The Unknown Unknowns

March 7 2019

How to explain colour to a blind man

who was born into blackness.

To a world confined

to sound and smell

the length of an out-stretched arm.

To a singular sense of self,

the space his body occupies

when everything else

is surface.

To bruised shins, booby-trapped rooms,

the feel of skin

the schmeck of food.

To a beautiful face, in the mind's eye,

the brush of her lips

a sunset sky.

Or should I say absence, instead of blackness.

Because black is still a colour,

and if not a colour, then the lack of light

which means you must, at least, have seen light

to understand it.

Like a fish knows nothing of water,

until ripped from its place

into the thin air and dazzling sun

of the alien planet above.

Like an expanding universe

from constant earth,

where solid ground

is the same today

as it will be tomorrow

and we age too slowly to notice.

Physicists have no problem with this,

who say it's not that the universe is ballooning

into unoccupied space

but rather that space itself

is getting larger;

the distance separating things

the time it takes.

There is no intuition

by which one could make sense of this.

It is red

to a man who has no notion of light.

No concept of shadow and depth, colour and shade,

of black and white

degrees of grey.

Yet who moves about in space

navigating obstacles, comprehending shape.

Who reads by touch

and hears in 3 dimensions,

can smell fear's rancid funk.

I can only surmise

that I, also, am blind,

to inaccessible spectra

and wavelengths I don't even know I don't.

What a fine exercise in humility,

admitting my ignorance

the limits of the senses

how much is unknowable.

How I am blinded by the light

hallucinate in darkness.

How I see, but do not look

hear, but fail to listen.

Touch, but do not feel,

eat too greedily to savour.

And take in shallow breaths

heedless of smell.

In a press conference, former US Secretary of Defence Donald Rumsfeld famously said this: because as we know, there are known knowns; there are things we know we know. ... But there are also unknown unknowns—the ones we don't know we don't know. He was ridiculed as a master of disinformation, misdirection, and obfuscation; and in the context of the Bush Administration's rationalizing the invasion of Iraq, this was a legitimate characterization.

But, of course, what he says is perfectly true, and actually a philosophically insightful observation into the nature of reality and the epistemological method. To admit that there are things “we don't know we don't know” takes a certain intellectual humility. This is the same discipline of mind that acknowledges that seeing isn't always believing, and that our understanding of reality is not only highly subjective, but also very possibly incomplete.

A very useful analogy to all this is the one in the poem: that just as a congenitally blind person cannot comprehend colour, there are probably things in the universe our minds are utterly unequipped to even conceive. Trying to imagine a blind person contending with colour is a useful exercise in the theory of mind. The theory of mind, at its most rudimentary, is the understanding that others perceive things differently than we do; and in a more sophisticated sense, is the attempt to understand and even inhabit another's subjective experience. So try imagining what the absence of vision is like. Or for a more demanding task, try imagining a blind person's struggle to conceive of colour. Or for an even more challenging task, try imagining your own struggle to convey to him the sensation of red. When there is no basis for understanding, no common language or shared experience, we are both left utterly in the dark: our realities unknowable, our minds impregnable, our interior lives a black box.