The Nature of Reasonableness
Stanford Journal of International Law (forthcoming 2025)
46 Pages Posted: 15 Apr 2025 Last revised: 19 Mar 2025
Date Written: March 19, 2025
Abstract
“Reasonableness” sets countless legal standards in America. It also informs standards within foreign jurisdictions, from Lithuanian contract law to Dutch tort law. Legal theorists often assume that reasonableness is vague and variegated, a flexible term with no essential conceptual core across languages, cultures, and jurisdictions.
This Article questions this conventional wisdom. It develops a new alternative theory: Reasonableness has a shared conceptual core, in the U.S. and at least some other languages and cultures. A unique cross-cultural survey-experiment (N = 2,356) examines reasonableness evaluations across Brazil, Colombia, Germany, India, Italy, Lithuania, Netherlands, Poland, Spain and the U.S., finding a subtle commonality across diverse languages, cultures, legal systems, and levels of legal expertise. This discovery has practical implications for judge and jury decision-making in these countries. More broadly, the study represents a legal theory proof of concept: Analysis of specific legal concepts like reasonableness across cultures provides a relief on which the features of one jurisdiction’s concept more clearly manifest. Counterintuitively, local questions of particular jurisprudence can be clarified through more general, multi-cultural and multi-linguistic empirical study.
Keywords: reasonable, reasonableness, legal theory, experimental jurisprudence, comparative law, jurisprudence, legal theory, legal philosophy
Suggested Citation: Suggested Citation