Book excerpt: 2012 Reprint of 1957 Edition. Exact facsimile of the original edition, not reproduced with Optical Recognition Software. Tjalling Charles Koopmans (1910 - 1985) was the joint winner, with Leonid Kantorovich, of the 1975 Nobel Memorial Prize in Economic Sciences. In 1944 Koopmans joined the Cowles Commission for Research in Economics at the University of Chicago, where he extended his technique to a wide variety of economic problems. When the commission was relocated to Yale University in 1955, Koopmans moved with it, becoming professor of economics at Yale. He wrote a widely read book on the methodology of economic analysis, "Three Essays on the State of Economic Science" in 1957. Essays are: Allocation of Resources and the Price System The Construction of Economic Knowledge The Interaction of Tools and Problems in Economics