In many instances the terms light and darkness are used to describe discernable or moral situations. Many people object to such discernments claiming they frequently tends to become unjustified moral judgments. However, if such discernments are made without bias both the pros and cons are equally considered. In metaphysics darkness is not to be confused with night since they are both distinctly different terms. Darkness should not be equated with evil since it is a positive natural force just as light is.
Night is a lunar force just as darkness is a cosmic force.
The commonality that they share is the absence of their opposite force, or light.