These were two highly influential figures in the history of socialism. But which of these quotes can only be attributed to the figure on the right?

I would say that Karl Marx and Freidrich Engels were the two founders of socialism and communism but I couldn't find the quotes. They developed the theories of dialectical and historical materialism and also wrote the Communist Manifesto.

The quotes that really popular by Rose Luxemburg was Those who do not move, do not notice their chains.

According to her, many people believed to overlooked the problem that displayed within the current society where many people are exploted by others and they're not even realizing it. She believed that If they want to escape their misery, they have to first acknowledge the existing problem.