Though ostensibly the story of an unknown heir to a dukedom in thirteenth-century Italy, Robert Browning's Sordello (1840) was considerably complicated by its philosophical meanderings. Tennyson reportly remarked that there were only two lines in the poem which he could understand, and both were lies: "Who will may hear Sordello's story told" and "Who would has heard Sordello's story told."
Browning himself was once asked by members of the London Poetry Society for an interpretation of a particularly confusing passage. After reading it through twice, Browning frowned, and shrugged his shoulders. "When I wrote that, God and I knew what it meant," he declared, "but now God alone knows!"