Emptiness comes as the first of the three contemplations. All things are looked upon as empty. Then follows delusion.
Although it is known that they are empty, things are not destroyed, but one attends to one’s affairs in the midst of the emptiness.
But though one does not destroy things, neither does one pay attention to them; this is contemplation of the center.
While practicing contemplation of the empty, one also knows that one cannot destroy the ten thousand things, and still one does not notice them.
In this way the three contemplations fall together. But, after all, strength is in envisioning the empty.
Therefore, when one practices contemplation of emptiness, emptiness is certainly empty, but delusion is empty also, and the center is empty.
It needs a great strength to practice contemplation of delusion; then delusion is really delusion, but emptiness is also delusion, and the center is delusion too.
Being on the way of the center, one also creates images of the emptiness; they are not called empty but are called central.
One practices also contemplation of delusion, but one does not call it delusion, one calls it central.
As to what has to do with the center, more need not be said. ~Carl Jung, Psychology of Yoga and Meditation, Page 252