Div texts (2009-2014) about this figure. May seem speculative, or elitist, but relates to research by first and foremost theologian and developmental psychologist James D. Fowler. Psychologists such as Abraham Maslow and Erik H. Erikson has contributed to the genre of "stadium theories". I have mainly been interested in Fowler and his research on FFA believing Christians. The texts contain many different designations for the vertical and horizontal axis, levels and types, and the figure itself, but by and large it is the same basic ideas. Will try to compile and transpose the best ideas into ngt uniform later: Dealing with the paradoxical What should the types be called? Inventorium Thoughts about the axes in the figure A second boldness ASC Levels and types in the figure. Reflections and comparisons with other systems (PDF)