[T]he middle class . . . sink gradually into the proletariat, partly because their diminutive capital does not suffice for the scale on which modern industry is carried on, and is swamped in the competition with the large capitalists[.]
Under capitalism, the class system has changed, causing those at the lower level of the middle class to fall into the working class. As explained by the authors, this transformation arises because the middle class, while possessing some capital, does not have the means to compete with the wealthy bourgeoisie. Members of the middle class, unable to continue with their own businesses and workshops, are forced to take jobs and become wage laborers. In this manner, the middle class ceases to exist. The authors contend that this change in social structure will contribute to class revolution because all members of society belong to either the proletariat or the bourgeois class.
[W]hen the class struggle nears the decisive hour . . . a small section of the ruling class cuts itself adrift, and joins the revolutionary class, the class that holds the future in its hands.
While the working men and women of the proletariat class reside at the bottom of the societal structure, the authors believe they hold power in their numbers and can end their oppression by rising up as one. Once this happens, the proletariat will form the decisive block in society, capable of overthrowing the unfair class and economic structure. Some members of the bourgeoisie, recognizing their impending fall, will seek to leave their class to join the proletariat. The authors include that the fact that these bourgeoisie will only join the proletariat as the revolution draws close reveals that they act out of self-interest, not from any sense of morality.
What the bourgeoisie therefore produced, above all, are its own grave-diggers. Its fall and the victory of the proletariat are equally inevitable.
Here, the authors argue that the class system developed by the rise of the bourgeoisie will eventually lead to their own downfall. The proletariat class has become both large and united as its members are forced to work side by side in the factories and industries of the bourgeoisie capitalists. This mingling of the proletarians gives them both the opportunity to communicate and strength, which will be harnessed to overturn their oppressors. In creating a large, new class, the bourgeoisie has unintentionally created a common foe.
WORKING MEN OF ALL COUNTRIES, UNITE!
Marx and Engels conclude The Communist Manifesto with this call to rise up against the bourgeoisie. With just a few simple words, they ask working people all over the world to collectively demand their rights to be able to take an active part in the economic, political, and social spheres. In couching their declaration in such terms, they make a clear statement that they see the coming revolution essentially as a class conflict. The proletarians comprise a majority of the populations in all nations, and if they act together, they can upend the structures that organize society and transform their own lives.