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.

The thing that had fueled these utopian communities was a literal belief, and not just a general sense of optimism, that the earth was about to become a paradise. That idea cannot hold water after the war.

The fatal flaw of most utopian visions is that they're fundamentally static, and that's not a comfortable place for humans to live. Fourier was very good at imagining a utopia that is constantly changing and very busy, but a vision of paradise that would have been most tantalizing to an underfed overworked factory worker in 1840 doesn't have much appeal in fiction because it's not a story.

The religious and irreligious are agreeing with each other almost all the time. Their rhetoric is the same, and their plans are the same. Through slightly different interpretations, they all think the same thing is going to happen, that the Earth is going to be perfected and that humans are going to do the work of perfecting it.

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?

Margaret Fuller was already a celebrity, travelling around the world. Emerson, who was the axis around which that whole community turned, just didn't like Fourier's ideas very much. He thought it was all too rigid and programmatic. He said, "Fourier had skipped no fact but one, namely life." He thought it was an inhumane system - the day is scheduled too precisely. He didn't think it would work, and he was right.

Atheist isn't really the right word because they tended to believe in some sort of Enlightenment, capital 'N' Nature kind of god. But these were people who in their times were criticized as infidels.