" evil is nothing else than absence of goodness, just as darkness also is absence of light. For goodness is the light of the mind, and, similarly, evil is the darkness of the mind. Light, therefore, being the work of the Creator and being made good (for God saw all that He made, and behold they were exceeding good(8)) produced darkness at His free-will. "

― John of Damascus , An Exact Exposition of the Orthodox Faith