In this brilliant study (his best-known and most controversial), he opposes the Marxist concept of dialectical materialism and its view that change takes place through "the struggle of opposites." Instead, he relates the rise of a capitalist economy to the Puritan determination to work out anxiety over salvation or damnation by performing good deeds — an effort that ultimately discouraged belief in predestination and encouraged capitalism. Weber's classic study has long been required reading in college and advanced high school social studies classrooms.