Another thing that Marx did to give his theory an apperance of scienticity is to rely on “utopian socialism”, a school of thought developed by a couple of people I mentioned above (Cabet, Saint-Simon, Fourier) who employed the Enlightenment science and Reason to describe the perfect society. It was a kind of caricature of Condorcet.
This serves as the perfect argument for liberal conservatives for saying that giving a central role to Enlightenment science and Reason will lead to Marxist stalinist dictatorship. Understand: we must stick to religion and traditions.