“Just as we are convinced of the substantial existence of this world, so does the world above view us as a nothing, seeing itself as the genuine reality.
In illustration of which there are certain clever drawings with subtly shifting foregrounds and backgrounds; the viewer is never quite sure which is the real picture.
So too, the world below and the world above can be portrayed as a cosmic optical illusion each fitting perfectly into the other and providing us with either the real against the unreal, or the front against the back, constantly changing places in our consciousness.
It is not only the old problem of subjectivity of vision, it is a recognition of the existence of a higher and a lower, a world of the graspable and a world of the ungraspable, being and nothing.”
–Rabbi Adin Steinsaltz
Rabbi Adin Steinsaltz, The Candle of God, “Implications of the Menorah,” p.341-342