Depth of field is biologically relevant. I can see more, better, when an area is well lit. http://en.wikipedia.org/wiki/Depth_of_field http://en.wikipedia.org

Depth of field is biologically relevant. I can see more, better, when an area is well lit. http://en.wikipedia.org/wiki/Depth_of_field http://en.wikipedia.org/wiki/Depth_of_field Also your visual cells don't do color below a certain flux level, so brighter "world" means not just are the colors physically brighter, but your eyes can perceive colors "better". Finally brightness is sometimes a side effect of smooth even writing. I have track lighting with 17 LED lamps in my basement to eliminate shadows. I use tracks instead of cans to make it very easy to adjust the position of light to where I'm working. So there are at least three scientific appeals to bright light that were not covered in the article.