Centrism has a specific meaning within the Marxist movement, referring to a position between revolution and reformism. For instance, the Independent Social Democratic Party of Germany (USPD) and Independent Labour Party (ILP) were both seen as centrist because they oscillated between advocating reaching a socialist economy through reforms and advocating revolution. The parties that belonged to the "so-called" Two-and-a-half and Three-and-a-half Internationals, who could not choose between the reformism of the social democrat Second International and the revolutionary politics of the Communist Third International, were also exemplary of centrism in this sense. They included the Spanish Workers' Party of Marxist Unification (POUM), the ILP and Poale Zion.