A brush with the intrepid fox

Books: Justin Wintle hails the thinker who taught that disunity is strength

The Proper Study of Mankind: an anthology of essays by Isaiah Berlin, Chatto, pounds 25

Sir Isaiah Berlin was an influence before I knew anything about him. At public school I was fortunate to be taught history by a Balliol man. "Right, you lot," he began one morning, "today you're going to imbibe Karl Marx."

Cue sharp intake of breath by twenty-odd privileged prats. For most of us, Harold Wilson was anathema enough. Marx meant the USSR which meant the Cuban missile crisis which meant having come within a hair's breath of extinction at the hands of rabid ideologues. Had Mr Cozzens finally flipped?

But the lesson was no attempt at indoctrination. Rather we were introduced to Marx in the context of his times: an indomitable bookworm who offered fresh solutions to problems that had taxed Europe's finest minds. We were reminded of the central preoccupations of the Enlightenment, and given a purchase on Hegelian metaphysics. History was never the same again. Cozzens knew his Isaiah Berlin. When later I read Berlin's monograph, I found it strangely familiar - and profoundly impressive. Published in 1939, Karl Marx is still in print (Fontana) and still the best introduction to its subject. Berlin may not especially like Marxian thought, but at the critical moments his exposition allows Marx to stand, even shine, in his own light.

This is typical of Berlin. His concern is nearly always with larger moral issues, but he never succumbs to indignation. Instead he labours diligently and eloquently at the rockface of other men's thought. The Proper Study of Mankind is testimony to these qualities, even though, as a sampler of Berlin, it fails to exhibit his full range. Henry Hardy and Roger Hausheer, editors of these 17 items, have a mission: to demonstrate that Berlin qualifies as a major thinker in his own right, that his work, which has sallied forth as essays and lectures, needs to be seen as a whole.

Are the claims substantiated? If not, then it is only because Berlin himself has outsmarted them. One of his bravura pieces is "The Hedgehog and the Fox" (1953), which takes as its starting point a fragment of Antilochus: "The fox knows many things but the hedgehog knows one big thing." Berlin applies this to the author of War and Peace.

Tolstoy is torn, he argues, between rival, and finally incompatible, positions. Foxes are free-floating empiricists. They respond to events as they occur. Hedgehogs are rationalists, committed to the myth that all phenomena are reductible to a single system. They insist all knowledge forms a seamless unity. As a novelist, Tolstoy is foxily alert to the moment. He regularly captures the fleeting and the ineffable. It is when he turns his attention to the theory of history that the hedgehog bristles into view. Human beings, he suggests, are never more than symptoms of great but unseen forces - fate!

Berlin's own cosmogeny, peopled by European and Russian thinkers, abounds with both species, pluralists and monists. He sides with the pluralists. Monism, he asserts many times in these pages, is the stuff of authoritarianism; and as a Jew born in Latvia, who witnessed the Revolution in Moscow before his family emigrated, he has every reason to distrust any system. If Hegel was Marx's mentor, he also provided key strands of Nazism.

Berlin's outstanding contribution to political theory has been his espousal of "value pluralism". There is not (he advances), nor can there be, a true convergence of human values. Even in one culture, such values are innately rivalrous. Man is born to disagree. The business of politics is not to attempt to resolve all differences, but to accommodate a natural diversity.

In "Two Concepts of Liberty", Berlin orchestrates his philosophy with the notion of "negative liberty", insisting that freedom cannot be legislated. Only the removal of restraints can enable such a subjective affair.

Typically, it is communist, fascist and ultra-nationalist regimes that peddle "positive" liberty. What their ideologies share is the monist ideal. Since the ultimate source of this error is Socrates, Berlin in effect challenges the mainstream of western thought.

Even so, it is difficult to conceive of Sir Isaiah in quite such radical terms. His lucid, polished discourse tempers his own theses so that his prose becomes a mosaic of the widest possible interplay of ideas. Yet such discourse is itself a form of overview, so that it becomes unclear whether Berlin is after all a fox.

Or perhaps he's a giraffe: an Oxford luminary observing other creatures at play, but sometimes forgetful of the implications of his own loftiness. This species custom-evolved, it would sometimes seem, for the ivory tower.

More pertinently, there is the recurring suspicion, articulated by Berlin himself, that fulfilment need not depend on freedom at all. Regimes may not suit everyone, but they suit some. Thus Berlin's edifice begins to crumble even as it rises, fragmenting back into the open-minded pluralism where, happily, it originates.