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.
Marxism
This class struggle that is commonly expressed as the revolt of a society's productive forces against its relations of production, results in a period of short-term crises as the bourgeoisie struggle to manage the intensifying alienation of labor experienced by the proletariat, albeit with varying degrees of class consciousness. This crisis culminates in a proletarian revolution and eventually leads to the establishment of socialism—a socioeconomic system based on social ownership of the means of production, distribution based on one's contribution and production organized directly for use. As the productive forces continued to advance, Marx hypothesized that socialism would ultimately transform into a communist society; a classless, stateless, humane society based on common ownership and the underlying principle: "From each according to his ability, to each according to his needs".