Thomas Aquinas and the Metaphysics of Law

Abstract

Despite modernity's longstanding aversion to metaphysics, legal scholars are increasingly questioning whether law can be understood in isolation from wider questions about the nature of reality. This paper examines perhaps the most famous of metaphysical legal texts - Thomas Aquinas' still-widely-read Treatise on Law - with a view toward tracing the influence of Thomas' metaphysical presuppositions. This article shows that Thomas' account of human law cannot be fully understood apart from his metaphysics. Attention to Thomas' hierarchical view of reality exposes tensions between Thomas' "top-down" account of law and his sophisticated "bottom-up" observations. For example, Thomas grounds human law's authority in its foundation in the "higher" natural and eternal laws. On the other hand, he is well aware that many if not most legal questions involve "determination of particulars" - the resolution of questions that might reasonably be answered in more than one way. Thomas' metaphysics sometimes works against his inclination to give place to human freedom in the creation of law. Thomas' metaphysical approach also raises important questions for contemporary legal theory. His insistence on addressing the question of law's ontological status, for example, challenges the reductionism of much contemporary jurisprudence and provides a vocabulary for accounting for the wide variety of analytical approaches legal philosophers employ.