Lyric discussion by musicforlife! 

Haha you know when you're learning about Shakespeare in high school and sometimes you have to "put your dirty mind on"?

Well, dear Mr. Gibbard does some wonderfully intelligent wordplay with these lyrics: "your heart is a river that flows from your chest through every organ your brain is the dam and i am the fish who can't reach the core."

Just put your dirty mind on. The fish = semen, the core = his/everyman's 'goal.' He can't get to his goal because 'her mind' keeps saying "No." Gibbard does this all with keeping in the metaphor of the verse.

But the best thing about this is you can interpret it any way you want. It doesn't have to be about sex... it's certainly not sung that way. Although he does a good job of sliding these things in: if you're looking for them. Look at Company Calls Epilogue, or 405 (or even, more bluntly, at We Looked Like Giants). Sometimes you just have to 'put your dirty mind on' with Death Cab.

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