Throughout the twentieth century critical and popular opinion regarded Shakespeare's tragedies as his highest achievement; there is no sign that their pre-eminence will be modified in the twenty-first. In a largely secular world they have been invested with the status of secular scripture, often treated with reverence as spiritual masterpieces of transcendent literary art rather than as great plays written about four hundred years ago. The texts have sometimes appeared like sacred objects, especially in collected editions. Certainly the discussion of individual plays (sympathetic or hostile) has often been conducted as if the text of each were definitively established, canonically determined, and available for exegesis.

However, such is not the case. The notion of a single authentic text belongs to the tradition of reading plays rather than that of performing them in the playhouse, where performance admits variation. The texts of Shakespeare’s tragedies, as of all of his plays, are unstable. The modern editions that we study are derived from documents of doubtful origin and imperfect execution about which there is less external evidence than we desire. Those early documents are constantly re-edited in the light of new knowledge, new theoretical concerns, and new hypotheses.