It is well established by psychopathological research that disorders of self-experience are among the main features of schizophrenic prodromes in a pathogenetic sense. Disorders of the phenomenal self, as "lack of ipseity" (the vanishing of the feeling of being embedded in oneself and of distinctiveness between the self and the outer world) and "hyper-reflexivity" (the monitoring of one's own life entailing the tendency to objectify parts of one's own self in an outer space) are considered key phenomena of schizophrenic vulnerability. In this paper, I argue that the analyses of the disorders of phenomenal self catch only some dimensions of schizophrenic vulnerability, since they mainly focus on the pathological changes in subjective experience of an isolated self and disregard the fact that the self is not purely personal. Because our existence is fundamentally tied to a social existence, the feeling of one's own self and the sense of "reality" of an experience are products of intersubjectivity and not only a private process based on introspection or reflexivity in which one is engaged in an idiosyncratic way. Building on, and extending, contributions of the phenomenological tradition, I attempt to demonstrate that intuitive attunement is the basic prerequisite for establishing one's sense of "reality" (feeling familiarly related to one's environment) and for establishing one's sense of "ipseity" (the sense of existing as a subject of awareness). In the last part of the paper, I show the importance of the concepts "lack of attunement" and "antagonomia" (the rejection of conventional knowledge and intuitive attunement, experienced as dangerous sources of loss of individuality) to establish a comprehensive theory of schizophrenic vulnerability. I finally discuss the implications of this view for empirical research and clinical management of schizophrenic vulnerability.