The Communist Manifesto
Having realized that a Communist Manifesto was the basis of a Communist Movement, Karl Marx decided to write a Communist Manifesto.
To write the Communist Manifesto Karl marx did not use his own analysis of Capitalism.
He took the criticism of the bourgeois society of his time by Victor Considerant and made it the first part of the Communist Manifesto.
He took the definition of Communism by Proudhon and made it his own.
He tried to make himself believe that class struggle was the first step from a Capitalist society where man is inhuman to man to a Communist society where man in human to man.