The recognition of Marxist-Leninist philosophy and Pavlovian science as the two pillars of Soviet psychology was only accomplished at the end of a long period of discussion. All the major works of the "Classics' predate the Revolution and the ideas of Pavlov and Bexterev were widely known, both in Russia and abroad, long before 1917. However, it was not until after 1930 that the full significance of dialectical materialism was recognized, and the call for the "reconstruction" of psychology on the basis of Pavlovianism was not raised until 1950.