Why I wear glasses
I wear glasses because if I don’t wear them I get a headache.
The left lens of my glasses does nothing. The main correction in the right lens is prismatic: it only bends the light, it doesn't focus it. Without this correction the images from my two eyes don’t quite coincide, although I am not aware of seeing double. You could perhaps say that I see one-and-a-half.
So you could say I wear glasses to see less.
And that if I don’t wear them I get headaches because I see too much, and it doesn’t all fit in my head.
What a sorry indictment of my head!