Karl Marx believed that knowledge was historically and culturally relative. In every society people believed that their knowledge, their perceptions of the world, values, standards of behavior represented their culture as best in the absolute sense. They failed to see how their culture was in fact shaped by their historical circumstances. For Marx, the culture was decisively shaped by the type of economy and the sort of prevailing relationships to the means of production, by the economic base. The leading ideas in a society are those that the dominant group finds congenial and acceptable in terms of its basic economic interests. The dominant groups, the owners of the means of production are thus not only the rulers of the state; they also are the rulers or arbiters of approved and acceptable ideas and knowledge.
These insights pose dilemma for Karl Marx because if ideas are relative, there being no absolute standard of truth, why should anyone listen to what he has to say. How anyone can criticize with any conviction one ideology in terms of another? According to Karl Marx, the ideas and standards of the bourgeoisie did not fit reality in that they did not enable them to explain the anomalies brought about by the contradictions generated by the capitalist social system. Marx did not believe that the truth could be discovered. For him, scientific work could produce the truth. He believed that as his own work was scientific, then he produced true findings.