Axiomatic Foundation of Narrative Legitimacy

This work proposes an axiomatic foundation for narrative legitimacy by identifying a minimal condition under which narrative outcomes are perceived as “earned” rather than arbitrary or contrived. Drawing on research in cognitive psychology, social psychology, developmental psychology, neuroscience, evolutionary theory, and narratology, the paper formulates a Legitimacy Axiom: an outcome is legitimate when at least one cognitive agent—reader or character—recognizes that the total cost in constraints, effort, time, and sacrifice exceeds the magnitude of the effect. The paper distinguishes external causal coherence (primarily evaluated by readers) from internal psychological necessity (experienced by characters), showing how legitimacy emerges when these two cognitive layers converge. It further situates the axiom within a broader theoretical framework by examining developmental differences in cost perception, cultural modulation of cost components, genre-specific weighting of values, and the layered structure of situational, relational, symbolic, and civilizational costs. Several appendices extend the theoretical model: developmental adjustment of cost perception (Appendix A), cultural parameterization (Appendix B), genre-specific modulation (Appendix C), value-layer mapping (Appendix D), edge-case legitimacy patterns (Appendix E), and post-hoc cost augmentation as a narrative repair strategy (Appendix F). Together, these analyses demonstrate that the inequality Effect < Cost provides a universal structural principle whose parameters vary across audiences, cultures, and narrative forms. The axiomatic approach offers a unified framework for narrative analysis, cross-cultural comparison, and computational story generation. It clarifies the cognitive mechanisms underlying narrative legitimacy and provides a principled alternative to informal notions of “plot convenience,” enabling both theoretical insight and practical application in human and machine-authored storytelling.