Shakespeare Reference in The Witch’s Workbook

Ann Grammary’s The Witch’s Workbook contains a reference to Hamlet. In the book’s introduction, Grammary writes, “There are more things in heaven and on earth than are dreamt of in all our theologies” (p. xiv). That is a reference to Hamlet’s line, “There are more things in heaven and earth, Horatio/,Than are dreamt of in your philosophy.” The Witch’s Workbook was published in 1973.