The dispute between Legal Positivists (eg, Hart) and Natural Lawyers (e.g., Finnis) concerns the existence or otherwise of a necessary (conceptual) connection between law and morality. Legal Positivists such as Hart deny this connection and assert the merely contingent relationship of law and morals. However, it can be demonstrated that implicit in the valid sociological method of concept formation of post‐Austinian Positivists are interpretative or ideal‐typical models of the practical rationality of the legal enterprise which are not, and cannot possibly (...) be, value‐neutral. With particular attention to the work of John Finnis and his incorporation of Weberian and Aristotelian methodological principles, this paper exposes, if not the truth of Natural Law Theory, the impossibility of Legal Positivism. (shrink)