The article is a reaction to the existing in the modern literature tendency which exaggerates the religious mind’s positive role in the cultural development and underestimates the role of atheism and free thinking. The author considers religion and atheism as a unity of the opposites, as two essential aspects of culture. The article traces the history of European atheism – from prehistoric times up to nowadays, and demonstrates that it played an important role in the development of science and modern social institutions. The polemics between these two types of world outlook is an everlasting and unalienable factor of culture’s development.