‘Dialectic’, Alexander Herzen once wrote, ‘is the algebra of revolution.’ More often, though, its function has been alchemical: a source of incantations by which revolutionaries have transmuted defeats into victories – or at least into vindications of the ‘dialectical world-view’. This book is written in the belief that the best safeguard against such exploitation is to examine the notion of dialectic at its modern point of origin, in Hegel's theoretical philosophy. It operates there, I believe, as part of a thorough-going, consistently applied, conception of philosophical rationality, centred on the ‘speculative discourse’ of the Science of Logic. That previous commentators have failed to identify this conception has been due, as much as anything, to a concern to separate out an acceptable, independent ‘kernel’ from this original context. My own interpretation, however, can make no such claim; the rationality of Hegel's dialectic is, I shall argue, inextricably linked to Hegel's Absolute Idealism.

Before embarking on the interpretation which occupies the central chapters of the book, I offer, in Chapter 1, a more general account of the issues involved in the interpretation of philosophical texts; this will illuminate, I hope, my interpretative strategy. Subsequently, in Chapter 7, I discuss a modern philosopher, Theodor Adorno, whose work is based on a critical appropriation of Hegel. My aim is to illustrate, in the light of the interpretation previously developed, the way in which Hegel's categories continue to exercise a hold even outside their original context.