Lyric discussion by BH4NE5 

'massofclouds' and 'ripelivejam' seem to be on the right track. The narrative isn't as important as the impression made by the repetitive chorus: "We must live in the moment". The song uses a science fiction story as a platform to approach existential problems and universal concerns facing everybody. What can I say, The Flaming Lips love to do that kind of stuff.
This song expands on the theme of mortality from "It's Summertime" and "Do You Realize??". "It's Summertime" tells us to embrace the world around us and asks us to leave the past/inner turmoil behind. "Do You Realize??" confronts the listener with the inevitability of death looming in the future and tells us go with the natural rhythm of the world; to love the people in our lives while we can.
Considering these other songs, "All We Have Is Now" acts as a summation. Without the worries of the past and future, THAT is what we are left with. Perhaps we are supposed to empathize with this character who is told that they can't wait for a future to live out their aspirations. That would make sense. D.Y.R. tells the listener we can't live forever the same way that the 'stranger from the future' confronts himself. I'm not rejecting the other points of view. People are supposed to interject themselves into the music they listen to, however, several of the interpretation listed seem to be sparked by the dejected tone of the song. Ignoring the verses and focusing on the phrase, "We're not going to make it", makes it easy to believe the song is discussing a relationship reaching a dead-end.

Didn't read all the way to the comments left by 'nebulousnearnesses' and 'bt88' until now. Amazing to see them nail the point with such shorter posts. I'm jealous

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