Most social scientists agree on the the crucial role of the ideological factor in Soviet history.
It does not mean however that the phenomenon of Soviet ideology has been investigated and understood, by either western or Soviet sociologists. An ideology may be evaluated in either positive or negative terms. In positive terms an ideology may be conceived as the expression of the world view of a class. Until recently, most discussions of ideology in the Soviet Union concentrated on the role of Marxist-Leninism, which was considered in many ways as the only true ideology. It was a matter of fact that its role was assumed to be positive and constructive.