Columbia subject headings:
Harvard subject headings:
Tolkien, J. R. R. (John Ronald Reuel), 1892-1973--Criticism and interpretation.
Tolkien, J. R. R. (John Ronald Reuel), 1892-1973--Philosophy.
Tolkien, J. R. R. (John Ronald Reuel), 1892-1973--Views on good and evil.
Princeton subject headings:
Ethics in literature.
Tolkien, J. R. R. (John Ronald Reuel), 1892-1973--Criticism and interpretation.