<p>This paper introduces Existential Parallelism, a work of theoretical integration designed to provide a new synthesis for understanding the proliferation of inauthentic living in late modernity. We argue that contemporary structural conditions, characterized by neoliberal rationality and the cultural burden of perpetual self-construction, foster a widespread “existential vacuum.” Theorized as a systemic societal condition, this vacuum channels individuals toward “substitute attachments”, market-driven replacements for authentic sources of meaning, such as genuine community and value-based action. These substitutes (e.g., consumerism, ideological rigidity) simulate purpose while deepening alienation. We posit that cognitive biases function as crucial stabilizing mechanisms, sustaining the parallel life paths that mimic authenticity but ultimately diverge from it. By integrating knowledge from classical social theory (including the Frankfurt School), existential philosophy, and cognitive science, this framework reinterprets crises like political polarization and burnout as predictable outcomes of a social order that commodifies meaning. This paper contributes to a more universal social science not only by offering a synthesized model for critique but also by outlining potential pathways toward authenticity, thus addressing both the diagnosis of and potential remedies for this contemporary crisis of meaning.</p>