Utopia has become a vague term, synonymous almost with the Good Society or the Good Time. It is applied to the dreams and visions of all peoples and all times: from backward-looking myths of the Golden Age to the future prospect of a glorious Millennium, from Paradise Lost to Paradise Regained.

This book argues utopia should be seen as a much more specific tradition of social and political thought. It has cultural and historical boundaries. A Western concept, it arose in the West as a specific and highly original way of dealing with the novel problems of modern Western society. Its themes are the characteristic ones of modern Western social thought: power, inequality, democracy, science. But, as a form of imaginative fiction, its treatment of these themes is distinctive and compelling. Far from being merely fantasy or wish-fulfilment, utopia is a critical rehearsal of the dilemmas of modern society and, at the same time, a prescriptive account of the best way of resolving them.

From its first appearance in the "Utopia" of Thomas More in 1516, utopia has undergone numerous changes of focus and concern. But its form has remained remarkably resilient. As we approach the end of the second christian millennium, there are clear signs - for example the emergency of feminist and ecological utopias - that utopia has by no means exhausted is power either as a tool of critical analysis or as a constructive vision of future possibilities.