Isaac Ignaz Moscheles (; 23 May 179410 March 1870) was a Bohemian piano virtuoso and composer. He was based initially in London and later at Leipzig, where he joined his friend and sometime pupil Felix Mendelssohn as professor of piano at the Conservatory. Life Early life and career Moscheles was born 1794 in Prague, Bohemia, the son of Klara Popper (Lieben) and Joachim Moises Moscheles. He was from an affluent German-speaking Jewish merchant family. His first name was originally Isaac. His father played the guitar and was keen for one of his children to become a musician. Initially his hopes fixed on Ignaz's sister, but when she demurred, her piano lessons were transferred to her brother. Ignaz developed an early passion for the (then revolutionary) piano music of Beethoven, which the Mozartean Bedřich Diviš Weber, his teacher at the Prague Conservatory, attempted to curb, urging him to focus on Bach, Mozart and Muzio Clementi. After his father's early death, Moscheles settled in Vienna in 1808. His abilities were such that he was able to study in the city under Albrechtsberger for counterpoint and theory and Salieri for composition. At this time he changed his first name from "Isaac" to "Ignaz". He was one of the leading virtuosi resident in Vienna during the 1814–1815 Congress of Vienna, and it was at this time that he wrote his enormously popular virtuosic Alexander Variations, Op. 32 for piano and orchestra, which he later played throughout Europe. Here, too, he became a close friend of Giacomo Meyerbeer, at that time still a piano virtuoso, not yet a composer; their extemporized piano-duets were highly acclaimed. Moscheles was also familiar with Hummel and Kalkbrenner. Among the virtuosi of the 1820s, Hummel, Kalkbrenner, Cramer, Herz and Weber were his most famous rivals. While in Vienna, Moscheles was able to meet his idol Beethoven, who was so impressed with the young man's abilities that he entrusted him with the preparation of the piano score of his opera Fidelio, commissioned by his publisher Artaria. At the end of his manuscript, before presenting it to Beethoven, Moscheles wrote the words Fine mit gottes Hülfe ("Finished with God's help"). Beethoven approved Moscheles's version, but appended the words O Mensch, hilf dir selber ("O Man, help thyself!"). Moscheles's good relations with Beethoven were to prove important to both at the end of Beethoven's life. Faith and family Moscheles was still a practising