Arnaut Daniel (; fl. 1180–1200) was an Occitan troubadour of the 12th century, praised by Dante as "the best smith" (miglior fabbro) and called a "grand master of love" (gran maestro d'amore) by Petrarch. In the 20th century he was lauded by Ezra Pound in The Spirit of Romance (1910) as the greatest poet to have ever lived. Life According to one biography, Daniel was born of a noble family at the castle of Ribérac in Périgord; however, the scant contemporary sources point to him being a jester with pernicious economic troubles: Raimon de Durfort calls him "a student, ruined by dice and shut-the-box". Work and style The dominant characteristic of Daniel's poetry is an extreme obscurity of thought and expression, a style called trobar clus ('hermetic verse'). He belonged to one school of troubadour poets that sought to make their meanings difficult to understand through the use of unfamiliar words and expressions, enigmatical allusions, complicated meters and uncommon rhyme schemes. Daniel further invented a form of stanza in which no lines rhymed with each other, finding their rhymes only in the corresponding line of the next stanza. Daniel was the inventor of the sestina, a song of six stanzas of six lines each, with the same end words repeated in every stanza, though arranged in a different and intricate order. Henry Wadsworth Longfellow claims he was also the author of the metrical romance of Lancillotto, or Launcelot of the Lake, but this claim is completely unsubstantiated; Dante's reference to Daniel as the author of prose di romanzi ("proses of romance") remains, therefore, a mystery. There are sixteen extant lyrics of Arnaut Daniel only one of which can be accurately dated, to 1181. Of the sixteen there is music for at least one of them, but it was composed at least a century after the poet's death by an anonymous author. No original melody has survived. Legacy Daniel's attempt to avoid simple and commonplace expressions in favor of striving for newer and more subtle effects found an admirer in Dante who would imitate the sestina's form in more than one song. Petrarch also wrote several sestinas as the form later gained popularity with Italian poets. In Dante's Divine Comedy, Arnaut Daniel appears as a character doing penance in Purgatory for lust. He responds in Old Occitan to the narrator's question about who he is: Tan m'abellis vostre cortes deman, qu'ieu