The "infrathin" was Marcel Duchamp's playful name for the most minute shade of difference: that between the report of a gunshot and the appearance of the bullet hole, or between two objects in a series made from the same mold. "Eat" is not the same thing as "ate." The poetic, Marjorie Perloff suggests, can best be understood as the language of infrathin. For in poetry, whether in verse or prose, words and phrases that are seemingly unrelated in ordinary discourse are realigned by means of sound, visual layout, etymology, grammar, and construction so as to "make it new." In her revisionist "micropoetics," Perloff draws primarily on major modernist poets from Stein and Yeats to Beckett, suggesting that the usual emphasis on what this or that poem is "about," does not do justice to its infrathin possibilities. From Goethe's eight-line "Wanderer's Night Song" to Eliot's Four Quartets, to the minimalist lyric of Rae Armantrout, Infrathin is designed to challenge our current habits of reading and to answer the central question: what is it that makes poetry poetry?