A pleasing permutation of lines -- the Villanelle

     A villanelle is a 19-line French verse form -- with lines divided into five three-line stanzas and a final quatrain -- a poem in which the first and third lines each appear four times.  This thoughtful repetition of lines, each time in a somewhat different context, is very pleasing -- and reminds me of the varied situations in which many mathematical models also are effective
     Well-known villanelles include “Do Not Go Gentle into That Good Night” by Dylan Thomas, and Elizabeth Bishop’s “One Art.” (And here is a link to this blog's offerings of villanelles.)   Below are the opening stanzas of a fine villanelle by Emily Grosholz; the entire poem is included in an article in The Mathematical Intelligencer, "Figures of Speech and Figures of Thought" (available here).  The article -- written by Emily Rolfe Grosholz and Edward Rothstein -- is based on an interview of Grosholz at New York City's Poets House and celebrates her book Great Circles -- The Transits of Mathematics and Poetry (Springer, 2018).  

from  Holding Pattern     by Emily Rolfe Grosholz   

        We can't remember half of what we know. 
        They hug each other and then turn away.
        One thinks in silence, never let me go.

        The sky above the airport glints with snow
        That melts beneath the laws it must obey.
        We can't remember half of what we know.  
                 .  .  .

Grosholz's complete poem is available here; for more villanelles, go here or here.