Thoreau checks out Dramas and Other Poems of the Abbé Pietro Metastasio translated by John Hoole, volume 1 from Harvard College Library (Companion to Thoreau’s Correspondence, 287).
Thoreau also attends a meeting of the Institute of 1770, in which the topic “Are the refined and cultivated happier in general than the ignorant?” is debated (The Transcendentalists and Minerva, 1:82).