I have found myself feeling too foolishly happy of late, so I decided to read Schopenhauer's "On the Vanity and Suffering of Life" (The World as Will and Representation, Book II, Chapter XLVI) last night while listening to the soundtrack of life, Lustmord's Heresy. I think Schopenhauer went to even truer depths in the Parerga (see "On the Suffering of the World" in R. J. Hollingdale's selection), but I still got the corrective I needed. For the uninitiated, I would say the chapter is best summed up—Schopenhauer's own eloquence notwithstanding—by a passage he quotes from Shakespeare's King Henry IV:
O heaven! that one might read the book of fate
And see the revolution of the times
. . . how chances mock,
And changes fill the cup of alteration
With divers liquors! O, if this were seen,
The happiest youth,—viewing his progress through
What perils past, what crosses to ensue,—
Would shut the book and sit him down and die.
Truth. It's fantastic.