The capacity for personal isolation is as critical to psychological health as is the capacity for object relatedness. In this paper, the notion of personal isolation is expanded to include a form of isolation in which the infant replaces the mother-as-environment with his own sensation matrix. This form of experience is not conceived of as a phase or stage of development prior to object relatedness; rather, it is viewed as an ongoing facet of all human experience that serves as a buffer against the continual strain of being alive in the world of human beings. The understanding of this primitive dimension of personal isolation provides a way of thinking about the differences between the elaboration of universal “autistic-contiguous” forms of experience and the development of pathological autism.