Meditative, comic, emotionally wrenching, steeped in both the natural world and the life of the mind, the poetry of A. R. Ammons is at once cosmic in scope and intimate in its moment-to-moment transformations. With his mastery of description and cadence, his roiling wit and fearless gaze, Ammons was a philosopher of the everyday who found surprise everywhere he looked. "He is often witty, sometimes bawdy," writes editor David Lehman, "on a perpetual...