Finnish philosopher Eino Kaila wrote a classic statement of logical empiricism. Having experienced the foundational debates of the Vienna Circle in 1929, Kaila was a keen follower of the further developments of the Circle. His synoptic presentation and analysis of the basic themes, or theses,” of the movement was based on his lectures as professor of theoretical philosophy at the University of Helsinki. The work appeared as a book in Finnish in 1939 and a Swedish translation by Georg Henrik von Wright followed immediately. Earlier, a translation of his philosophical essays from the original German, entitled Reality and Experience, appeared in 1979. However, this is the first translation of Kaila's major epistemological work, which remains a source for re-evaluations of Logical Empiricism.