognized that there had just been a war that was worse than the war of 1812, and worse than the Revolution; things were clearly not getting better and better.

That to me was one of the most exciting, and weird puzzles of this book: how are the most religious people and the least religious people of their time all drawn to very similar visions of utopia?

But if you'd only ever lived in small wooden house in the middle of wilderness, it sounded much better. Especially because it provided intense community, and these people lived in incredible isolation.

They [Oneida people] didn't want to fix problems one at a time. If someone invited them to a feminist convention, their answer would have been, 'In the new world women will have total equality, so lets spend our energy creating that whole new world.' And to their credit, the women at Oneida probably had far greater practical equality than what any of the women gathered at Seneca Falls experienced in their lifetimes.

They're people who probably imagine that they would have had a better time in the past. I wouldn't imagine you'd encounter a lot of black people saying 'Oh, the '50s, that was when America was great.' It's very dangerous because the past was imperfect, and you can't go back anyway.