Comments in this direction havealso been made by the physicist David Ruelle, acolleague of Grothendieck’s at the IHES: After asuperhuman effort, Grothendieck had to admitthat he would never be able to complete the oeuvrehe had begun. It was as if he had set his mind onbuilding a cathedral with his own hands. When thewalls were two meters high, he had to stop.