The Power of Positive Thinking shows, organized the American Foundation of Religion and Psychiatry, and co-founded the spiritual newsletter "Guideposts" with his wife, Ruth Stafford Peale. "The Power of Positive Thinking" was published in October 1952 and continues to be Peale's most widely read work. It lived on the New York Time's best-sellers list for 186 weeks, 48 of which were spent in the No. 1 nonfiction spot. The book sold more than 5 million copies worldwide — 2.5 million from 1952 to 1956 — and was eventually translated into over 40 languages. Other books published by Peale around 1952 include "The Art of Real
Positive adult development and Langer (1990). Four postformal adult stages of development beyond the formal stage have been discovered in a wide variety of domains. The total number of stages across the life span now stands at 15. Periods and Seasons have been described. For critical discussion of term postformal thinking, see Kallio (2011). She claims that highest forms of adult cognitive development (as part of adult positive development) can be called as integrative thinking (i.e. integrating several different psychological domains as emotions, cognition etc.). A number of edited books were written on the topic of positive adult development in the 1990s (Commons,