So, the assumptions and clinical strategies that dominated the 20th century primarily derived from Freudian or psychodynamically derived approaches began to be severely challenged with the advent of Cognitive-behavioral therapies beginning in the seventies and now that perspective is without doubt the reigning one in academic and clinical circles. Positive Psychology moves the paradigm further down the road by its emphasis on the power of energizing the strengths of human individuals to, as Frederickson says, broaden and build individual personalities and community social enterprises. Barbara L. Fredrickson, The Value of Positive Emotions American Scientist. Volume 91 330-335 Essentially, the evidence is mounting from the many studies launched by the Positive Psychology movement to indicate that it is not only totally unnecessary to address the negative or pathological dimensions of human problems in most cases, but that to focus on them in any way only tends to degrade the broadening and building process.

It is at this point that complexity theory enters into the picture as a theoretical lens to help explain and support this controversial from the perspective of the last century’s assumptions way of viewing human potential. Of course, an emphasis on the positive can be found in earlier thinkers and clinicians such as Maslow, Rogers, even Adler etc., but their intuitions never were able to challenge the existing paradigm because there were no convincing evidence based studies to support them in the way that Positive Psychology has amassed and continues to amass large amounts of data from well constructed studies.

Essentially the question that has been raised by the success of some of the PP models and their associated interventions is: they work, but why and an important connecting question which we will explore further one how do they work? Complexity theory seems to speak well to the “why” question, whereas brain based understanding of mental functioning may well speak lucidly to the “how” question.