A central question concerns what Wrigley (1981a, p. 216) has referred to as the 'logical status of population history', that is whether population change is relegated to the role of a dependent variable or whether population trends themselves may be considered to influence wider social and economic change. The Annalistes would certainly argue for demography as an integral, defining feature of different systems of material life and would attach less importance to the primacy of the economic as sugg"ested by their Marxist critics. Thus, it may be argued that while the discovery of sources and of techniques for their analysis is crucial, equally important is 'a new appreciation of the significance of the interplay of the forces which govern the population characteristics of a community. Just as the rise of economic history as a subject for investigation testifies to the r.ecognition of the central importance of production to a society, so the parallel develop-
ment of population history reflects a similar recognition of the significance of reproduction' (Wrigley, 1981a, p. 221). An appreciation of the reciprocal relationship between production and reproduction has been made possible by recent research on marriage and fertility and has been reflected in the search for general theoretical statements.