Summary

The first paragraph of the poem, “The Brain is Wider than the Sky” by Emily Dickinson.

The Brain—is wider than the Sky—
For—put them side by side—
The one the other will contain
With ease—and You—beside—.
It required the reader interpretation, to understand what is the message that the author is trying to communicate. It seems that the author compares them "put them side by side" the brain, which could be understand as knowledge, in comparation with the sky, using an analogy to make this comparation. in the second paragraph that first impression can be backed up with the:
"The Brain is deeper than the sea—
For—hold them—Blue to Blue—
The one the other will absorb—
As Sponges—Buckets—do—".
As sponges absorb nutrients and particles, the human brain absorbs knowledge and information. The author message seems to be clearer after reading the second paragraph about her comparation between human knowledge and the sky. I personally don't agree with this analogy and don't personally like that comparation, humans are ephemerals, meaning that one day we will pass away. The sky is ephemeral as well, but it has existed along with the Earth for billions of years and would exist for another billions of years, civilizations and species had passed away during millions of years, but the sky is still there. The knowledge that a person can collect during their life has a capacity, it is not infinite, for those reasons at that moment I particularly didn't agree with the author message in this poem. by the third paragraph The Brain is just the weight of God—
For—Heft them—Pound for Pound—
And they will differ—if they do—
As Syllable from Sound—.
After reading this paragraph, it changes the perception of this poem, as the author, maybe it could be referring to the human capacities, where some people could agree or not, as human in their capacities had been able to travel in the sky and go beyond it and travel outside of the sky.

In the other hand the poem "The Soul Selects her own society" brings me to a closer agreement with the author, it could be interpreted as how human select and choose a society or societies to be part and feel part of it. I got to that conclusion, especially after reading the second and third verse of the first paragraph "Then — shuts the Door —
To her divine Majority —". Humans are social species that lives in societies, it interpreted, that by a divine majority could mean the feeling a person obtain after being part of a society.