The historian Edward Hallett Carr was a man of strange paradoxes. An establishment figure by any definition - Cambridge graduate, Foreign Office functionary, Times leader-writer, advocate of appeasement in the 1930s - he was also, in later life, an ardent pro-Soviet. Although he was never actually a communist or indeed a Marxist - his views remained as conservative as ever - he was firmly on the "wrong" side of the great political divide.
Jonathan Haslam's task in writing his biography cannot have been easy. His subject left behind few personal papers and frustratingly little that tells us about his inner life and feelings. Throughout the latter decades of his long life, Carr did nothing but work. He refused outright to take holidays or to socialise in any way, to the despair of his successive wives. Some of the nastier stories that have circulated about his personal and marital behaviour - many of them traceable to Norman Stone's famously vicious London Review profile of him - seem not to be true, if we believe Haslam. Even so, the portrait that emerges is not an attractive one. Carr's apparent coldness can be explained in terms of a stiflingly conventional upbringing, which left him unable to express his own emotions or cope with strong emotion in others. Behind that facade lay a vulnerable man with a deep need to be loved. But if that was so, he certainly had an odd way of going about it.
The second half - over 40 years - of Carr's life was almost entirely devoted to his monumental History of Soviet Russia. This huge project, with its 14 volumes and thousands of pages, is already gathering dust and is little read, while Carr's continuing reputation rests mainly on a very small book, which he produced in a great hurry, What is History?. A meditation on the historian's role, it is, after nearly 40 years, still the most widely read and debated work of its kind. It also reveals another paradox in Carr himself. Few historians have seemed more impersonal in style and approach, less prone to advancing their own opinions. Soviet Russia is history written largely without individual human beings - even Lenin or Stalin become mere vectors for abstract social forces, while there is neither interest in nor compassion for the sufferings of the Russian peasantry under their rule. Yet What is History? is famous above all for its insistence that the key to understanding all historical writing lies in the personality and views of the writers themselves.
Carr spent much of his life, then, in studying a single revolution, one that shaped our entire century and which he believed was the carrier of humanity's future - but whose legacy had, within a few years of his death, vanished almost without trace. Fred Halliday's new book, by contrast, is a bold attempt to compare all the world's major revolutions of the past few centuries and evaluate the continuing significance of the entire phenomenon. If Carr in effect founded the discipline of international relations in Britain, Halliday has been that discipline's most influential internal critic. Carr became an admirer of communism without ever being a Marxist, while Halliday emerged as the converse: a Marxist of a critical and flexible kind, but quite free of illusions about the Soviet or any other supposedly Marxist regime. And Halliday has himself written, critically but with sympathy, about Carr's career and legacy.
As Halliday points out, international relations as an academic subject - an often dryly institutional and largely conservative one - has neglected the importance of revolutions in reshaping the world system. The most influential modern studies of revolutions have usually been inspired by historical sociology and have been very weak on their international dimensions. Halliday's work, straddling academic specialisms as sure-footedly as it does centuries and continents, seeks to correct both deficiencies. Unlike Carr, whose vision rarely extended beyond Europe and America, Halliday's is a truly global overview - and the most stimulating study of its subject to appear in many years.
Should a study of revolution be, in 1999, an obituary for something whose time has passed? Halliday suspects not. The vision - or nightmare - of world revolution as a unified process, driven by a single ideology, may indeed be dead. We have said farewell to the idea that one particular society forms the blueprint for humanity's future and that by studying it we can see the direction in which everyone is inevitably moving. Karl Marx, in his less cautious moods, thought that Victorian Britain was that blueprint. For decades, orthodox communists believed it of the Soviet Union; Carr came to share that view and thus became a kind of conservative Stalinist. Today, the USA (or rather an idealised image of it) is accepted as the model everyone else is bound to follow.
Halliday, without sharing any of those illusions, is alert to their continuing appeal. The political utopianism that drove communist dreams - or such latter-day successors as faith in a morally perfect world order based on Islam - has endless capacity for renewal. We live in a world that is more unequal than ever before, and global communications ensure that more people are bitterly aware of that inequality. For all the complacency that may reign among the world's richer and more stable societies, we probably haven't seen the end of the age of revolutions.