We live, so it is said, in a "modern" world different in its characteristic social structures and mentalities from what went before. Yet the nature of "modernity" and the reasons for social transition from "past" to "present" continue to be matters of profound interpretative disagreement. Such questions have, of course, been richly and provocatively contested within a major tradition of scholarship, linking figures such as Adam Smith, Karl Marx and Max Weber with current practitioners of historical sociology, development economics and social history. Recent landmarks in this debate include studies by Fernand Braudel (1967, 1979), Perry Anderson (1974a, 1974b) and Immanuel Wallerstein (1974, 1980).