I found the English title of a
Silva-method-book that is specifically about vision.
What it basically says is that if you can see life "truthfully" ( bluntly put;what is true for you; not closing your eyes/yourself from things you do not want to admit to yourself ) you gain perfect vision.
Is a bit like what Adam16 explained, though, just from a different angle.
Booktitle: "Improve your vision" by Martin Brofman.
p.s ops! might not be Silva... read so much I sometimes get them mixed up. I know I liked the book though.
[This message has been edited by laughing-heart (edited December 20, 2002).]