ABSTRACT
When speaking of 'purposive interpretation' or 'teleological construction', what one usually has in mind are constitutions, statutes, contracts, wills or international treaties – in short, written legal instruments. In the interpretation of treaties, as well as in the general theory of interpretation with respect to written law, notions of a purposive or teleological method have long occupied a dominant position. In the context of the inquiry undertaken, which attempts to draw lessons from the concept of purposive interpretation in the context of treaties that are relevant to the parallel process in the field of unwritten international law, this method of 'typical interpretation of treaties', as it has just been described, is of great importance. The harmonisation of a plurality of purposes of a treaty has become an increasingly acute topic in the law of international investment protection. Domestic courts in several subject areas have long used a method that could be described as typical interpretation of international treaties.
