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.

One of the things that's amazing about reading the private writing of these folks is that they enthusiastically describe things which we have now seen, and which are widely regarded as unappealing. They'll write, "It's going to be beautiful, we're going to have a town of 1,000 stone buildings that are all identical." And we as modern readers think, we've seen that; that's bad Soviet architecture or a public housing project. Nobody fantasizes about living there.

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.

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.

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.

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.

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.