Answer: Light is what we perceive. We cannot say anything about something that is beyond us. This means we cannot talk about the Creator before He is clothed in us. What exists and is not clothed in us is called Atzmuto (His Essence), and we do not give Him any particular name.
Is there Light outside of us? This I do not know. I can say that it exists only when it exists inside of me.
We talk only about what we attain because Kabbalah is a science. What we attain in our internal “software” is what actually exists.
From the Kabbalah Lesson in Russian 3/19/17