The philosophical ideas of Karl Marx fundamentally challenged existing societal norms by critiquing capitalism and advocating for a classless society. His analysis of class struggle and the exploitation of the working class in works like "The Communist Manifesto" and "Das Kapital" highlighted the fundamental inequalities within capitalist systems. Marx’s theories on historical materialism proposed that economic forces shaped societal structures, inspiring revolutionary movements globally. His radical vision for social change influenced political ideologies, labor movements, and critiques of economic systems, presenting a compelling alternative to prevailing capitalist frameworks, making his thoughts integral to modern social theory.