Offering a current reflection on Raphael Walden's 1977 article, ‘The Subjective Element in the Formation of Customary International Law’, this contribution seeks to illustrate that considerable clarity has been achieved over the decades with regard to several long-standing questions associated with customary international law, not least those surroundingopinio juris. Accumulated practice and constructive scholarship have supplied insights into, and indeed answers to several of the controversies that have bedevilled the theory of this central source of international law. While it may inherently defy exact formulations, and some theoretical questions remain, customary international law is thus today not only as present in the international legal system as it has always been but is also better understood.

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不再是一个谜？与习惯国际法相关的法律意见和其他理论争议

本文提供了对 Raphael Walden 1977 年文章“习惯国际法形成中的主观因素”的当前反思，旨在说明几十年来与习惯国际法相关的几个长期存在的问题已经取得了相当大的清晰度，尤其是周围的人法律确信. 积累的实践和建设性的学术研究为困扰这一国际法核心渊源理论的若干争议提供了见解，并确实为这些争议提供了答案。虽然习惯国际法本身可能无法准确表述，并且仍然存在一些理论问题，但因此，今天的习惯国际法不仅一如既往地存在于国际法律体系中，而且也得到了更好的理解。