Sonnet 18

“Shall I compare thee to a summer’s day?” is a poem in the form of a Petrarchan sonnet—that is, a 14-line rhyming ode. While Petrarch’s odes to a real or imaginary “Laura” focused only on his obsessive idealization of a woman whom he could not have, and probably only desired expressly for her unattainability, Shakespeare’s ode has an unnamed object. It is also possible that the poem is less focused on an actual person than it is on a feeling or concept.

Further, as earlier noted, the form of the sonnets differs between Petrarch and Shakespeare. The former form is arranged as an octave (eight lines) and a sextet (six lines) with an ABBA-ABBA-CDCDCD or CDEEDE rhyme scheme, while the latter is often arranged as three quatrains (four lines apiece) and a concluding couplet (two lines) with an ABAB-CDCD-EFEF-GG rhyme scheme. This arrangement has—at least in part—to do with the language in which the poems were written as rhymes differ in varying languages.

The Shakespearean, or Elizabethan, sonnet was more intellectually inspired than the sonnets—from both Italy and France—preceding it. Both Petrarch’s and Shakespeare’s forms include a “turn,” which sheds new light on the central theme of the poem or shifts the focus in a way the reader may not have expected. This turn comes at different points in the two forms. In “Sonnet 18,” Shakespeare uses both rhyme and anaphora—repetition—at the beginning of Lines 13 and 14, reiterating the theme of eternality in contrast to both the brevity of summer and the short-lived nature of passionate affairs.