A traditional view in psychiatry concerns the intimate relationship between personality disorders and primary mental disorders in a spectral model. Psychic functions with common roots might play a role in personality and psychosis or other disorders, probably not only in terms of deficits but also balance or proportions among them. Personality characteristics in connection with endogenous or functional psychoses are described, such as the sensitive and melancholic types. Concepts derived from psychopathology, namely schizoidism and syntony, which involve psychosis and personality, seem related to pivotal frameworks in cognitive sciences comprising the so-called 4Es. When adopting a continuum view of mental disorders, they behave in a unitary or systemic configuration, corresponding to endogenous-functional dispositions interacting with the milieu and composing personality.