Lyric discussion by photoperitus 

Cover art for Binary Sea lyrics by Death Cab for Cutie

I love this song - especially the line

"For if there is no document, We cannot build our monument"

which I think is referring to everyone's need to share their every move on social media. People feel like something can't be special or enjoyed unless they have several pictures of it and they share it with their friends on the internet in some way.

"Oh Atlas could not understand The world was so much smaller than The one he used to hold before "

Atlas is a figure in Greek mythology - he's said to be holding the planet (or all of "the heavens", the celestial spheres) on his shoulders. The world has gotten "smaller", as in people have become so confined to their technological devices that they aren't experiencing things fully and really immersing themselves in the joys of life because they're so busy making sure everyone knows what they're doing and how great it is.

"the weight, it brought him to the floor As you watched him struggle to his feet You took photos capturing his defeat And messaged them to all your friends And we all laughed at his expense"

As people become more self-involved and socially inept and lack the ability to communicate face to face and enjoy simple conversation, the world becomes heavier and crumbles, but all anyone is concerned about is getting a good picture of the collapse and sending it to their friends.