In Landscape with Moving Figures, Ms. Jacobs reflects on the art form during the ten-year period from 1994 to 2004 when dancers, choreographers and dance lovers were challenged by AIDS and the loss of the last of the founding giants of American dance. Grounded by her vast knowledge of the form and guided by her own sensitive gifts of perception, Ms. Jacobs ponders the very purpose of the art as she encounters it in landmark performances of the decade...