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 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.

There are Harvard grads, free thinkers, feminists, abolitionists, well-to-do people who want to go write poetry and live on a farm and cook and laugh and have a good time. As they themselves described it, it was an "inward facing" community. They were focusing on making a better existence for themselves, which I think is also the driving force of 20th century communalism in the US, the thought being that the world is corrupt, and we're going to build this little garden of innocence.

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.

The secular utopians basically said the exact same thing, they just took the Bible out of the equation. The religious and the secular groups recognized each other as fellow travellers. They exchanged newsletters and asked each other questions like, "What's a good soup pot to use if you're making dinner for 800 people?" They had these practical connections.

Some people just think utopians are idiots who are imagining rivers of candy and not really engaging with the world's ills, and sometimes that's surely the case, but I think that imagining the perfected society is a way of expressing your disgust with the current state of affairs.

Utopians don't say, 'The world's corrupt, women make less money, people of color are oppressed at every turn.' You don't list the problems of the world; you describe a world in which those things aren't the case. The critique is implicit and as a result it's kind of a positive critique. You're not listing what's bad, but rather what would be good - you're oriented toward this positive vision.