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.
Criticisms of Marxism
The Austrian School argues that this fundamental theory of classical economics is false and prefers the subsequent and modern subjective theory of value put forward by Carl Menger in his book "Principles of Economics". The Austrian School was not alone in criticizing the Marxian and classical belief in the labor theory of value. British economist Alfred Marshall attacked Marx, saying: "It is not true that the spinning of yarn in a factory [...] is the product of the labour of the operatives. It is the product of their labour, together with that of the employer and subordinate managers, and of the capital employed". Marshall points to the capitalist as sacrificing the money he could be using now for investment in business, which ultimately produces work. By this logic, the capitalist contributes to the work and productivity of the factory because he delays his gratification through investment. Through the law of supply and demand, Marshall attacked Marxian theory of value. According to Marshall, price or value is determined not just by supply, but by the demand of the consumer. Labor does contribute to cost, but so do the wants and needs of consumers. The shift from labor being the source of all value to subjective individual evaluations creating all value undermines Marx's economic conclusions and some of his social theories.