Ilya Prigogine, winner of the Nobel Prize in 1977 for his work on the thermodynamics of non-equilibrium systems, makes his ideas accessible to a wide audience in this book, which has engendered massive debate in Europe and America. He and his colleague, Isabelle Stengers, show how the two great themes of classic science, order and chaos, which coexisted uneasily for centuries, are being reconciled in a new and unexpected synthesis.