This book aims to explain the self as understood decades ago and its evolution in the time of postmodernism. Approaching it primarily from a sociological perspective, while incorporating insights from psychology and philosophy, it portrays the modern self as a unitary, coherent, unified subject created in the time of modernity, which during postmodernism has evolved into a fluid, decentralized, and fragmented subject with increasingly independent multiple identities. The creation of the modern self has been influenced by individualization, rationalization, and power. Each factor is explored in a separate chapter, detailing its impact on the development of the modern Cartesian self. The authors draw on the theories of Goffman, Bauman, and Baudrillard to illustrate the changing nature of the self, viewing it as a performer, a fluid entity, and a simulacrum. While Goffman is not strictly a postmodern author, his ideas foreshadow postmodernism, particularly regarding the transformation of the self. Bauman and Baudrillard, as key figures in postmodern thought, provide valuable insights into this transformation of the self in contemporary times. The book uniquely connects two time periods in which the self evolves, arguing that social factors influence its changing characteristics. As these social factors shift over time, so does the self. Key aspects of the self and its evolution are examined through an original, multidimensional approach that spans a longer time interval.