In this paper, the author explores the question of whether formalizing the Canadian law of reception would lead to an increase in the domestic influence of international law. He begins by briefly recounting Canada’s decidedly informal law of reception and, through a review of academic commentary, suggests a relationship between informality and international law’s historically weak influence on judicial reasoning. Tying this commentary to seemingly sociological perspectives on globalization, judges’ international legal personality and the changing forms and functions of law, he forwards the hypothesis that judges’ subjective recognition of the authority of international law can be engendered, modified and/or regulated through the procedural use of more familiar domestic legal authority. This hypothesis is then tested through a comparative analysis of the impact which international law has had in South Africa, where an historically informal law of reception akin to Canada’s has been replaced with clear and robust constitutional rules obligating the judiciary to consider and use international law. The author observes that there are no perceptible differences in the two jurisdictions; in neither country does international law exert a significant, regular or predictable impact on judicial reasoning. He concludes, modestly, that there is no available evidence to support the belief that Canadian judicial practice would change if the Canadian law of reception were formalized. He further concludes, less modestly, that this has significant implications for underlying legal theory and, in particular, that theories concerning how the domestic impact of international law can be augmented, though seemingly sociological, are decidedly positivist in orientation. Given that judges’ subjective attitudes towards international law are not perceptibly linked to domestic legal procedures, international, comparative and transnational legal theorists must, either, find evidence to demonstrate this link, or, recognize that their theoretical allegiances are divided between two, inconsistent traditions: legal positivism and the sociology of law.