Marx Brothers stage during the middle of a Groucho monologue to see if Groucho would be thrown off. However, to the audience's delight, Groucho merely reacted by commenting, "First time I ever saw a taxi hail a passenger". When Harpo chased the girl back in the other direction, Groucho calmly checked his watch and ad-libbed, "The 9:20's right on time. You can set your watch by the Lehigh Valley." The brothers' vaudeville act had made them stars on Broadway under Chico's management and with Groucho's creative direction—first with the musical revue "I'll Say She Is" (1924–1925) and then with two musical comedies:
Karl Marx and the Close of His System their "positivist narrowness". The Marxist economist Paul Sweezy rejects Bawerk's view that the theory of value must be abandoned. However, he considers "Karl Marx and the Close of His System" to be the best statement of the argument that the fact that the law of value is not directly controlling in capitalist production requires the rejection of the theory of value. Karl Marx and the Close of His System Karl Marx and the Close of His System () is a critique of Karl Marx's economic theories by the Austrian economist Eugen Böhm von Bawerk, published in English translation in 1898.