The diagram shown is a generalized progress chart for most all forms of endeavour from a school trip to a farm community. Click for Brian's diagram
The idea had its earliest roots in a book by Dr. Humphrey Osmond, back in the 1960's, with the title of: Understanding Understanding. It was co-authored by others, one of which was Jerome Agel. In the book, dealing with the types of human behaviour, reference was made (more negatively than otherwise) to Carl Jung (pronounced "Yung") and his works back in the 1920's dealing with types of personalities. The four basic types, both according to Jung and according to the authors of this book were: Intuitive, Thinking, Sensation, and Feeling. The first and third were complementary, while so were the second and forth.
This lead to a hypothesis of progress that moved from "Intuition" (in the formulation of an idea), on to the "Thinking" (or analysis of whether the idea was feasible), through the "Sensation" (or the implementation of the idea, itself), and finally into the "Feeling" (or passion that would keep the idea on-going). Instead of using the original terms, the commonality of the terms was reinforced by using the newer words that all started with "Per...", and those terms are, as shown on the diagram: Perception, Permission, Performance, and Perpetuity.
As far as the Autism Community Project, the spiral in the diagram gives a hint of how far we have come, to date, with the largest part of the spiral already through the Perception stage, and moving through the Permission stage. This year, hopefully, we will be moving more through the Performance stage (involving the actual work on the project via the trail grooming, the garden layouts, and possible some crafts and other ventures). Then, to keep the idea moving, the passion for the project will move us through the Perpetuity stage (where we look back over the growth of the project) and onto the next Perception stage (where creative ideas of new venues in the project are brought forward).
As any project grows, the spiral grows with it, and the diagram is full of many spirals after many years of growth. That is not to say that all projects last indefinitely; one can see the current problems in the NHL as an example where the progress spiral came to an abrupt halt, and it could take a long time to get the spiral moving again. Often, this is a result of the spiral being moved too fast, and a crash ensues, with the need of lots of repair work. Hopefully the Autism Community Project will have a steady flow rate, and the growth with continue for many decades to come...