It is most certainly known that our eyes have lenses to focus the light and rods and cones on the retina to actually do the "seeing". Each of these millions of receptors has a responsibility for color. Some of us are color blind, meaning that we don't have enough of a certain mix of rods or cones and there is always a philosophical discussion about "is my 'blue' the same as your blue"? Perhaps the enchantment of stained glass is that our eye can catch our favorite color no matter who we are as there is something there for everyone. Here is Feynman the physicist talking about the wonders of it:
There is an old saying that goes something like "in order to see something, you must look directly at it". Obvious and true. I think of churches with the magnificent stained glass behind the altar (where we are supposed to focus our attention) and the ones along side, to catch the sunlight and bath the interior with color (atmosphere perhaps or reflecting in radiant light?) - remember what Feynman says (above) about light that passes you buy.
So today, just look closely at things and be happy you can see stuff for what it is.
