Many religions have some form of eternal bliss or heaven as their apparent goal often contrasted with eternal torment or dissatisfactions. The source of all mentally created dissatisfactions appears to stem from the ability to compare and contrast experiences and find reality as one is living it to be less than ideal. Many religions believe this was caused by man eating of the forbidden Tree of the Knowledge of Good and Evil. Man's eyes were "opened" to know the distinction between good and evil(Genesis 3:5). The solution is to seek out ways to either make experienced reality conform to the ideal and/or to lower expectations to the level of the experienced.[citation needed] When one can live in the moment with expectations in harmony with experiences one has achieved the greatest mental contentment possible.[citation needed] Variants of this pursuit are found in many religions and manifest in forms of meditation and prayerful devotions.

The American philosopher, Robert Bruce Raup wrote a book Complacency:The Foundation of Human Behavior (1925) in which he claimed that the human need for complacency (i.e. inner tranquility) was the hidden spring of human behavior. Dr. Raup made this the basis of his pedagogical theory, which he later used in his severe criticisms of the American Education system of the 1930s.