With the publication of her first book, Against Interpretation, in 1966, Susan Sontag placed herself at the forefront of an era of cultural and political transformation. "What is important now," she wrote, "is to recover our senses ... In place of a hermeneutics we need an erotics of art." She would remain a catalyzing presence, whether writing about camp sensibility, the films of Jean-Luc Godard and Alain Resnais, her experiences as a traveler to...