Dedication

To my father, François Crouzet who, all of a sudden, on a day of despair, recited the opening lines of Dante's Divine Comedy (Paradiso, Canto 1 (1–3)):

La gloria di colui che tutto move per l’universo penetra,

e risplende in una parte più e meno altrove.

His glory, by whose might all things are moved,

Pierces the universe, and in one part

Sheds more resplendence, elsewhere less.6

Note