With the spread of the DSM operational diagnostic criteria, depression has been diagnosed according to the number of symptoms and their duration in recent years, and a treatment algorithm based on those factors has been created. While this ensures the reliability of the symptom assessment with some certainty, it does not lead to understanding of the individual patient's personality, pathogenic situation, symptom formation, and course as a whole.
 The typus melancholicus of Tellenbach has been trivialized as the premorbid personality of patients with unipolar depression in terms of seriousness, orderliness, and consideration for others, but in fact it is the product of long-ranging, deep thought. He actively stipulated endogenicity and placed the "endon" in a domain that exists prior to the dissociation of the physical and mental. Situations specific to the development of depression are configured at the point where the shared world and this endon intersect. It is the people with typus melancholicus themselves who induce these situations.
 These people are diligent, conscientious, and aware of duty. In work, they are accurate and have high expectations of themselves that their own work be better than average. For them, situations with significance in pathological development are the pre-melancholic constellation of includence (Inkludenz) and remanence (Remanenz). Includence means engaging with a premorbid affinity for order and confining oneself within limitations. Remanence is being left behind by one's own high expectations of one's performance. When these two situations come to a head and the individual with typus melancholicus caught in this self-contradiction has no way out, melancholy occurs with changes in the endon.
 Behind the acceptance in Japan of Tellenbach's theory of pathogenic situation, which is clearly distinguished from conventional temperament theory, is the "immodithymia (shuchaku-seikaku)" theory of Shimoda. Tellenbach himself pointed out the commonality between fixation on order and tenacity (shuchaku). In as far as the pre-melancholic constellation mentioned above is detected in other personalities including immodithymia, Tellenbach's thought is not outdated at all but makes a significant contribution to the understanding of patients with depression today.
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