Theory of the productive forces

Empirical support

The most influential philosophical defence of this idea has been promulgated by Gerald Cohen in his book Karl Marx's Theory of History: A Defence. According to this view, technical change can beget social change; in other words, changes in the means (and intensity) of production causes changes in the relations of production, i.e., in people's ideology and culture, their interactions with one another, and their social relationship to the wider world. This view point is a foundation of Orthodox Marxism.
In this view, actual socialism, being based on social ownership and a wide distribution of an abundant surplus product, cannot come to pass until that society's ability to produce wealth is built up enough to satisfy its whole population and to support socialist production methods. Using this theory as a basis for their practical programmes meant that communist theoreticians and leaders in most socialist states, while paying lip service to the primacy of ideological change in individuals to sustain a communist society, actually put productive forces first, and ideological change second.
The theory of the productive forces is encapsulated in the following quote from The German Ideology:
[I]t is only possible to achieve real liberation in the real world [...] by employing real means[.] [S]lavery cannot be abolished without the steam-engine and the mule and spinning-jenny, serfdom cannot be abolished without improved agriculture, and that, in general, people cannot be liberated as long as they are unable to obtain food and drink, housing and clothing in adequate quality and quantity. "Liberation" is a historical and not a mental act, and it is brought about by historical conditions, the development of industry, commerce, agriculture, the conditions of intercourse [Verkehr].
— Karl Marx, The German Ideology, "Part I: Feuerbach. Opposition of the Materialist and Idealist Outlook"