With School of the Arts, Mark Doty’s darkly graceful seventh collection, the poet reinvents his own voice at midlife, finding his way through a troubled passage. At once witty and disconsolate — formally inventive, acutely attentive, insistently alive — this is a book of fierce vulnerability that explores the ways in which we are educated by the implacable powers of time and desire in a world that constantly renews itself.