The two trees are shown in the diagram below (Working on the left and Perfected Tree on the right)
In the Qabalah tradition both trees are important. To understand their differences we must understand the "fall" as a mystical allusion. By the diagram itself, we can see that the Perfected Tree is symmetric and the Working Tree has a hole in it that might have been caused by a drop in the central column or by the lower seven sephiroth shifting down a space. Tradition, however, tells us that the lowers sephiroth, Malkuth was the sphere that fell out of the hole that is called Daath or Knowledge in the Working Tree.
The Golden Dawn considers this the Gate of the Abyss, whereas the ancient Hebrew text Sepher HaShemoth or "Book of Names" notes (according to the Work of the Chariot site) that the Abyss is at the path between Kether and Binah, whereas the Gate of Daath is called the Wall of Fire, and is the path between Geburah and Chokmah on a specific pathworking format called the Way of the Wizard (see diagram below).
In Paths of the Middle Column of the Tree no such challenge is denoted. What is described is that the Perfected Tree denotes the embodiment of a Revelation, which places the "fall" as an illusion. Daath is what is required to correct the fall. Daath is not intellectual knowledge but Gnosis as the state of realization that affirms the unity between microcosm and macrocosm, the unity of self and world, the unity between creator and creation. Gnosis is the lived state of the world embodied within our beings in synthesis with the state where we seem to exist within the world.
Mystics traditionally reject the state of separation for the state of internalized union with the All. Thus, the outer world receeds as an illusion with respect to the inner one. Some, however, believe that this is a compromise and that true realization involves a synthesis of living in the world and the world living in you (by "world" I mean manifest reality and the essence of reality transcending manifestation).
In the Sepher Yezirah the ten sephiroth are called ONE. They represent a singular synthesis of experience of embodiment of becoming. When the Tree is thus embodied, the world transforms right along with us, because our experience of it transforms. This synthesis is not possible in the Working Tree because it represents the fruites of the Knowledge of Good and Evil. The Working Tree is the one prohibited by YHVH, whereas the Perfected or Original Tree is the one meant for Adam and Eve.
To understand the nature of this commandment in Genesis, we must understand the meanings of the Hebrew words translated as Good and Evil. The words are correspondingly Tov and Ra, Tov being Tayt.Vav.Bayt and Ra being Resh.Oyin. Calling these two words respectively "good" and "evil" is imposing a qualitative bias that prevents really understanding them. To understand them we must look at their serial organization of letters.
Tayt or Teth depicts an X in a circle in proto-sinaitic (the original Hebrew alphabet), and depicts a coiled serpent or structuring and weaving force. It is the last letter in the one's row of the aleph-beth, and denotes the final stage before manifest existence. The serpent in the basket represents the force that weaves together to create manifest experience. Yod is the first letter representing manifestly percieved causality, depicted by the arm glyph.
The first nine letters are pre-manifest forces and principles, Teth being the most complex of them, the force that leads to manifest action. Vav is the principle of connection and fertilization (represented by the peg or phallus), and Bayt or Beth the principle of containment represented by the house, vulva or tent. The word Tov is telling us that the structuring/weaving premanifest force fertilizes containment (the principle formation). This is a natural process, and good because it is so.
Ra, on the other hand, represents Resh as the system of consciousness represented by the front of the head. Resh has a numeric value of 200, where 2 represents containment and the double zero of the hundreds represents a universality or collection of elements forming what we would today call a System. The ancient Hebrews viewed human awareness as a collection of effects, in other words, effects that contained and related one form or pattern to another. This is not so different from how information systems are viewed today.
Oyin is depicted by the eye, and it is numbered in the tens. The tens signify manifest dynamics, principles that are directly tangible to us and our human perception. They are neither abstracted forces as the letters belonging to the row of single digit numbers nor yet complex projected systems of interactivity as the letters belonging to the triple digit numbers. The number of Oyin is 70, where 7 represents division, distinction and definition, depicted by the glyph of the sword. The number 70 represents the manifest outcome of the force of distinction, and the eye tells us that this outcome is discrimination of one thing and outcome over another.
In Genesis we are told that God gave Adam the power of naming. To name Adam had to tell one thing from another, and hence hold the power of the eye. However, this power was both God given and God driven, hence natural. It was a result of Tov, or a natural causation for Adam. Ra, on the other hand, qualifies Oyin with the powers of human consciousness as something distinct from natural process. What Ra, therefore, represents and has been judged as evil is the human capacity for artifice, for naming and defining and interacting with reality on terms purely generated within human consciousness independently of divine nature.
So knowledge of good and evil takes a different tone here, and this is the interpretation actually given to the words by the serpent on the tree: This is the knowledge that the human individual can make their own choices independent of their natural or divinely inspired inclinations. In other words, while Tov is God determined, and hence "good", Ra is self-determined and hence "evil". The latter conclusion, however, is a rushed judgment because it assumes a fallacy: that God-determination and Self-determination are in opposition to each other.
It also assumes that every self determined choice is in opposition to divine will, whereas self determination really implies that it can be. This also leads us to view Tov in a way that does not completely justify its equation with good: Divine Will in other words predominated because there was really no Human Will. Human beings knew what was right, but had no comparison with what was wrong. Without that comparison they could not truly be one with Divine will, only acting instruments of it, similar to animals in obedience to their natures, automatons of God, and caricatures of God because they were in divine image and likeness.
So as some Hebrew scholars propose, the decree not to eat of the Tree of Knowledge of Self-determination was a challenge to the first humans to make up their own mind, to weigh the consequences of their actions according to their own comparisons and to act because they choose to act, and not because God wills it or some blind action-reaction natural principle. Then these human beings would be challenged through their own experience to realize what God wants is right, but also more (something that the serpent also implied).
Human beings could transcend God as YHVH Elohim because they could embody God as themselves, to be Creators in their own right taking responsibility for all they thought, felt and did. They would understand the value of the natural process, but could extend it and explore possibilities beyond it because they had that choice. The Tree of Life without the Tree of Knowledge represented guarnateed but automatic and instinctive life. The Tree of Knowledge without the Tree of Life represented a life where death and misery predominates because humanity divorced from its divine roots is no more free than humanity dependent on its divine roots.
The two trees must become one, and this is why the path of redemption is really the path of human evolution closing its own circle. The judgmental interpretation of the Fall as punishment reflects the view of a people cursing their capacity for self-determination, reflects elements of society posing as sources of wisdom that either claim to be representatives of divine will with everyone else as the automaton of that will or so discouraged with the results of human self-determination that they completely shut off the one logical alternative: divine embodiment within human self determination.
In fact these elements of society that interpreted the fall as punishment also contributed for the wisdoms of divine realization as transcendent self determination to be defined as taboo and forbidden to the whole of human society. Within that context, however, other elements promoted the knowledge of redemption, such as what is propagated through Qabalah.
We are all self-determined, even if most of us are conditioned to be determined by selves other than ourself. It is just that when consciousness is divorced from its divine roots, other elements come in to insure human response is still the response of an automaton. Those factors may be distortions of natural instinct, the results of being starved of our life-force birthright or the conditionings of other people and their "ideals".
We have thus become slaves to our god-given desire to be distinct from divine will, and thus slaves to what is called Satan, the personification of that desire, which is really a personification of the evolutionary force geared to transform us from automatons to independent creators in our own right. Satan is the initial impulse and Christ the final return to integrate our individualized humanity with our divine roots. They are actually one and the same when the Trees of Knowledge and Life also become one. Satan is redeemed because Satan awakens as Christ and Christ manifests on earth because he/she remembers they have always been there as Satan, and that we human beings have always been both.
This is heretical to Christian and Hebrew dogma, but it does reflect the wisdom of Qabalah. We start with the Working Tree because that is where we are. We move through the tree until the Gate of Daath. This is the Gate to an abyss as long as we do not redeem Daath with Malkuth in that position. Malkuth in the position of Daath is what fills the void of the fall so we can move on and realize that the trees of Knowledge and Life are one and the same, and embody and live that realization.
Daath, in Hebrew is written Daleth.Oyin.Tau. The Tau represents the crux of the matter, and its number is 400 in comparison to the 4 that represents Daleth. The glyph of Tau is an X, while that of Tayt or Teth (the first letter of the word Tov) is an X in a circle, or one contained to weave manifest outcomes. Tau is the seal or essence of anything, a complexity of responsiveness that is the nexus of a crossroads of causalities. Tau is the seal or signature, the condensed meaning of something.
Daleth is a membrane, a vibrating field of responses, and in this case it represents the distinctions of the eye, distinctions that move directly to the heart of the matter (Tau). Daath is what connects us to everything through experience of its distinctiveness. This is knowledge in the carnal as well as the gnostic sense. What is the Tau or crux of the matter here? It is Tov and Ra. Daath puts Tov and Ra in the prespective that permits synthesis, with Tov being thesis and Ra being antithesis.
This synthesis is one with the emerging awareness that Malkuth is within us, and transforms the Working Tree to the Perfected Tree.
Then we may begin our true integration of the Tree, and as we awaken the powers of its paths and qlippoth (sephirothic shells), by bringing them to life, we do so as we have always been meant to do so: in a naturally self-determined manner.