PRIGOGINE, ILYA (1917–2003), mathematician and Nobel laureate in chemistry. Born in Moscow, Prigogine moved with his family to Belgium at the age of four. His father was a chemist and Prigonine, who had a lifelong interest in music and history, obtained his doctorate in chemistry in 1947 at the Free University of Brussels, whose staff he then joined. However, his broad intellectual interests profoundly influenced the direction of his scientific research. From 1959 to 2003, he was director of the International Solvay Institutes in Brussels and in 1967 he founded Ilya Prigogine Center for Studies in Mathematics and Complex Systems at the University of Texas at Austin, Texas. When he started his life's work, conventional attitudes were based on the Second Law of Thermodynamics, which states that heat can never pass spontaneously from a colder to a hotter body, with the inference that energy transfer is unidirectional and all natural processes are irreversible. Prigigone and his associates used physical chemical experiments and mathematical modeling to understand the basis of stability in chemical reactions and biological systems. He refined the earlier concept of entropy, a measure of disorder in a system, with the theory of dissipation, that is, the regulated fluctuations which promote stability in the face of irreversible change. His theoretical and mathematical formulation of "dissipative structures" created by irreversible processes led to the award of the Nobel Prize in 1977. In his later years Prigogine became increasingly concerned with applying novel thermodynamic principles to the complexities of human biology and even human behavior. A natural extension of his interests was his concern for the potentially disastrous impact of human activities on the environment.