An investigation of the role of language in the proces of cognizing, in epistemology. The first chapter is an overview of the philosophical approaches to this problem in more recent periods (Herder till Von Humboldt, Neokantians, conventionalist, neopositivism); in the second chapter the ethnolinguistik approach to the problem incorporated in the Sapir-Whorf hypothesis is elaborated; the third chapter is a more direct attempt to handle the problem, including sections on language and thought, the relation of language/thought and reality, and the influence of language/thought on human behavior.