How did Karl Marx describe the conflict between the bourgeoisie and the proletariat?

For Karl Marx, the conflict between the bourgeoisie and the proletariat is the defining feature of the capitalist era, which he viewed as a continuation of the historical struggle between opposing social classes.12

Marx described this relationship as inherently exploitative. The bourgeoisie, as owners of the means of production, amass wealth by siphoning off the surplus value created by the workers. In this system, the proletariat is reduced to a mere appendage of the machine, losing both independence and the fruits of their labor. This process creates deep alienation, as workers are estranged from their work, their products, and each other.32

Marx argued that this contradiction is unsustainable. He believed the bourgeoisie produces its own "grave-diggers," as the development of industrial capitalism creates the material conditions for the proletariat to eventually overthrow the ruling class. This inevitable revolution would abolish private property and class antagonisms, leading to a society where the free development of each individual becomes the condition for the free development of all.134