In his intensely physical acting, the nineteenth-century actor, Edwin Forrest, crafted a working-class theatrical aesthetic that imagined our existence not as drifting, but as ontologically between, an ontological third term distinct from both the mind-centered and the body-centered ontological paradigms. By recovering the way Forrest staged his own muscular—and white—body in his interpretation of Shakespeare’s Othello (1826) and in Bird’s The Gladiator (1831), this chapter argues that Forrest used the experience of his labored at, and laboring, body to perform this ontological betweenness as an alternative to the antebellum market’s alienation and regulation of working-class bodies. In staging the agency of white, working-class bodies against Black inagentic bodies on stage, Forrest’s performance of ontological betweenness “minded the body” by offering his adoring working-class audiences less alienated—but racially complicated—ways to perform their own material embodiment in the early nineteenth century.