Bruno Fritsch, born in Prague in 1926, was Professor emeritus of Economics at the Swiss Federal Institute of Technology in Zurich. He was author, co-author and editor of more than twenty books. He collaborated for many years with Karl W. Deutsch on basic problems of Political Economy. One among several other results of this collaboration was the jointly written book on Reduction of Complexity (1980). The fourth enlarged and updated edition of Professor Fritsch’s most comprehensive book on “Mensch-Umwelt Wissen” (first edition 1990) was published in 1994. Prof. Fritsch held various appointments as visiting Professor of Economics e.g. in the College of Europe in Bruges (Belgium), in Harvard (Summer School), The Australian National University (ANU), the European University Institute in Florence (Italy) in the University of Sydney (Australia) etc. He was Fellow at the Institute for Advanced Study in Berlin (1982/83). From 1975-1985 he worked regularly during the period of 4 to 6 weeks per year at the Berlin Science Centre on invitation from Karl W. Deutsch.