This article queries how one type of human difference--alterity, the experience of multiple distinct consciousnesses, or "alters," by one person--is pathologized in American culture. This experience is inscribed as a mental illness, labeled now as dissociative identity disorder (DID) and formerly known as multiple personality disorder (MPD). In this analysis, the notion of the modernist subject or self as a linear, cohesive, unitary consciousness is challenged as a method of suppressing difference. Alternative language is proposed for talking about the self. Those who experience alterity can be said to experience polyvalent selves. If a singular self is commonplace, then polyvalent selves are queer, unusual, different, and worthy of study because such difference represents a creative and dynamic uncertainty that cannot be easily suppressed, explained, or interpreted away by modernist institutions and theories. Utilizing a postmodern and public pedagogy framework, the author analyzes cinematic texts that depicted alterity to identify messages in popular culture that might be disabling to adult learners who experience alterity. The films reviewed consistently depicted alters as distinct and separate entities who, despite inhabiting the same body, communicate with difficulty. They also usually depicted alterity as a diseased condition caused by trauma that must be remembered in order to heal a putatively shattered self.