The Complex Dynamics of Wishful Thinking: The Critical Positivity Ratio


Brown, N., Sokal, Alan D. and Friedman, Harris L. 2013. The Complex Dynamics of Wishful Thinking: The Critical Positivity Ratio. American Psychologist. 68 (9), pp. 801-813.
AuthorsBrown, N., Sokal, Alan D. and Friedman, Harris L.

We examine critically the claims made by Fredrickson and Losada (2005) concerning the construct known as the “positivity ratio.” We find no theoretical or empirical justification for the use of differential equations drawn from fluid dynamics, a subfield of physics, to describe
changes in human emotions over time; furthermore, we demonstrate that the purported application of these equations contains numerous fundamental conceptual and mathematical errors. The lack of relevance of these equations and their incorrect application lead us to
conclude that Fredrickson and Losada’s claim to have demonstrated the existence of a critical minimum positivity ratio of 2.9013 is entirely unfounded. More generally, we urge future researchers to exercise caution in the use of advanced mathematical tools such as nonlinear dynamics and in particular to verify that the elementary conditions for their valid application have been met.

Keywordspositivity ration; broaden-and-build ratio; positive psycholog; non-linear dynamics; Lorenz system
JournalAmerican Psychologist
Journal citation68 (9), pp. 801-813
PublisherAmerican Psychological Association
Accepted author manuscript
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Publication dates
Print15 Jul 2013
Publication process dates
Deposited19 Aug 2013
Copyright information(c) 2013 American Psychological Association. This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.
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