On poetry and geometric truth . . .

          On poetry and geometric truth
          And their high privilege of lasting life,
          From all internal injury exempt,
          I mused; upon these chiefly:  and at length,
          My senses yielding to the sultry air,
          Sleep seized me, and I passed into a dream.

                                                  William Wordsworth (1770-1850)
                                                  from The Prelude, Book 5