Value-form
The Western Left academics are nowadays very happy to talk about "varieties of capitalism", but talking about "varieties of socialism" remains almost an absolute "no-no". Most Marxists continue to believe in "only one" (Marxian) socialism: either that, or nothing at all. "Either" a society or movement conforms to the true concept of socialism, "or" it does not; and if it does not, it "cannot be" socialism. However, precisely "because" there are many different Marxist beliefs about socialism, Marxists cannot agree among themselves whether Soviet-type societies were socialist, capitalist, or something else. Some countries meet with the moral expectations which Marxists have, and others do not.Originally Marx and Engels themselves had heckled the advocates of "true socialism", but later Friedrich Engels and Karl Kautsky promoted Marxist socialism as the one and true "scientific socialism" within the Socialist International. When he was 43 years old, Lenin stated: "The Marxist doctrine is omnipotent because it is true". Lenin's Communist International (a deliberate split with the social democrats) adopted Marxist socialism as its official political doctrine.
Marxist–Leninist atheism
Marxism is materialism. As such, it is as relentlessly hostile to religion as was the materialism of the eighteenth-century Encyclopaedists or the materialism of Feuerbach. This is beyond doubt. But the dialectical materialism of Marx and Engels goes further than the Encyclopaedists and Feuerbach, for it applies the materialist philosophy to the domain of history, to the domain of the social sciences. We must combat religion — that is the ABC of all materialism, and consequently of Marxism. But Marxism is not a materialism which has stopped at the ABC. Marxism goes further. It says: "We must know how to combat religion, and in order to do so we must explain the source of faith and religion among the masses in a materialist way. The combating of religion cannot be confined to abstract ideological preaching, and it must not be reduced to such preaching. It must be linked up with the concrete practice of the class movement, which aims at eliminating the social roots of religion."