Jörg Paul Müller, ‘Lehren von Vorrang und Autonomie des Vertragstextes’ in Jörg Paul Müller, Vertrauensschutz im Völkerrecht (Köln and Berlin: Carl Heymanns Verlag KG, 1971) pp. 136-143 [Doctrines of precedence and autonomy in international law].
Jörg Paul Müller is an eminent constitutional and international law scholar and Emeritus Professor at the University of Bern. He dedicated most of his work to the development of fundamental and human rights protection under the Swiss Constitution and the European Charter on Human Rights. He took a particular interest in the relationship of democracy and the rule of law, and developed in parallel to Jürgen Habermass a theory of deliberate democracy. In international law, his main interest was the exploration of the principle of good faith and the protection of legitimate expectations, the subject of his habilitation thesis published in 1971. He subsequently authored together with Luzius Wildhaber the leading Swiss case book on international law Praxis des Völkerrechts (3rd ed. Stämpfli, 2001). The chapter is from his habilitation Vertrauensschutz im Völkerrecht and focuses on the interpretation of the wording of treaties in the light of good faith. Later, he developed a strong interest in the relationship of law and psychology. Much of it was anticipated in his habilitation thesis, showing the need to go beyond legal positivism.
In the chapter on the doctrines of priority and autonomy in the wording of treaties, Jörg Paul Müller introduces Emer De Vattel’s maxim “plain meaning rule”. The rule states that the wording of a treaty which appears to be clear and unambiguous, according to the ordinary linguistic usage, is excluded from recourse with any further technique of interpretation for the will of the parties. This maxim was confirmed in various decisions and findings of international courts. However, the International Court of Justice changed its practice later on towards a less restrictive wording, leaving room to allow other methods of interpretation. The chapter then turns to the points of criticism and summarises where the plain meaning rule has been questioned or even rejected. Müller explicitly mentions the critique the maxim has received from the newer Anglo-American doctrine of public international law, where explicitly wording-oriented interpretation is seen contrary to the identification of valuable expectations that result from the parties wording.
You can find a scan (PDF) of the original text here: Müller Vertrauensschutz im VR_Plain Meaning Rule