The one and only real thought system is the system of God's thinking in his mind in reality. There is really no other system of thought or function that makes sense or that is wholly sane.
If there were to be another system of thought, it would have to be completely different to God's system. So much so it would have to oppose and reject and deny and attack God's system in every way possible, in order to be different. "The world was made as an attack on God."
In the separation, we attempted to produce a second thought system. We wanted to think unlike God. We tried to oppose his will and to function in a way he did not design. We wanted to be opposite and different and dream of things that he would never think of.
What basically happened is, in our total freedom, we were able to use our freedom to try to stop being free. This is entirely within the laws of God. However, even though we're capable of trying to do this, what we find out is that it makes no sense to do it.
Trying to use will to will not to will anything, is obviously a circular logic. You need to use the very thing you are trying not to use, in order to try not to use it. At some point you'll realize that it's impossible to completely switch off will while still willing to be unwilling.
It should be obvious to us that even attempting to will against will is completely futile and pointless and cannot really produce any real effects. It's not that God prevents us from attempting this, only that when we do attempt it we are basically not making any sense. This causes us to produce what seems like a second system of thought which is based on insanity and self deception and denial.
This second system of thought, which we call the ego thought system, is a rejection of reality and truth. So it also rejects immortality and eternity and permanence and every attribute of God. This is what has produced the world of space and time and death and suffering, which are utterly impossible in God's reality.
So we invented, or tried to invent, a secondary system or way of thinking, which is referred to as a "lower order reality". It seems to have reality only in that we attempt to believe it is real, when it isn't. Or that we believe it is possible when it isn't. Or that we think it makes total sense when it doesn't. It is the ego thought system, and everything in it is contradictory and a lie.
These are the only two thought systems that are possible, and only one of them is ultimately possible. The second thought system is really an attempt to believe that something completely impossible is possible. Notions of living without God, of suffering, of mortality, or impermanence, are all impossible in God. Believing in them and trying to produce proof of them is self deception.
The only task then is the undoing of the second thought system entirely, which is the atonement. It is the cancelling out of the ego and the entire lower order reality, so that minds return to sanity and the acceptance of only God's thought system.
Only in God's system is it accepted as obvious that there is no point whatsoever in even attempting to oppose free will. Only in his light is it evident that when you try to use creation to not create, or to will nothingness, or to be something you can never be, you are trying to do something that you will never really do. And only in make-believe and wishful thinking could you ever believe that you are doing it.
To return your awareness to the one and only higher order reality, which is the only true and self-consistent reality, you first go through a phase of correction and purification. This means learning to admit that the false world is false, and that unreality is not possible. It's the process of exchanging the laws of spacetime for the laws of God. And of re-aligning yourself with the one and only truth.
At the pinnacle of this process, the mind is at the heights of consciousness and perception, which becomes inclusive and closely reflecting the way God thinks. It is still within the realm of illusions and unreality, but the system of thought is exposing itself to the light of heaven.
Eventually when this is complete, and a person is fully willing to accept that only thinking like God makes any sense, only his truth is true, only his laws are applicable, and nothing else is possible, atonement is fully accepted. In accepting it, the mind wakes up to the one thought system of God and the second thought system completely vanishes.
No-one can truly believe in both thought systems at once. That is why when you enter into belief in the lower order reality you become blinded to heaven. "You cannot behold the world and know God." "You cannot see two worlds." "The world you see must be denied because sight of it is costing you a different kind of vision."
Upon awakening to reality, that which seemed visible in the lower order becomes invisible to you. And that which seemed invisible in heaven becomes fully seen. Awareness returns as the knowledge of total reality returns to the mind, and the illusory world of contradictions disappears from sight.
"The world stands like a block before Christ's face. But true perception looks on it as nothing more than just a fragile veil, so easily dispelled that it can last no longer than an instant. It is seen at last for only what it is. And now it cannot fail to disappear, for now there is an empty place made clean and ready. Where destruction was perceived the face of Christ appears, and in that instant is the world forgot, with time forever ended as the world spins into nothingness from where it came."
"God made no contradictions. What denies its own existence and attacks itself is not of Him. He did not make two minds, with Heaven as the glad effect of one, and earth the other's sorry outcome which is Heaven's opposite in every way."