You're placing arbitrary values on the further values of light and darkness, while separating them as independent from one another. That is not possible. The duality begins the moment you conceive of the value 'darkness', since it cannot be conceived without its corresponding opposite. The void is not darkness. It is empty. That is what void means, but it is absolute emptiness, 'the negation of negation'.
What we call 'light' and 'dark' are just two aspects of the same reality. One cannot exist without the other.
The idea of darkness within the mind is generally thought of as the state of ignorance. Out of this ignorance comes the projection of moral values of good and evil. And so darkness came to be seen as evil, or where evil dwelt.
Beyond that, man personified the darkness as devils and demons, and the light as god and angels. These dualities exist only in man's mind as projections of his ignorance. When bad things happened to man as a result of his ignorance, he imagined some evil entity as responsible for their occurrence, or that he was being punished by a wrathful god. And so he made sacrifices, but the 'punishments' continued in the form of disease, locusts, floods, and other calamities. Finally, the only acceptable host in the eyes of his god was god himself. Of course, this is primarily a Christian view.
