As play concerned with trans-generational memory, The Piano Lesson is appropriately haunted by ghosts: the ghost of Sutter, the Ghosts of the Yellow Dog, the ghosts of the ancestors, and, in a less supernatural sense, those of Crawley and Cleotha. This profusion of ghosts reveals a blending of Christian, folk/superstitious, and African mystical traditions. For example, the final exorcism or Avery's description of the Ghosts of the Yellow Dog as the "hand of God."
The more supernatural ghosts wage war in a larger struggle between the Sutters and Charles—allegorically, the whites and blacks—across the generations. These ghosts primarily concern themselves with vengeance: Sutter returns to avenge his murder and reclaim the piano, and thus the Charles family; the Ghosts of the Yellow Dog avenge their own murder by murdering Sutter; these ghosts met their end when living in Boy Charles's attempt to avenge the ancestors. In some sense, their insistence on revenge makes it impossible for the living to mourn them, since their debts cannot be erased. In contrast, Crawley and Cleotha are ghosts their survivors are attempting to mourn, and have pasts their survivors are attempting to work through. Berniece in particular appears to begin to work through her grief over Crawley in her seduction by Lymon.
Throughout the play, a number of characters address the dead across the grave, the speech of the dead becoming a central vehicle by which the living assume their legacy. Often this call takes place in music, the call structuring the traditional song also serving as the call across the grave. Wining Boy, for example, engages in a direct dialogue with the Ghosts of the Yellow Dog at a railroad junction, finding new strength and fortune in their voices. Berniece, distinguishes herself far more powerfully as the family's priestess, her song calling the dead into the present and connecting the living to their place of origin. She assumes this role in childhood, playing the piano so her mother can hear her dead father speak. In the present, she returns to the piano as supplicant, forcefully imploring the ancestors to assist in the exorcism.
Examples of African American musical traditions in The Piano Lesson are abundant, such as the work song, the traveling song, the blues, and the boogie- woogie. As Wilson has noted, the trope of music and, as the title suggests, the musical lesson allegorizes the confrontation with one's historical legacy and attempt to understand how one should use their past. Almost pedagogical in their intent, the numerous musical interludes in the play serve to document particular moments in black history. Key examples include the men's song about the Parchman Prison Farm or Doaker's railroad song. The latter consists largely of place names that trace a travel route through the South. More subtly, the play's epigraph, a verse from Skip James, serves by dint of a double entendre as a cryptogram, or a piece of writing in secret characters, for the Charles family's history: "Gin my cotton/ Sell my seed/ Buy my baby" The echoes of the slavery and its traffic in human flesh are inescapable, the song encoding the traumatic legacies at hand. Whether as document or cryptogram, music becomes a "lesson" in the African American legacy.
At the heart of The Piano Lesson is a sibling couple who represent two attitudes toward the family legacy. These attitudes are explicitly gendered, articulated in the name of the father, in the case of Boy Willie, and the mother, in the case of Berniece. In selling the piano, Boy Willie imagines himself as acting as his father might have and winning the property he could only work to the benefit of others. In doing so, he leaves his mark on the world, just as Boy Charles did with his theft. Against her brother, Berniece will conjure the image of Mama Ola, mournfully tending to the piano until the day she died. Like her mother, Berniece figures as the guardian of the family's past sufferings.
In the play's final scene, Boy Willie declares that he wants to leave his mark in the world. He would do so by buying Sutter's land. The trope of the mark invokes a larger paternal tradition. As Willie notes in the same scene, Boy Charles left his "mark" on the calendar the day he stole the piano, providing the family with its own Day of Independence. Willie Boy literally left his mark on the piano, inscribing the family's history in the language most readily available to him. The mark on time—a certain "making" of history—is crucial to the preservation and continuation of the family's legacy.