I've been meaning to dig deeper into Rudolph Steiner's works since I first became aware of him a few years ago.  Steiner is an intriguing character for a number of reasons.  He was a passionate polymath, being interested and well-versed on a wide range of topics, accomplished philosopher and lecturer, founder of an alternative education system (Waldorf), and expert on esoteric matters (having founded Anthroposophy).

I was at the book store the other week, saw a book on his life and works, and decided to pick it up.  While reading the book, I saw reference to one of his famous works: Knowledge of the Higher Worlds and its Attainment.  I've been briefly skimming the book (thanks to Google Books) and found 2 great passages that resonated with me.  Steiner discusses the importance of patience with respect to the pursuit of knowledge (pg. 31).

"... no student should spend more time and strength upon these exercises  than he can spare with due regard to his station in life and to his duties; nor should he change anything for the time being, in the  external conditions of his life through taking this path.  Without patience no genuine results can be attained."

AND

"When the student seeks the path leading to higher knowledge in the way described in the preceeding chapter, he should not omit to fortify himself; throughout his work, with one ever present thought.  He must never cease repeating to himself that he may have made quite           
considerable progress after a certain interval of time, though it may  not be apparent to him in the way he perhaps expected; otherwise he can lose heart and abandon all attempts after a short time."

Wilber makes reference to the birth of AQAL (All Quadrants, All Levels) in his work The Marriage of Sense and Soul - Integrating Science and Religion (pg. 63):

"It is fascinating that both premodern religion and modern science have a defining hierarchy, and both of them are composed of enveloping nests of increasing embrace (development that is envelopment).  And yet, these two major and extremely influential hierarchies never quite agree with each other.  Tantalizingly, they seem to talk about the same thing (a graded series of realities), yet their major terms never really match up.  Clearly, if we could find some way that these two hierarchies were genuinely related to each other, we would have teken an important step toward the hoped-for integration of premodern and modern.

In researching this problem, I did an extensive data search of several hundred hierarchies, taken from systems theory, ecological science, Kaalah, developmental psychology, Yogachar Buddhism, moral development, biological evolution, Vendanta Hinduism, Neo-Confucianism, cosmic and stellar evolution, Hwa Yen, the Neoplatonic corpus - an entire specturm of premodern, modern, and postmedern nests.  After I had collected several hundres hierarchies, I tried grouping them in various ways, and I eventually noticed that, without exception, they all fell into one of four major types.  These (are the) four types of hierarchies - which I call the four quadrants..."