Columbia subject headings:
Love.
Sex in art.
Wagner, Richard, 1813-1883--Aesthetics.
Harvard subject headings:
Wagner, Richard, 1813-1883--Political and social views.
Wagner, Richard, 1813-1883. Literary works. Selections. English
Wagner, Richard, 1813-1883. Operas.
Princeton subject headings:
Dance--Philosophy.
Wagner, Richard, 1813-1883. Literary works. Selections. English