In his office in Paris’s National Assembly, Cédric Villani opens a parcel: it contains a metallic spider. “Lovely,” he says, putting it on a shelf, where a collection of spider-shaped objects sits ...

It’s a cold, early February evening in Paris, and the Trianon theatre is jam-packed. About a thousand men and women of all ages have raucously filled the orchestra pit and balconies, not intimidated ...

Cédric Villani’s arrival, one afternoon last May, at a small café off the Champs-Élysées drew glances from a good fraction of the late-lunch crowd. His shoulder-length hair was parted almost ...