The river as a metaphor for „the world“, „the things“, „time“, etc. is ubiquitous in philosophy. This paper starts with a short-story by Bertolt Brecht and investigates the meaning of the metaphor in Brechts story about philosophy and transfers this to Hercalitus‘ and Wittgenstein‘s use of the river-metaphor. The paper differentiates the river-metaphor into two „rivers“, an actual river and a metaphorical river. Brecht‘s story gives an account of philosophy as criticizing the metaphorical river. With Wittgenstein and Marx the paper suggests a critique of language that goes back to the actual river. This critique of language can help to solve problems of modern moral philosophy.