Daily Archives: December 15, 2017


Do you see what I see?

Well, how are your eyes?

For that matter, how are mine?

I wear glasses. I need them to see at any distance past book reading. But that’s not the issue. If I take them off, the world may be blurry, but it is still bright and dark in the same measure. I lose only the ability to see the edges clearly. And with my glasses on, I can find my way in the dark, especially if the lights have been off for a time.

You probably know the term a dark-adapted eye. If you have gone out to the countryside at night, away from lights, perhaps to peruse the Perseids or, as last night, enjoy the Geminids (two of the meatier meteor showers), you will find that you can see a Carl-Sagantic quantity of stars, and you can also see more clearly the edges of the trees and fences and hills: earth and heaven, still there and yet nowhere, a silent utopia, a dark paradise. And if someone turns a light on, your eyes will water and you will wince. But to an eye fresh from the lit indoors, the stars are mostly invisible, the trees indistinguishable, the fence a blind hazard, the hills a mere border between black and blacker. Your dark paradise is lost in the afterwash of light; you regain your utopia when you regain your scotopia.

Scotopia. That oto may as well be your two wide eyes around your nose, scoping for photons. The start of it is from Greek σκότος skotos ‘darkness’ (related, way back in Proto-Indo-European, to shadow). You may recognize topia as in utopia, meaning ‘land, place’, but that’s not this; if you see that, you have the edge wrong. This is the opia in myopia and presbyopia (both of which I have), referring to eyes and vision. If you are in the land of darkness, you need dark-sight or you will go only by feeling. You need scotopia.

Light levels are relative, of course. Our eyes are made to handle a certain range, but they do adjust. If you are always surrounded by bright whiteness, you will be confounded by blackness until you have stepped in and away and adjusted your eyes. If something has always seemed too dim or obscure to be approached, a gradual reduction of the light levels may lead you to adjust and find many things you can discern. If the lights go out abruptly, at first you are lost, but at length perhaps you can find your way thanks to scotopia.

Some people are not so able, though. Turn off the lights and everything is flat and uncontrasting. And no matter how able our receptors, we still have our pupils dilated fully, which reduces sharpness and depth of field. A book I can read quite well in good light may prove too much of a challenge for me in dimness. Even if you are well endowed with sensitivity, lack of focus can lead you to lose definition and fail to see boundaries. You need the edges to see the things.

We are now in a time when scotopia is very useful. It is useful at all times, but the light is at its least in this season. Let your eyes adjust. But be aware: there is still much to resolve, and I don’t recommend going only by feeling.