Nielsen is perhaps most closely associated outside Denmark with his six symphonies, written between 1892 and 1925. The works have much in common: they are all just over 30 minutes long, brass instruments are a key component of the orchestration, and they all exhibit unusual changes in tonality, which heighten the dramatic tension. From its opening bars, Symphony No. 1 (Op. 7, 1890–92), while reflecting the influence of Grieg and Brahms, shows Nielsen's individuality. In Symphony No. 2 (Op. 16, 1901–02), Nielsen embarks on the development of human character. Inspiration came from a painting in an inn depicting the four temperaments (choleric, phlegmatic, melancholic, and sanguine).