<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by JS:
I don't like sitting in a coffin or a box when I'm at home, either, so I don't get your point about natural light at 35,000 feet vs. on the ground.</font>
Lightat sea-level is very different from light at 35K feet (in terms of its content). I cannot understand the fetish for "natural light" when at 35K the light you get through the window is not what your body is used to (natural light under normal conditions). Why is artificial light not good enough?
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Secondly, I would like an explanation as to why one passenger who wants someone else's window shade to be closed is not being selfish, whereas the passenger next to the window shade who would like it open is being selfish.</font>
As AAFA put in, a single shade disturbs the ambience of the whole cabin and disturbs everyone. Just covering or closing eyes will not help people to sleep when there is light coming in from the shades. People who are unable to sleep become irritable amd unable to work at destination ..(fill in the blanks); the whole flight experience is spoilt.
There are a lot of places where we do without natural light. I guess you have never been inside a movie theater or have been lucky enough to have a corner office all through out the life, and hence absolutely need natural light when you are flying.
In summary: people who need light can use the artificial light source, if you need natural light, go the galley or whatever where you can open a shade and take a peek without disturbing the entire cabin. But there is no way you can justify disturbing every one else as "them being selfish"; you have a viable alternative source of light, the people catching up with the Zs do not.
BTW, the comments above are for flights more than a couple of hours or red-eyes.