He studied harmony and counterpoint with Zaremba and instrumentation and composition with Rubinstein. The Conservatory benefited Tchaikovsky in two ways. It transformed him into a musical professional, with tools to help him thrive as a composer, and the in-depth exposure to European principles and musical forms gave him a sense that his art was not exclusively Russian or Western. This mindset became important in Tchaikovsky's reconciliation of Russian and European influences in his compositional style. He believed and attempted to show that both these aspects were "intertwined and mutually dependent". His efforts became both an inspiration and a starting point for other Russian composers to build their own individual styles. Rubinstein was impressed by Tchaikovsky's musical talent on the whole and cited him as "a composer of genius" in his autobiography. He was less pleased with the more progressive tendencies of some of Tchaikovsky's student work. Nor did he change his opinion as Tchaikovsky's reputation grew. He and Zaremba clashed with Tchaikovsky when he submitted his First Symphony for performance by the Russian Musical Society in Saint Petersburg. Rubinstein and Zaremba refused to consider the work unless substantial changes were made. Tchaikovsky complied but they still refused to perform the symphony. Tchaikovsky, distressed that he had been treated as though he were still their student, withdrew the symphony. It was given its first complete performance, minus the changes Rubinstein and Zaremba had requested, in Moscow in February 1868. Once Tchaikovsky graduated in 1865, Rubinstein's brother Nikolai offered him the post of Professor of Music Theory at the soon-to-open Moscow Conservatory. While the salary for his professorship was only 50 rubles a month, the offer itself boosted Tchaikovsky's morale and he accepted the post eagerly. He was further heartened by news of the first public performance of one of his works, his "Characteristic Dances", conducted by Johann Strauss II at a concert in Pavlovsk Park on 11 September 1865 (Tchaikovsky later included this work, re-titled "Dances of the Hay Maidens", in his opera "The Voyevoda"). From 1867 to 1878, Tchaikovsky combined his professorial duties with music criticism while continuing to compose. This activity exposed him to a range of contemporary music and afforded him the opportunity to travel abroad. In his reviews, he praised Beethoven, considered Brahms overrated and, despite his admiration, took Schumann to task for poor orchestration.