The Centaur Connection
Ken Wilber's first book, A Spectrum of Consciousness, appeared in 1977, the year of Chiron's discovery, and is credited with officially ushering in the transpersonal psychology revolution. Aptly synchronistic! According to Rowan, Wilber's early work "threw a flood of light" on the entire field of consciousness studies.
Wilber has dissected, criticized, and integrated many traditions and disciplines, from both the East and the West – including prehistory, mythology, psychology, philosophy, religion, science, anthropology, sociology, and more – to come up with an all-encompassing or integral approach to the theory of human evolution, human development, the evolution of consciousness, and the nature of the "self."
Wilber outlines a number of stages of development in what he calls a spectrum approach to consciousness. Throughout his many books, he has conceptualized this spectrum in a variety of ways, presenting numerous models, maps, and diagrams, including anything from several to 17 levels, for within each level also lies numerous sub-levels.
It is important to note that Wilber's model of the evolution of human consciousness is both holarchical (embracing holism within hierarchy, or a hierarchy of wholes) and cyclic insofar as it depicts life as constituting a curve with an outward movement and an inward movement. There are obvious limitations in attempting to represent this material on a linear table. Any attempt to distill Wilber's work carries with it the risk of omission or gross oversimplification.