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?

Utopian fiction is really boring. I had to read a lot of it, and it's not that much fun. But they're fascinating to me as historical documents. Cabet [Icaria's founder and author of the utopian novel, Travels in Icaria], is writing in the 1830s, and his idea of the perfect society reveals a lot about his time. But his book is uniquely bad.

I was really interested in 20th century communalism and alternative communities, the boom of communes in the 60s and 70s. That led me back to the 19th century. I was shocked to find what I would describe as far more utopian ideas in the 19th century than in the 20th century. Not only were the ideas so extreme, but surprising people were adopting them.

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.

Because the utopian's worldview was framed around moving toward this perfected future, it helped stimulate the private exertions that add up to social progress. Progress is work. People need to build things and sacrifice and have a harder life for things to get better. On its own, I don't think even the most brilliant critique stimulates that kind of effort as well as an appealing vision of the future.

They [Rappites] were moving from Southern Indiana to Pennsylvania, where they had originally settled when they came from Germany. They were looking for someone who wanted to buy a pre-built town, which wouldn't have been appropriate for any kind of normal settlement. That's when Robert Owen [Welsh industrialist and utopian socialist] buys the village and founds New Harmony.