150 years ago, Marx's Capital, was published for the first time. Five decades later the Russian proletariat takes power. Capital represented a scientific revolution. The triumph of the Bolsheviks the first great socialist revolution. How important are these two facts for humanity, for science, for the dream of a radically different world? To 150 years of Marx's Capital and 100 years of the Bolshevik Revolution, it is necessary to read these achievements in the key of synthesis, the most significant aspect of the dialectic.