Esperanto is a language introduced in 1887 by Dr. L.L. Zamenhof after years of development. From his youth he had contemplated the idea of creating a simple international language which would facilitate and advance relations and mutual understanding between nations. In 1878, he completed the writing of the first pamphlet which contained the fundamentals of the new language. It contained only 900 root words and a grammar with 16 rules. It was published in 1887 under the title Lingvo Internacia ("International Language"). Zamenhof signed it with the pseudonym "Doktoro Esperanto" ("Dr. Hopeful"), hence the name of the language. At first Zamenhof encountered opposition and mockery, but he succeeded in gaining numerous enthusiastic supporters in every country including renowned thinkers and scientists. Zamenhof published translations from German, English, and Russian literature, as well as from the Bible, in order to prove that Esperanto, in spite of its simplicity, could become a literary language. In 1905, in France, he convened the first international congress of Esperantists. In 1910, when the sixth congress was held in Washington, Zamenhof visited the United States and delivered a series of lectures in Esperanto. Two statues were erected in Zamenhof's honor in Poland—one in Warsaw (1928) and the other in Bialystok (1934), his native town. Zamenhof remained close to Jewish problems. He was one of the first members of Hovevei Zion, and in 1901 published a pamphlet, Der Hilelismus, where he presented Judaism as the philosophy of humanism. He published an Esperanto textbook in Hebrew.