Today I quote from A Course in Miracles (ACIM) as a way to show why we keep coming back, life after life after life, and how we can shorten our learning time:
There is no world apart from what you wish, and herein lies your ultimate release. Change but your mind on what you want to see, and all the world must change accordingly. Ideas leave not their source…
…There is no world! This is the central thought the course attempts to teach. Not everyone is ready to accept it, and each one must go as far as he can let himself be led along the road to truth. He will return and go still farther, or perhaps step back a while and then return again.
-Lesson 132 Paragraphs 5 and 6 (p. 242-243 in my edition).