The IHÉS at Forty

N ot far outside Paris, in a small village, along a busy road, there is a gate leading into a park. The sound of the traffic dissipates as one follows the footpath. The trees are abundant enough to give the impression that one is simply walking through a serene wood, which has a slight incline that amplifies the rustle of the breeze through the treetops. But soon one reaches a small parking lot, and beyond it a summer house that has been fitted with windows and turned into a library. Next to the summer house there is a nondescript twostory building, and down a lawn of trimmed grass, a low one-story building. This is no ordinary park. It is the Bois-Marie, grounds of one of the world’s leading research institutes in mathematics, the Institut des Hautes Études Scientifiques (IHÉS). Now forty years old, the IHÉS has spent nearly its entire lifetime in the Bois-Marie, in the Paris suburb of Bures-sur-Yvette. A special event was held last October to celebrate four decades of research at the IHÉS. Over this period, the institute has provided mathematicians with an idyllic, and in many ways ideal, setting for research. The story of the IHÉS, as befits its French heritage, is a story with a little of everything—romance, madness, tragedy, as well as triumphal intellectual achievements. It is also the story of a small, hardy institute that has survived, despite perpetual financial uncertainties, to become home to an illustrious permanent faculty and a major visiting center for researchers from all over the world.