“…This alternative dimension, which was based on descriptions of personality deviance (unrelated to E or N; see later) that might occur prior to the onset of schizophrenia or among biological relatives of schizophrenic patients (e.g., Slater, 1953), was termed S or Insensitivity. Subsequently, the inverse of the EPQ P factor was found to include a separate dimension, called G or Orderliness, which, according to Tellenbach (1961), Maier, Lichtermann, Minges, and Heun (1992), and other investigators, appeared to describe a single component of the premorbid personality configuration (also characterized by high N) that determines the probability of being affected by unipolar depression and, perhaps, bipolar disorder (Van Kampen, 1997). Indeed, recent research by Sakai et al (2009) has very much elucidated the causal role played by this and similar dimensions in the onset of depressive symptoms.…”