There is no commanding reason to suppose that a clear and accurate understanding of modern politics really is available to human beings at all. But those who earn a living by purporting to teach others how to understand it must at least try, as best they can, to understand it first for themselves. More pressingly and less parochially, those who choose to take political action need at least some conception of what they are attempting to do, and it is hard to see how they can hope to sustain such conceptions without some sense of what politics today is in fact about or what its human significance now really is.

This collection of essays focuses upon a single key issue in the somewhat groggy history of modern political thinking: the limits set to what is now politically possible by economic structures, processes, and activities. These limits have been a pressing preoccupation, for those in quest of practical just as much as theoretical understanding, for at least two centuries. They have prompted the most ambitious and confident of modern attempts to explain political processes and political development. In the eighteenth and nineteenth centuries, in the heyday first of liberal and then of socialist political ideologies, they underpinned the boldest expectations of moral and material progress and inspired great social and political movements devoted to bringing such progress about.