Victor Frankl offers this thought experiment:

“Imagine that you are sitting in a concert hall and listening to your favorite symphony, and your favorite bars of the symphony resound in your ears, and you are so moved by the music that it sends shivers down your spine; and now imagine that it would be possible (something that is psychologically so impossible) for someone to ask you in this moment whether your life has meaning. I believe you would agree with me if I declared that in this case you would only be able to give one answer, and it would go something like: ‘It would have been worth it to have lived for this moment alone!’”

Thanks to Maria Popova for this gem –