The impact Ferdinand de Saussure’s Cours de linguistique générale (1916) had on Dutch linguistics in the 1930s and 1940s has not yet become the object of a thorough investigation. It can be pointed out, however, that in the interwar period Dutch reactions to the Cours were of a mixed character. When one finds Saussure’s book referred to by leading Dutch linguists such as Etsko Kruisinga (1875–1944), H. J. Pos (1898–1955) and A. W. de Groot (1892–1963), the question should be asked to what extent the Cours was seen as a new and important specimen of linguistic theorizing. Moreover, it can be argued that several Dutch linguists felt themselves to be in a different linguistic tradition. Such is definitely the case with Jac. van Ginneken (1877–1945). He took part in the organization of the first international congress of linguists (1928) and the first international phonetic congress (1932). Although critical of the Cours, he sympathized with the Prague approach to phonology, of which he was one of the early propagandists in Western Europe. However, he did not become a confirmed structuralist. Practising a holistic approach to language and culture he felt more affinity with the ‘Neolinguists’, and tended to revert to 19th-century thinkers such as Wilhelm von Humboldt (1767–1835), as some of his papers clearly show. In an intriguing posthumous essay, Het mysterie der menschelijke taal (‘The mystery of human language’, 1946), Van Ginneken acknowledged that over the years language had become a mystery to him.