Darkness

(1) An absence of light.

(2) A force of evil; a misqualification of light.

Pallas Athena explains the difference between these two usages of the word:

Yes, light exists and darkness exists. Some men have tried to simplify this concept by saying that darkness is an absence of light, whereas others have equated darkness with evil, seeing it as a virulent force that seeks to overthrow the light. There are elements of truth in both statements. For example, in the mind and being of man, the vacuum that is referred to as darkness, or a lack of light, is not a positive force; it is not a negative force; it is not even a misappropriated force; it is simply an absence of the realization of light’s potential.

On the other hand, that darkness which results from the misqualification of light, from its conversion into Darkness, is of another type, which can be categorized as a negative force or a positive evil. That there are various types of darkness was clearly pointed out by the Master Jesus in his exclamation “If therefore the light that is in thee be darkness, how great is that darkness!” This may be read as a question by the earnest disciple: How great is the intensity of the darkness in me? Is it a misqualification of light, an energy veil, or is it an absence of light, a lost opportunity? How great an impediment is this darkness to my understanding of truth?

Light is not at war with darkness, nor are good and evil engaged in mortal combat. Light, unaware of its opposite, fills the darkness and transmutes the energy veil just as the presence of good consumes on contact all that is unlike itself.

Sources

Mark L. Prophet and Elizabeth Clare Prophet, The Path of the Higher Self, volume 1 of the Climb the Highest Mountain® series.