John Lennon's Imagine. Imagine everything is meaningless, and people only live for the moment. Plus, nothing to kill or die for? That means there's no freedom and no love. And this is supposed to be a Hope For A Better World song.
The Fridge Logic of that song is that what he's describing is his own personal BoringHeaven, while mentioning the idea of heaven as one of the evil influences on life. Of course, he's talking about people striving towards a heaven after life, as opposed to trying to create heaven-as-a-place-on-earth (oooh, baby, do ya know what that's worth? sorry...)