Now that is a good question, and it never occured to me to ask it! This is a bit from the link below!
The word, "spirituality" is tossed about quite a bit these days without much reference to its meaning. In this seminal project by the Association of Learners, members attempt a "scientific" exploration of the meaning of this pivotal concept. Starting from personal experience, then using the imagination to move into a vision of what the personal experience suggests about the nature of reality, they conclude with modes of living designed to apply and test their "vision," which, in effect, is the experiential research of "spirituality."