When listening to classical music, one must consider the motives, aims and details a composer would have considered when constructing the very melodies and accompaniments we still hear to this day. Take for example Verklärte Nacht, a one movement piece dedicated for string sextet composed by Arnold Schoenberg. Schoenberg, the Austrian-born composer who founded the Second Viennese School, was a master of atonality and pioneer of the expressionist movement of 20th-century music. His compositions consisted of the 12-tone row, a static, ordered selection of 12 chromatic notes within an octave accompanied by admissible permutations that derive the harmonic and melodic content of a serial work of music. The significance lies in the number of tones, as Schoenberg was believed to be inflicted with triskaidekaphobia, the irrational fear of and aversion to the number 13. Thus, various opuses of Schoenberg, most famously Moses und Aron, had to abide by his inexplicable phobia of the number 13 – the original title of this work was Moses und Aaron, which consisted of 13 letters. Again, the last of Schoenberg's creations, entitled Das Buch der hängenden Gärten, substituted the 13th poem of his 15-part song cycle for a poem labelled ‘12a’, altering the systematic numeric structure to incorporate his fear of the ‘unlucky number 13’. Therefore, was Schoenberg's nonsensical fear of the number 13 in fact responsible for the development of the 12-tone row and, thus, was a psychiatric anxiety disorder the root of musical expressionism? We will never know.