Harpo Marx York accent his entire life. According to those who personally knew him, Harpo's voice was much deeper than Groucho's, but it also sounded very similar to Chico's. His son, Bill, recalled that in private Harpo had a very deep and mature soft-spoken voice, but that he was "not verbose" like the other Marx brothers; Harpo preferred listening and learning from others. Harpo's final public appearance came on January 19, 1963 with singer/comedian Allan Sherman. Sherman burst into tears when Harpo announced his retirement from the entertainment business. Comedian Steve Allen, who was in the audience, remembered that Harpo spoke for
Influences on Karl Marx social Darwinism. Nonetheless, it is evident that Marx had a strong liking for Darwin's theory and a clear influence on his thought. Furthermore, when the second German edition of "Das Capital", was published (two years after the publication of Darwin's "Descent of Man, and Selection in Relation to Sex"), Marx sent Darwin a copy of his book with the following words: Darwin wrote back to Marx in October, thanking him for having sent his work and saying "I believe that we both earnestly desire the extension of knowledge". According to scholar Paul Heyer, "Marx believed that Darwin provided a materialistic