Music is pervasive in Shakespeare's plays. According to J. L. Styan (1988), approximately 32 plays and over 500 text passages make reference to music. The critic also notes that there are at least 300 musical stage directions found in Shakespeare's plays. Many scholars who comment on these instances discuss them in terms of Shakespeare's evident familiarity with classical and Neoplatonic views of the ethical or moral nature of music. As Catherine Dunn (1969) notes, these views were largely based on the musical theories of Greek philosophers, such as Pythagoras and Plato, and the sixth-century Roman philosopher and theologian Boethius. According to Boethius' theory, there are three branches of music: musica mundana, meaning the music of the spheres or cosmic harmony; musica humana, signifying the rapport between human body and soul or between individuals and society; and musica instrumentalis, the composition and performance of vocal and instrumental music. The first two represent theoretical or speculative music, while the third represents practical music—which may induce personal and social harmony, but which is also capable of corrupting human nature. Indeed, Puritan writers of the late sixteenth and early seventeenth centuries regarded theatrical music as dangerous because they believed it promoted carnal pleasure. Most modern critics agree that even though Shakespeare incorporated classical and Neoplatonic theories in his plays, he also questioned the value and power of music.
Most scholars emphasize the importance of analyzing the songs in Shakespeare's plays in terms of their dramatic context. Commentators frequently treat Shakespeare's songs not as interruptions or delays in the dramatic action, but as a means of enhancing characterization and narrative development. W. H. Auden (1962) evaluates the dramatic effects of the words and moods of various songs upon onstage listeners as well as on theatrical audiences. Auden points out that Shakespeare frequently turned what might have served as merely a musical interlude into an element of dramatic structure. Thelma N. Greenfield (1966) similarly suggests that Shakespeare succeeded in making music a part of the narrative by using it to delineate character and augment thematic development. Concentrating on the military and ceremonial music of Shakespeare's English histories and Troilus and Cressida, R. W. Ingram (1971) finds an increasingly complex integration of music into the general design of Shakespeare's plays as the dramatist's artistry matured. David Lindley (see Further Reading) argues that Shakespeare's use of music reflects competing philosophical views of its constructive and destructive powers. He calls particular attention to Shakespeare's treatment of the Puritan linkage of music with effeminacy and irrationality. Some late twentieth-century studies of Shakespeare's plays have focused on music's effects in performance. Styan, for example, emphasizes the way Shakespeare exploited the disparate musical and theatrical effects of string, brass, and wind instruments. He further contends that each song and each dance is artfully designed to control audience response to the dramatic action. Commenting on “the remarkable similarities between Shakespearean and operatic style,” Gary Schmidgall (1990) urges actors and audiences to be attuned to the sound as well as the sense of the blank verse, contending that attention to its melodies and cadences is essential to understanding and appreciating Shakespeare's dramaturgy.
When commentary turns from general or comparative analyses to the subject of individual works, The Tempest—frequently described as the most musical of Shakespeare's plays—receives more critical attention than any other. Theresa Coletti (1974) maintains that in this play, music is the means through which harmony emerges from disorder. Coletti also argues that the play serves as a medium for “suffering, learning, growth, and freedom.” By contrast, David Lindley (1984) calls attention to the abrupt and dissonant endings of the two masques in the play; he suggests that these discordant endings reflect Shakespeare's ambivalence toward the idea that music promotes human and social reconciliation. Lindley further contends that this ambivalence is related to the play's questioning of the efficacy and legitimacy of Prospero's art. Jacquelyn Fox-Good (1996) directly challenges what she describes as critics' “simplistic” identification of music with order—in this play as well as other Shakespearean works. She suggests that in The Tempest music is frequently subversive, employed by characters who have been relegated to the margins of society and who use songs to voice their grievances and protest their subjugation.
In an evaluation of Ophelia's songs in Act IV, scene v of Hamlet, Fox-Good (see Further Reading) again applies her arguments about the association of Shakespearean music with socially marginal characters. She concludes an intensive musical and literary analysis of these songs by suggesting that they represent the most expressive and rebellious aspects of Ophelia's madness. Leslie C. Dunn (1994) offers a comparable assessment of these songs, emphasizing the way their disruptiveness enhances the portrayal of Ophelia as a threat to patriarchal notions of social decorum. Indeed, the critic views the responses of the male characters who are on stage while Ophelia sings as a reflection of cultural anxiety not only about music but about female sexuality as well. In a 1995 essay, Dunn focuses on Lady Mortimer's song in Act III, scene i of Henry IV, Part 1, remarking on the contrast between this song's representation of domesticity and eroticism and the play's overwhelming concern with male power struggles. As with the songs of Ophelia and Desdemona, Dunn suggests, Lady Mortimer's Welsh tune underscores female powerlessness and marginality. Rosalind King (1987) contends that Desdemona's “willow song” in Act IV, scene ii of Othello functions as a harrowing expression of her confusion and helplessness in the face of the destruction of her harmonious marriage to Othello. King further calls attention to the distinction between private and public music in this tragedy, particularly the aubade at the beginning of Act III, scene i and the multiple effects of military music throughout the play.
Even a brief introduction to published commentary on Shakespeare's music would be incomplete without reference to Lorenzo's speech about music and harmony at the beginning of Act V, scene i of The Merchant of Venice. Greenfield offers a traditional reading of the passage, interpreting it as a Neoplatonic discourse, in lyrical form, on the correspondence between the music of the spheres and human virtue. She endorses the view that the moonlit night and the consort of viols that accompany these lines combine to present “a vision of human love and universal concord.” In sharp contrast, Marc Berley (2000) rejects the notion that Lorenzo's speech is a straightforward summary of standard theories of music, emphasizing instead its complex significance and Jessica's ambiguous response to it. He proposes that in this passage, Shakespeare mocked Neoplatonic musical theory and portrayed Lorenzo attempting to mislead Jessica through “false music.”