Marx, who was wrong about many (most?) things, only used the expression "dictatorship of the proletariet" about two times, in his twenty-odd books written over a thirty five year period.

Adam Smith, the father of capitalism and author of "Wealth of Nations," only used the term "invisible hand" once in his 1,000 page masterpiece. Contrary to perception, Smith advocated the use of government to regulate the markets, enforce contracts, protect copyrights and patents, curb landlord abuses (whom he thought were "stupid" because they didn't do anything to earn their money). Smith wanted the state to engage in FDR-style public works programs, and wanted public education for (almost) everyone (surprise!).

Alfred Marshall's 'marginalist utility' theory demolished Marxism's surplus value theory of labor, even though throughout most of the 20th century a third of humanity seemed not to notice.