IT SEEMS THAT MUSEUMS increasingly want exhibitions to speak about museums themselves—in order to justify their importance by reflecting the legitimacy of their history or to demonstrate their openness to forms and approaches they used to be able to assimilate with only the greatest difficulty, such as movement, the performative, or criticism. As part of this shift, institutions deeply desire the supposed challenge of exhibitions constructed around immaterial works—examples include “Voids” at the Centre Pompidou in Paris, the recent Marina Abramović retrospective at the Museum of Modern