It is impossible not to see a biographical element at work in Ernest Gellner’s insistence on the need for radical rethinking of our place in history. For his life made him rather like the ‘pure visitor’ whose detachment he recommended as a cognitive strategy. Both his parents were German-speaking and of Jewish background, and both were of lower middle-class provincial background. Once in Prague, people of this sort changed their allegiance, from German to Czech, to accommodate themselves to the way in which sheer demographic weight created a new form of society at the end of the nineteenth century. Of course, this shift in identities was not total: allegiance often remained to German as a world language, whilst anti-semitism placed limits on imagined belonging—making Zionism a further existential option. It is scarcely surprising that this world drove Gellner to think about nationalism, for it had the same effect on Hans Kohn, Karl Deutsch, Eugen Lemberg and Miroslav Hroch. In Gellner’s case the need to rethink identity and position was much exacerbated by the war and its aftermath. The family’s loyalty to Masaryk’s republic was sufficiently strong to have kept them in Prague until after the German occupation, with the escapes that followed being exceptionally hazardous. After a year at Oxford, Gellner then served in the Czech Armoured Brigade at the end of the war, taking part in victory parades in 1945 in Plzen and Prague. But everything in the city he loved so much had changed for the worst: the Jews had been killed, and the Germans were being viciously expelled. Aware that the latter act would draw the Czechs into the Russian orbit, through fear of German revenge, Gellner opted in a matter of months for the life of an emigre, convinced that Czechoslovakia would enter a period of darkness similar to that which followed defeat at the Battle of the White Mountain in 1618. After finishing his studies at Oxford, he lectured briefly in Edinburgh, before then spending his formal academic career at the London School of Economics (1949–84) and Cambridge (1984–93). His work in all these places broke out of disciplinary boundaries, in large part because it was marked by a sense of moral urgency. What then were Gellner’s conclusions? How exactly did he characterize the conditions of our existence?

Many of his most striking arguments and polemics came from an awareness of the intermingling of sociology and philosophy, most famously in the marvellous initial assault in Words and Things (1959) on the social complacency that underlay the hegemony of linguistic philosophy. Still, it makes sense here to distinguish the two areas for a moment. For it may well be that Gellner’s philosophic achievements are ultimately more convincing than his account of our social circumstances, despite the brilliance of the varied set-pieces involved in the latter.

Legitimation of Belief (1974) still stands out against the intellectual current because of its defence of critical monism against pluralism. If the book itself offers an account of the way in which empiricism and mechanism work to select information, his full position was only revealed in companion essays.footnote1 The brilliance of his argumentation derived from embracing, rather than trying to hide from, the criticism that cognitive strategies are not neutral because ontologically pure, but rather social conventions. Gellner’s point was that empiricism can be, should be and indeed is best defended once this is taken into account. As a cognitive ethic it has on its side an effectiveness which sets it far above its rivals. Positivism is thus best for Hegelian reasons.

This takes us more generally to Gellner’s liberalism. This was made particularly fruitful in being aware of enemies on two sides. On the one hand, Gellner was a superb critic of monolithic belief systems, whose pretensions and ambiguities he deflated continually and effectively. But this did not make him an unqualified defender of tolerance, prepared to endorse Pascal’s view that truth is just different on the other side of the Pyrenees. He found relativism of this sort morally repulsive because it was hypocritical: some guarantee was needed that tolerance was being extended only to those prepared to be tolerant themselves. Gellner thus insisted that certain minimal shared rules are necessary within which choice can then hold sway. To hold such a position is to entertain an ambivalence—wholly honourable, in my view—that was certainly present in his work. On the one hand, his work can be seen as telling us about our world, so that it can then be better defended against such enemies as fascism. On the other hand, the attempt to provide criteria by means of which to choose between the social worlds provided by modern ideologies is a sign of a continued search for universalism, for reasons that will appeal to all human beings regardless of context.

Of course, Gellner’s dislike of relativism was based quite as much upon the way in which he felt that it could distort the understanding of our social condition. Here his arguments against idealism, against any uncritical acceptance of the view that meaning makes the world go round, retain enormous force, for all that they did not sweep everything before them. At a general level, he was surely right to insist that concepts are often derived from other, more basic social processes: military victories and revolutions obviously have the capacity to change styles of thought, as too do changes in modes of production. More specifically, the insistence on the necessity and possibility for causal analysis in social and historical understanding rested on two sets of observations. On the one hand, belief systems were not seamless wonders, possessed of instructions as to how every facet of life should be lived. This is made particularly clear in his classic monograph on Saints of the Atlas (1969), particularly amusing sections of which see Gellner asking tribesmen questions derived from Wittgenstein as to the completeness and cogency of their system of concepts. The realization that belief systems are loose and baggy monsters, replete with options, brings causal analysis back in since it becomes necessary to ask about the circumstances which lead to particular sections of a belief system gaining appeal for particular social actors. On the other hand, Gellner resolutely insisted that certain universal physical properties underlie the practice of social inquiry. We know about the nature of beliefs in adoption, say, precisely because we have a physical model of kinship at the back of our mind.