The Brain — is wider than the Sky —
For — put them side by side —
The one the other will contain
With ease — and You — beside —

The Brain is deeper than the sea —
For — hold them — Blue to Blue —
The one the other will absorb —
As Sponges — Buckets — do —

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 —

~by Emily Dickinson, found on https://en.wikisource.org/wiki/The_Brain_%E2%80%94_is_wider_than_the_Sky_%E2%80%94,

The idea that the Brain is wider than the Sky is thrilling, and a paean to the imagination seems altogether fitting for a lover of science fiction and fantasy. But, sometimes to my frustration and sometimes to my joy, the poem is wrong.

It’s not that the imagination isn’t astonishing–it has, one way or another, given us space travel, language, Van Gogh, and relativity. But really, to quote Richard Feynman, “I think nature’s imagination is so much greater than man’s that she’s never going to let us relax.” Even today there is a vast amount about the universe that we cannot conceive, let alone understand or imagine or invent–never-before-seen species, physical laws incomprehensible through anything but poor analogies and abstract mathematics–even the workings of the human body.

I suspect that, on the human level, this is one reason that many mainstream critics prefer the realistic to the fantastic: observation generally yields a  richer texture and sometimes deeper insights than speculation. Just as when I draw from sight, I get more detailed, pleasing, and surprising results than when I draw from my imagination, fantasy and science fiction can dissolve into barren and ill-considered abstraction (utopias, e.g.) or simplistic templates either inherent in our minds or inherited from other literature, and while, well done, they can broaden our horizons or fill us with wonder, they often do not convince the most sophisticated readers to suspend disbelief.

But this doesn’t mean, of course, that science fiction and fantasy are inferior. Sometimes an idea (a happy matriarchal society, say, or a two-dimensional world) is more interesting and I even dare say more important, however sketchy, simplified, and unrealistically developed, than the minutest, most recognizable depiction of, say, a university professor having a kind of bad day (if his–his because I’m pretty sure he’s male and cheating on his wife–bad day turns out to subtly reveal profound truths about the human condition, I will concede that they are equally important. Ha.). Sometimes simplification and idealization is a source of beauty and emotional power in itself (fables and fairy tales, say). And much of the best speculative fiction is great precisely because it combines observation and imagination in new ways–whether the observation is in the area of science, as in hard science fiction, or history, as in epic fantasy, or (like most of mine) in the staple areas of litfic (psychology of smaller-scale interpersonal interactions and inner worlds).

Meanwhile, maybe the poem isn’t as wrong as I think. Maybe we can read “the Brain” as “the collective activity of human Brains with aids like writing and supercomputers” and not “a single human Brain.” Even on this reading, absorbing the Sea is a hugely ambitious goal to set for humanity. Or perhaps she meant that the brain is a kind of thing, the same kind of thing as God is or would be if God existed, that can absorb almost anything, given sufficient memory and imagination and other “braininess”–not that any brain that exists now could actually do this.

A third possible meaning comes to my mind as well. Helen Vendler, the critic whose book of Emily Dickinson poems with commentaries introduced me to this poem, interprets the last stanza of the poem as meaning that the Brain sees ideas and language–Syllable–whereas God, through Nature, utters only “unintelligible sounds” (18). Syllables are, then, superior to sounds, and Vendler sees blasphemy.

If we accept this interpretation, it is also possible that what the Brain sees (color, water with all its emotional and mythological associations) is the enlightened syllable next to the chaotic sound of all the quarks in the water and all the neurons in the giant squid (not to mention the myriad unique perspectives of said squid and the sharks and the pufferfish and the tube worms and the dolphins). But, if so, that is throwing away unthinkable amounts of reality. There is a hilarious shortsightedness in any view that claims that only what we perceive or know or have words for is real or important. That kind of shortsightedness is one thing speculative fiction should work against.