[oakenshield]

Which book did you get? Curious to find out what's in it.

> ... so disadvantageous in an evolutionary sense? Environmental factors (such as staring at a computer screen...)

Well if you're arguing that it's a nurture thing, there are plenty of us who had bad vision at childhood, right from before the dawn of the computer age. You could say that it was not computer screens but books that caused it, but how far back can you make this argument? Any sources for this claim?

[zwegner]

Well, I did too--I started wearing glasses at around age 4. Books and TV would certainly contribute as well--as I understand it, "nearpoint stress" is the main cause of myopia. The eyes are tuned for scanning the horizon for faraway threats; we're naturally more far-sighted. Focusing your eyes closely causes strain, where your eye muscles must contract the lens constantly. Your eyes accomodate this stress by keeping the lens in a contracted position, and by lengthening the eye.

[zwegner]

Oops--I forgot the book. It was this: http://www.amazon.com/Improve-Vision-Without-Glasses-Contact...

(though mine has a more modern looking cover, I guess I have a newer edition?)