In 1913 Lenin identified three intellectual sources of Marxism: German philosophy, English political economy, and French utopian socialism—each in turn created in the social conditions of their societies. But the process did not end there. Marxism continues to grow and to learn from the most advanced, liberating ideas of each period. (It is also influenced in negative ways, narrowing its horizons and getting dragged along by fashion in times of defeat). Here, I want to identify four contemporary sources of enrichment of Marxism: ecology, feminism, national/racial struggles, and pacifism. It is important to recognize them as sources of ideas, not only as allies in political struggles. Their interaction with Marxism is, of course, different from the pre-Marxist sources. They come to Marxism from the outside, but from an outside already influenced in part by Marxism, and they are both welcomed and resisted.
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