After reading Edward Bellamy's "Equality", Pannekoek became a convinced socialist and started studying Karl Marx's theories. Soon Pannekoek became a well-known Marxist writer, writing for both Dutch and German magazines. His astronomical and socialist careers first clashed when he was reprimanded for leading a strike support committee and was treated with dismissal from his job at the observatory by the Dutch government. Around the same time, he was growing dissatisfied with the stale atmosphere and outdated methodologies at the Leiden Observatory. He was offered the option to become a lecturer in Historical materialism at the school funded by the Social Democratic Party of Germany. His radical opinions soon got him in trouble with both the German government and the labor unions.