  The Fall of 1872 brought two great tragedies to the Duhem family: a diphtheria epidemic killed Pierre’s younger sister Antoinette and his recently born brother Jean, leaving only Pierre and Antoinette’s twin sister Marie. Pierre continued his education (as demi-pensionnaire) at a Catholic school, the Collège Stanislas in Paris, in 1872 and for the next ten years. The mature Duhem recalled his college days as most formative. In particular, he singled out his science teacher as an important influence: