Knowledge that Transforms

casual empiricism, invalid use of inverse probability, introduction of factors external to the theoretical system, and the use of only some of the implications of a formal model that has others that are unrealistic. . . . The basic sources of the defects in Lange's theoretical analysis are the emphasis on formal structure, the attempt to generalize without first specifying in detail the facts to be generalized, and the failure to recognize that the ultimate test of the validity of a theory is not conformity to the canons of formal logic but the ability to deduce facts that have not yet been observed, that are capable of being contradicted by observation, that subsequent observation does not contradict. In consequence, these defects are found in much economic theorizing that is not taxonomic in character. They are, however, especially likely to arise when the taxonomic approach is adopted, as their presence in the writings of saable and careful a theorist as Lange testifies. (Friedman 1946, p. 631) Shortly after the publication of the piece on Lange, Friedman received a probing letter from Edwin Bidwell Wilson. That letter, Friedman's reply, and a second letter of Wilson's are reprinted below. E. B. Wilson (1879-1964) was a scientific generalist of a type that has always been uncommon, and is becoming unknown. Wilson studied under the mathematical physicist J. Willard Gibbs, and his publication of Gibbs' notes on vector analysis and a text of his own on advanced calculus had a great impact upon education in advanced mathematics in the early part of this century. Wilson held faculty positions in mathematics at Yale and mathematics and physics at M.I.T. before he moved in 1922 from being the Chairman of Physics at M.I.T. to Harvard to be Professor of Vital Statistics in the Harvard School of Public Health, a position he held until his retirement. In 1914 he was appointed Managing Editor of the Proceedings of the National Academy of Sciences, a post he held for fifty years, until his death. In 1929 he served as President of the American Statistical

This paper reviews and interprets from an economic perspective the demographic trends in the U.S. since the turn of the century. The primary focus will be upon the interplay between the fertility and labor force participation of women and how they may be interpreted within simple economic models....We will begin by stating what economic demography is and why careful analytic methods are needed. Section II provides a brief demographic history of the U.S. Section III describes the major economic theories of fertility and Section IV discusses the empirical performance of these theories. Section V discusses the linkages between fertility and the size of the labor force and Section VI concludes. (EXCERPT)

Our data collection and database assembly efforts were assisted by John P. Sophocleus, Mark Gwartney, Michele Butler, and Scott Ralston. We received extremely valuable computer programming assistance from Jon Brunson and Edward Novak. Constructive comments were receivedfrom two anonymous reviewers. Financial supportfrom the Faculty Development Committee at Salisbury State University is gratefully acknowledged.

BY MOST CRITERIA the arts comprise a significant area of economic activity. In 1990, American consumers spent $5 billion on admissions to theater, opera, galleries, and other nonprofit arts events (more than on admissions to spectator sports), $4.1 billion on movie admissions, and $17.6 billion on books. Because of difficulties in defining boundaries around the arts industry, statistics on its contribution to GDP are problematical, but available data suggest that the arts (theater, music, opera, dance, visual arts, crafts, literature, community, and folk arts) account for a little under one percent of the United States GDP and a little over one percent of the civilian labor force. If the net is cast somewhat wider, defining the cultural industries as including the arts, motion pictures, radio and television, and printing and publishing, an aggregate value of output can be measured for 1988 of about $130 billion or 2.5 percent of GDP (National Endowment for the Arts 1992). Likewise, support for the arts and culture in the U. S. through government and voluntary contributions amounts to a significant annual commitment of funds. Combined federal, state, and local government expenditure on the arts and museums in 1987 amounted to about $0.8 billion, and in 1990, 6.4 percent of charitable giving was channeled to arts, culture, and the humanities, yielding a total level of voluntary contributions in these areas of $7.9 billion in that year. Private markets in the arts, too, are of significant size. Looking at the international art trade, for example, we can note that the worldwide net sales of the two major art auction houses (Christie's and Sotheby's) amounted to $6.6 billion in 1989-90.1 Yet, despite the fact that production and consumption of art have been elements of human activity for longer than most of the phenomena that have en-