Everything ends eventually. Me, you, stars, galaxies, governments, everything.
On its face, this could be an incredibly dispiriting concept, a resignation to fatalism and predestination. Yet I pass graveyards, and I smile, because I know that someday I'm going to die, and time is short.
This is the ultimate permission slip. Do what you will, be an agent for change, attempt to serve a cause higher than yourself. If you succeed, you'll go eventually. If you fail, you'll go too. No harm in trying.
The question is: what will you leave in your wake, what effect, temporary though it may be, will you have on the world?
This isn't chicken soup for your soul. This is a demand. Quit fucking around, and do something worthwhile. Do it now.
When you pass graveyards, smile, and thank them for reminding you exactly why you're here. Thank them for reminding you that time is short, and everything ends.
Thank them for the permission to change the world.