In his most important contribution to the Heidelberg school, a founder
of existentialism critiques the scientific aspirations of
psychotherapy.
In 1910, Karl Jaspers wrote a seminal essay on morbid jealousy in which
he laid the foundation for the psychopathological phenomenology that
through his work and the work of Hans Gruhle and Kurt Schneider, among
others, would become the hallmark of the Heidelberg school of
psychiatry. In General Psychopathology, his most important
contribution to the Heidelberg school, Jaspers critiques the scientific
aspirations of psychotherapy, arguing that in the realm of the human,
the explanation of behavior through the observation of regularity and
patterns in it (Erklärende Psychologie) must be supplemented by an
understanding of the "meaning-relations" experienced by human beings
(Verstehende Psychologie).