For a fleeting moment of eternity at the end of his life, Richard Wagner experienced the deep happiness he had been seeking throughout his life. The last words he wrote in his treatise On the Feminine in Human Nature, on February 13, 1881, were ''love - tragedy''. Although it is usually far too simplistic to interpret works of art purely in the context of biological information, several of Wagner's compositions really do have a dairy-like nature, with the character of personal revelations. One such work is the Siegfried Idyll, a symphonic overture from 1870 that Wagner wrote for his wife Cosima to remember the birth of their eldest son. Another is the song cycle Wesendonck Lieder, which Wagner wrote in stages over 1857 and 1858. Less well-known are the sonate fur das Album von Frau M.W. from 1853 and a ''musical letter'' to Mathilde, entitled Sleepless.