In the Soviet political system, "ideology" in the broadest sense refers to the body of philosophical principles considered axiomatic in Marxism-Leninism. These principles (atheism, a theory of classes and class struggle, and the historical mission of the proletariat) are not subject to change and comprise the fundamental dogma of the ideology. 1 Although they form a common frame of reference and worldview for Soviet leaders, the principles of Marxism-Leninism are not generally evident in policy decisions that are focused on practical matters.