The psychobiological theory of temperament and character: comment on Farmer and Goldberg (2008)

The revised Temperament and Character Inventory (TCI-R) is the third stage of development of a widely used multiscale personality inventory that began with the Tridimensional Personality Questionnaire (TPQ) and then the Temperament and Character Inventory (TCI). The author describes the third stage of the psychobiological theory of temperament and character; empirical tests of its predictions from genetics, neurobiology, psychosocial development, and clinical studies; and empirical findings that stimulated incremental changes in theory and test construction. Linear factor analysis is an inadequate method for evaluating the nonlinear and dynamical nature of the intrapsychic processes that influence human personality. Traits derived by factor analysis under the doubtful assumption of linearity are actually heterogeneous composites of rational and emotional processes that differ fundamentally in their underlying brain processes. The predictions of the psychobiological theory are strongly validated by extensive data from genetics, neurobiology, longitudinal studies of development, and clinical assessment. The distinction between temperament and character allows the TCI and TCI-R to outperform other popular personality inventories in distinguishing individuals with personality disorders from others and in describing the developmental path to well-being in terms of dynamical processes within the individual that are useful for both research and clinical practice.