Reconsidering the Epistemological Foundations of Economic Analysis of Law in the Age of Artificial Intelligence: From Posnerian Efficiency to Algorithmic Rationality and the Transformation of Legal Teleology

This article reconsiders the epistemological foundations of the economic analysis of law in the context of artificial intelligence. It argues that AI reconfigures the core assumptions of law and economics under which these assumptions are operationalised. In classical frameworks, rationality functions as a simplifying device for modelling how individuals respond to legal rules. The increasing use of data-driven systems reshapes the informational and institutional environments within which such behaviour is analysed. The article examines how this transformation affects four central concepts: rationality, efficiency, legitimacy, and justice. It shows that efficiency is increasingly mediated by technical metrics such as predictive accuracy and system performance. Similarly, legal legitimacy continues to depend on normative justification, even as computational processes influence how decisions are evaluated. In the domain of justice, individualised reasoning coexists with system-level approaches based on statistical patterns, generating new tensions within legal practice. Through a series of case studies, the article demonstrates how these dynamics emerge in concrete legal contexts. It concludes that the impact of artificial intelligence on law is best understood not as a process of substitution, but as a reconfiguration of the epistemic and institutional conditions of legal reasoning.