 He was also interested in general linguistics, methodology and language philosophy, and published a well-received introduction to language history, "Johdatus kielihistoriaan" (1946).He was among the few scholars in Finland between 1940 and 1965 who were interested in the international development of theoretical linguistics, and he presented the new ideas, such as the proto-language concept and transformational syntax, to Finnish audience.He took a skeptical stance towards some of the new developments, especially transformational generative grammar.