Eduard Bernstein (1850–1932) believed that Marx’s theory of social change was generally correct in outline but false or mistaken in several important details. He therefore favored revising Marx’s theory to make it consistent with newly emerging facts—including the fact that the predicted “immiseration of the proletariat” had not occurred. Rather than becoming worse off, Bernstein noted, European and North American workers were increasingly prosperous. This had happened, he claimed, because the capitalist system was “evolving” into socialism as it was transformed by trade unions and by working-class or socialist political parties. Bernstein’s book Evolutionary Socialism (originally published in 1899) provided the classic statement of “revisionist” Marxism.