This article introduces the concept of the Codex of Authority, a juridical metaphor for the compiled rule that governs without reference to a legislator. In predictive societies, authority is no longer produced by political will but by syntactic form. From automated drafts of the EU’s AI Act to blockchain smart contracts, institutional norms emerge as self-sufficient codices where legitimacy resides in structure rather than origin. By analyzing this shift, the article proposes a framework for understanding how legal authority becomes executable, impersonal, and detached from interpretation. DOI Primary archive: https://doi.org/10.5281/zenodo.17026629 Secondary archive: https://doi.org/10.6084/m9.figshare.30025570 SSRN: Pending assignment (ETA: Q3 2025)