God called the light "day," and the darkness he called "night." And there was evening, and there was morning—the first day. Genesis 1:5Without night, when would we rest? While people do sleep during the daytime, it's not the optimum time for rest. When darkness falls, when we can't see into the night, we settle into a routine that involves sleeping. Winter is like that too. It's a time for nature to sleep and prepare for spring.
All that aside, consider not seeing for a moment. Sometimes I listen to music with my eyes shut. Without the distraction of all the things I can, I am able to concentrate on the music better. Seeing with the heart can be one of the most difficult things to accomplish, but also one of the most rewarding. The Celtic Christians asked God to give them his eyes for seeing, an ability to view others and the world around the way God views them. And for that, you do not need physical eyes.