It goes through a system of different filters that weaken the Light. The filters disassemble the Light into many different forms of bestowal, which gradually weakens it until it reaches our world as a big, open hand-held fan, and it affects all of the atoms and the most elementary particles.
This is how we begin to feel this bestowal a bit in our world. First, we only feel that we exist in this world, then that we grow like plants, then we move like animals, and finally we feel it as human beings in the connection between us. This is how the Light develops our ego.
The egoistic point begins to develop its own tree under the influence of the Light from the bottom up, which is opposite to the tree of life that descends from the top down. The tree that grows from the bottom up is called the tree of the knowledge of good and evil.
The two trees complement each other and become a man. A system called man is created, as it is written, “For is the tree of the field man.”
From the Kabbalah Lesson in Russian 1/10/16