Edited by Daniel Lerner, with John G. Kemeny, Victor F. Weisskopf, S. S. Stevens, Walter A. Rosenblith, Harold D. Lasswell, Vassily Leontief, and J. J. Spengler Eight specialists explore the perennial dialectic of quantity and quality as it relates to basic methodological issues in contemporary mathematics, physics, psychophysics, neur ophysiology, politics, economics and economic history. Their explorations reveal that the ancient dichotomy between two mutually exclusive categories is today regarded as a "creative tension" between reciprocal ways of knowing. While the mechanistic and quantitative universe of the 19th century has vanished, contemporary scientific concern for quality does not simply reinforce the pre-scientific epistemology of an earlier era. Rather, the modern synthesis seeks to reshape more productively two components of knowledge that can no longer be maintained in dialectical opposition.