Some ACIM terms defined

REALITY: The entire unlimited expanse of God, and the interior contents of God which he hosts within his being. Everything within it is eternal, permanent, changeless, deathless and unlimited. It can only be KNOWN directly. This does NOT include ANYTHING that is lacking these immortal attributes. Anything impermanent, temporary, changing, attackable, mortal, is not a part of reality and is essentially impossible.

ILLUSION: The seeming OPPOSITE to reality. It is unreal, a dream of mortality, a fiction, untrue, false, a state of denial, and something you made up. Everything within this illusion is false and unreal. This includes all the forms of error, all sin, all sickness and death, all bodies, all planets and galaxies, all physical objects, all of perception - true and false alike, even the real world and the forgiven world.

FALSE PERCEPTION: A view that you have ABOUT something which is an illusion. Any illusion (body, planet, whatever) is NOT recognized for what it actually is. It is thought to be something IT IS NOT. It is a lie about a lie. A double negative. It's the belief that an illusion IS REAL, that false things ARE TRUE, and that the physical world IS GOD. This is what it means to be completely deceived and insane and in a state of sin.

TRUE PERCEPTION: A view that you have ABOUT something which is an illusion, but which entails RECOGNIZING the illusion for what it actually IS, and NOT for what it appears to be. It is illusions seen without deception. It is ACCURATE perception. It is a straight-on honest recognition that an illusory thing is a dream, and is not reality. It OVERLOOKS the illusion by seeing THROUGH its lies, is not deceived by it, and sees BEYOND IT to the light of reality.

THE FORGIVEN WORLD: This is the world of false perception, which is the world of sin, which includes bodies and flesh and bones and planets and galaxies and stars, but viewed from true perception. It is forgiven because ITS LIES are overlooked, its temptations do not work, and its DECEPTION is recognized as something false. It is a complete recognition that the world you made in false perception IS false, and that it IS an illusion, and IS NOT REALITY. This is seen with a LOVING perception, but nevertheless includes the awareness that earth is fundamentally unreal. "A world forgiven cannot last. It was the home of bodies."

THE REAL WORLD: The use of true perception sees PAST or through the forgiven world, OVERLOOKS it (does not see it), and sees beyond it and beyond the body. It looks upon the face of christ in heaven, and so is the use of perception to peer OUTSIDE of the illusory realm. It is therefore an ILLUSION ABOUT HEAVEN, and an image of heaven. It is symbolic of reality, but is not reality itself. It reflects heaven's nature but is once removed. And even the perception of the real world is a dream that will end.

ATONEMENT: Is the same thing as true perception and forgiveness. Atonement, true perception, forgiveness, salvation, etc are all the same thing. They are a SYMBOLIC state which represents heaven's laws and nature. It POINTS TO heaven and asks that you accept heaven's truth. Only heaven's truth is true, and NOTHING ELSE is true. Earth is false and is not true. It is vigilance for the kingdom, that ONLY GOD'S REALITY IS REAL.

HEAVEN: Another term for God's Kingdom or his one son/creation/sonship. It's the collection of souls that God established within his being IN reality. Thus they have all the attributes OF reality, including permanence and immortality. It is the reality that you find yourself waking up into, when you wake up FROM the illusory world of space and time. "Only heaven remains." "Heaven remains your one alternative to the strange world you made (earth)."

EARTH: The false world you made in separating from and opposing reality. It is hosted within spacetime, which is a false belief. Earth depends entirely on both space and time for its three-dimensionality, its keeping its atoms from colliding with each other, and its seeming growth and decay. It is not reality because it has no permanence of any kind. "The time will come when all things visible will have an end." "As the world spins into the nothingness from which it came." Earth seen AS earth is false perception. Earth seen AS the forgiven world, is a recognition of its unreality. Either way earth is opposite to reality.

SPACE: The idea of the total opposite to God's omnipresent reality. God is everywhere and all of him is everywhere. Space was devised as an attack on God, to be opposite to this idea. It is the idea that nothing is whole, the whole is not anywhere, nowhere is whole, nothing is everywhere and everything is nowhere. It is the idea that God who is everything does not exist. And all energy, matter, quantum fields and whatever, depends on it entirely to seem to exist. It is an illusion, and once it goes, the whole physical universe goes with it.

TIME: The idea of a total opposite to God's eternal nature. Eternity tells you that everything always remains the same forever. That you have eternal permanence and can never be changed or decay or be sick or die. That you are always you. Time is the opposite of this. It's the notion that you are not what you were previously, what you used to be is lost, and what you are now is going to be changing into something else. It's the idea of the complete destruction of eternity and that everything must die. It is an attack on God's reality and when time ends everything that grows and changes will be gone forever.

WORLD: This one has some controversy but basically, a world is just some realm or existence, be it a real existence or an imaginary one. The real "world" which God created is his Kingdom of heaven which is the sonship, and nothing else. The world WE made is the illusory world of space and time which houses planets and galaxies and is completely OPPOSITE in its nature to God's world. There are only two worlds. There are not three worlds. There are only true because there are only two logic states - reality and unreality. God's true world is the only truly created world. Our made-up world is a temporary illusory world which God could never even conceive of creating.