If you can't rely on Mozart, who can you rely on?
Managed to get myself all blue and depressed yesterday (Depression "is an art, like everything else. / I do it very well / I do it so it feels like hell / I do it so it feels real / I guess you could say I've a call"), so decided the only thing to do was turn off all the lights and listen to Mozart's Exultate, Jubilate (K.165). By the time I got to that last towering Alleluia I could feel myself soaring again, I was so prodigiously, dizzily happy.
Thank God for Mozart.
Or rather, Thank Mozart for God.
P.S. So now the only thing that cheers me up when I'm blue is the sound of a castrato singing. Great, just great.