"Models and Realities": An Introduction‪.‬

This is the first of a series of symposia we are organizing in the pages of the Pakistan Development Review to fix our gaze on the twilight zone lying between the theory and the practice of development economics. In the Autumn of 1979--I must confess, not without a tinge of autumnal depression--I had addressed letters to about 50 scholars working in this general area announcing that "it is proposed to bring out symposium issues of the Pakistan Development Review focusing on the State of Development Economics, which in the opinion of many has not yet attained its 'steady-state'. It is, therefore, essential to have a second (or nth!) look at the state of the art in the general area of development economics, not only to satisfy our academic appetite and to whet it a little bit more, but also to provide proper guidelines for policy formulation". Those who responded to this request did so enthusiastically, supporting the general idea expressed in the letter. Considering the exceedingly busy schedule that economists keep these days, the outcome of my appeal has been gratifying--even though the 'utility function', appropriately discounted by a 'time-paucity' factor, has still not been optimized! On the basis of the contributions already received as well as of those confidently expected soon, we should be able to bring out at least three special symposium issues, devoted to the "State of Development Economics: Models and Realities". The present issue includes papers by outstanding scholars like Jan Tinbergen, Sukhamoy Chakravarty, Paul Streeten, Anthony Bottomley, Pan Yotoponlos and Amit Bhaduri. The coming issues of the Pakistan Development Review will include longer papers on some of the problems touched upon in the present collection and on such basic questions as the choice of techniques, trade policy, economic-demographic modelling, urban-rural and inter. national migrations, etc. The contributions by Tinbergen, Chakravarty and Bhaduri, included in the present issue, make it quite clear that growth models are--in fact, have been--highly relevant for development planning. One of the contributions of growth theory has been that it has provided us with an "analytic filing system", a la Friedman, or with a "language", promoting systematic and organized thinking, a la Marshall. However, if its utility were to rest mainly on its educative role, then this would not be enough justification for the economist's insistence that the policy-makers did need growth theory more than they normally do-that is not at all! For having succumbed to the economist's logic, what should the 'madman in authority' make of the endless debate about one 'filing system' being superior to another? And if it is asserted that for educative purposes it does not matter which version is superior, then the 'filing system' ceases to be even of any epistemological interest. The real worth of growth theory, as Chakravarty shows, is that it represents a body of suggestive hypotheses which help us not only to understand the highly complex reality of economic growth but also to make valid 'predictions' about the entire growth path, once the initial conditions are specified. It is in this context that even such seemingly esoteric concepts of growth economics as 'steady-state' and the turnpike theorems provide important guidelines to policy makers in their task of charting out the best possible strategy for development--or, in the somewhat opaque language of the growth theorists, in delineating optimal trajectories of consumption, investment and output. A more direct application of the growth models is exemplified by the use of the two-sector, 'closed' Mahalanobis-Fel'dman model, involving non-shiftable capital stock, to determine the policy choice about the size of the restraints to be imposed on 'initial' consumption. Such a conceptualization of the development process has dictated a strategy which puts a premium, at the initial stages of planning, on a heavy investment in