don't think I should be in the business of making big pronouncements about where we are now, but I would say that dissatisfaction is as acute now as it was then. What's different, and what I think we can learn from these people, despite their abundant folly, is that we're not using the future as the organizing principle for our critique.

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 Jacksonian era is generally talked about in terms of individualism, and the development of free market capitalism, and Victorian prudery. It was shocking to find a parallel history to that - a bunch of Americans with very different priorities. I stumbled on to these people, and then became completely fixated on them. The question that drove me was: how did these reasonable people adopt these extremely unreasonable ideas?

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.

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 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.

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.