This I think is a profoundly clear and definitive statement about the Course's core metpahysics. "What is the world?":
"The world is FALSE PERCEPTION. It is BORN OF ERROR, and it has NOT LEFT ITS SOURCE (error/sin). It will REMAIN NO LONGER (must disappear) than the THOUGHT WHICH GAVE IT BIRTH (sin/error) is cherished.
When THE THOUGHT OF SEPARATION has been changed to one of true forgiveness, will the world be SEEN in quite another light (re-interpreted, translated, looked at WITH a different value system, BUT STILL RECOGNIZED AS AN ERROR); and one which leads to truth, where ALL THE WORLD MUST DISAPPEAR and all its errors vanish. Now its source (sin) has gone, and ITS EFFECTS (the world) ARE GONE AS WELL."
Note that it does not say false perception is ABOUT the world. THE WORLD ****IS**** false perception. Falseness is built into it. The world IS a misperception. It is a mistake. The SIN it is made of, was a condemnation and attack on God and His Son. The ATTACK, has to be forgiven, which means the WORLD, has to be LET GO.
Note that it says, the world is BORN OF ERROR. "All forms are forms of error". Which means it was made BY MISTAKE. It is AN ERROR. "The body's eye look upon forms of error and do not see past them."
Note, that it says the world is SEEN **IN** ANOTHER LIGHT, which does not necessarily mean at all that the world STOPS being a form of error, OR a mistake. It merely means you LOOK AT IT IN A DIFFERENT WAY, with a different vantage point, which overlooks the SIN, and recognizes you were JUST MISTAKEN to make this world of sin, and it HASN'T HAPPENED and is forgiven. THE WORLD HASN'T HAPPENED, that is forgiveness. "There is no world", that is ATONEMENT. Only God's creation has ever really happened.
Note that it says, ALL THE WORLD **MUST** DISAPPEAR. This is not talking about your perception or your ego's view of the world. THE WORLD. Itself. Must disappear. Earth, planets, stars, bodies. All must disappear. They are MISTAKES. You can forgive mistakes. You can be loving towards He who was mistaken. You can shine light towards the mistake. But the mistaken HAS TO BE CORRECTED, which means UNDONE.