Claude Berge: 5.6.1926-30.6.2002

The departure of Claude Berge leaves a painful void in many of our lives. He enchanted people around him with his multiple talents, his great erudition in diverse domains, his sense of humour, his modesty, his love of life. Although primarily a combinatorist, Berge made a lasting mark on other subjects with his early mathematical work. His treatise on game theory [2] introduced an alternative to the Nash equilibrium, which has become known as the Berge equilibrium [1, 28, 32]. His book on topological spaces [4] introduced a theorem which has become known as the Berge maximum theorem and is considered one of the most useful tools in economic theory [31, 35, 39]. Up to the 1950’s, many mathematicians considered combinatorics and graph theory somewhat disreputable. Berge did a lot to change this perception. His 1958 monograph on graph theory [3] was translated into English, Russian, Spanish, Romanian, and Chinese within five years. As Daniel Dugué [26] put it: