Lyric discussion by USCMM 

I have to agree with you wilemi on the part that this is a memory due to the fact that Wilson states "that day."

But, I see that the lyrics in the 3rd part of the song (along with the music) are meant to convey a sense of distance and loss...maybe due to the last time the protagonist saw someone significant (a lover or a parent, etc.). Also to note, the song never specifies a gender for the main character or the hatted person. I feel like this was done on purpose (also in 1st person) so that we would insert our own life into the plot line. Thus, it is Wilson's interpretation of growing up in the 21st century.

I always took "There's black across the sun" to mean a black silhouette surrounded by sunlight. Something similar to this: worldofstock.com/slides/PRE5651.jpg

Also, the term "black" could be equated to as something bad, a scar in the main character's life.

So, all in all, I feel like it is a memory of the protagonist being depressed on the shore line. He see's someone significant in his life who is either talking at him or to someone else...but the sounds of the waves keep him from hearing this person. The person then turns and leaves.

Since it is a memory, the protagonist equates this moment as an example of the distance he feels between him and humanity...that all he hears is "the waves" and crap from those around him and that he feels no real connection with anyone. Everyone just seems distant and unrecognizable. So, it just furthers his depression.

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