growth could be considered in a timeless and spaceless context with every element, including man himself, neatly categorized and controlled, problems of economic growth and economic change would be considerably less vexing. But men and circumstances are not easily categorized or controlled; history does not follow a predictable course; nor is it inevitable. While production is a technical process, economic change is more an historical process of evolution than a theoretical or mechanical process of change (indeed, how many of our problems arise because we do think mechanistically). It may depend as much upon strength of will and good fortune, concepts not generally included in theoretical analyses, as anything else.7 Only in theory can mankind be viewed as "developing" collectively along a known path to a known goal. In reality each people is participant in and heir to its own unique historical experience. The experience of economic growth has been common to only a few. Perhaps the one thing we may be sure about is not growth, not decline, but change. American Economic Association, LXI (May, 1971), 53-62; F. H. Hahn, "Some Adjustment Problems," Econometrica, XXXVIII (January, 1970), 1-11. A technical view of man's actions in the world follows closely in the Cartesian tradition, which works very well when considering the properties of atoms or the movement of stars. In part, men's actions also are predictable, but only in given social and historical contexts, and then not entirely. When one extends the analysis to the predictability of changes in the contexts themselves, the problem becomes still more difficult. It is common prudence to look ahead, but who really can predict the future?