The monograph concerns the concept of interpretation of law developed by the Austrian legal philosopher and Neo-Kantian Hans Kelsen (1881-1973). The monograph focuses on the analysis and commentary of the basic assumptions of his concept of interpretation of law presented in the historical and philosophical context.

The monograph discusses the life and work of Kelsen and attempts to reconstruct his concept of interpretation of the law, as well as his views on the subject of interpretation. The study also touches upon the scope of interpretative activities and attempts to answer the fundamental question of whether there are legal texts in which the principle clara non sunt interpretanda applies. Finally, the monograph undertakes a critique of the concept of a "gap in the law". A translation of Kelsen's 1934 article Zur Theorie der Interpretation is included as an appendix to the book.

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