I was reading some of Nietsche's works and ran across the ultimate question...
 
What, if some day or night, a demon were to steal after you into your loneliest loneliness and say to you: ‘This life, as you now live it and have lived it, you will have to live once more and innumerable times more; and there will be nothing new in it, but every pain and every joy and every thought and sigh… must return to you—all in the same succession and sequence—even this spider and this moonlight between the trees and even this moment and I myself. The eternal hourglass of existence is turned over again and again—and you with it.' - Freiderick Nietzche, The Gay Science

 
So, the question in each and every thing, do you want this once more and innumerable times more?
 
How well disposed would you have to become to yourself and to life to crave nothing more fervently than this ultimate eternal confirmation and seal?