Lyric discussion by Annelise 

I think valrus (who seems to be rather intelligent and insightful) hit the nail on the head with "Sometimes we forget even if we promise not to"... I believe that this idea works, and is probably the only meaning that maintains textual integrity.

It's clearly not an unintended error, so don't let it bother you: you can tell because it's such a central part of the song that, firstly, she would have checked her definitions whilst writing; and secondly, if it were a mistake it would most likely have been picked up in the publishing process. Joanna Newsom is incredibly clever: she pays attention to detail and scrutinises her work laboriously. The simplicity of these two stanzas and the way they stand apart structurally/conceptually is also perfectly inclined towards a deliberate play with ideas: assuming that valrus' suggestion is correct, we have here an example of Joanna taking her concept, and wrapping it up neatly into a couple of lines of condensed metaphor. This is very characteristic of her poetry, and is therefore not surprising enough to be assumed a mistake.

The idea itself also fits really well in its context, and I think is very clever, very deep, and brilliantly penned. The the speaker she is trying to hold onto her memory of her sister's closeness, but it slips away into the mists of memory and the distance caused by Joanna not having access to the depths of her sister's world. This is part of the "sky that is gaping and yawning", and echoes the ideas of loss, distance and desire that's just out of reach, which fill the entire song. This is redeemed by the fact that "the ties that bind, they are barbed and spined and hold [them] close forever", but nonetheless the intensity of the feeling is real.

Anyway, ten gold stars for you Robindra, for picking it up! Not a great deal of the audience would, I assume... I'm pretty impressed :-)

I agree that the switching of the definitions is not an accident, and this is supported in the line,

"Though there is nothing would help me come to grips with a sky that is gaping and yawning".

She of explains there that nothing will help her understand the stars or space like her sister does.

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