Lessons in "pure visibility" (reine Sichtbarkeit): Victor Hammer's correspondence with Heinrich Schenker

In 1924-25 Heinrich Schenker attended a number of sittings for his famous mezzotint portrait by the artist Victor Hammer (1882-1967). It was during this time that they began an ongoing exchange of ideas concerning the relations between art theory and music theory. These communications culminated in 1926 when Hammer mailed to Schenker four postcards of Renaissance paintings on which he affixed transparent overlays with notes and tracings. I interpret Hammer's annotations to reveal that Hammer and Schenker's theories find common ground in the nineteenth-century aesthetic theories of "pure visibility" (reine Sichtbarkeit) developed by Conrad Fiedler and Adolf von Hildebrand.