To really understand and appraise the far-reaching changes which have taken place in science during Soviet times, it is most important to look back on the past and compare it with the present, at this time when our country and with it the entire progressive world are marking the 30th anniversary of the Great October Socialist Revolution. In the three decades since the October days of the Soviet Revo lution in 1917, profound social and economic changes have taken place, historical events have unfurled on the territory of the former Russian empire that have changed the life of the state fundamentally. The history of mankind has never witnessed such a revolutionary trans formation in the development of society as that of old Russia into a socialist state, into a close family of fraternal peoples. In the Soviet Union, the far-seeing conclusions and prognoses concerning the development of society contained in the teachings of Marx, Engels, Lenin and Stalin, began to receive fulfilment. For the first time in the history of mankind a scientific idea ? the scientific theory of Marxism-Leninism ? was consciously made the pivot of the development of a vast state. For the first time a multi-millioned people became active, conscious participants in a great social, scientifically founded process. At the same time science in all its aspects could not but be drawn into this mighty, universal trend of history. It has been decisively transformed during these thirty years ? and not only in scope, quality and specific content. Preserving all the best traditions of pre revolutionary Russian science, it has also acquired features intrinsic to Soviet science, and Soviet science alone. In capitalist society science is employed in the interests of the ruling minority, for the furtherance of antipopular aims. Reactionary forces seek to turn science against humanity, to make it an instrument of plunderous wars, rapacious annexations and the enslavement of nations. In the U.S.S.R. ? the land of triumphant socialism ? science is placed at the service of the people, who are successfully building the new society. The cardinal feature of Soviet Science makes it a genuine people's science. During the years of Soviet rule, our science has made unprece dented progress. This is the truly progressive science, which, as J. Stalin said, "does not fence itself off from the people and does not hold aloof from them, but which is prepared to serve the people and to transmit