A theory of technology : continuity and change in human development / Thomas R. DeGregori. DeGregori, Thomas R. Technology Social aspects. Technology Philosophy. T14.5 .D46 1985 338.926 DEG Includes indexes. Bibliography: p. 221-251. Ames, Iowa : Iowa State University Press, c1985. c1985. 1985 Text xiii, 263 p. ; eng