Depressive disorders constitute a major health problem worldwide. From feelings of grief of daily human life to psychotic melancholic states, many different forms of depression are recognized. This fact also raises problems of classification in depressive disorders.

This presentation aims to review issues of “threshold level”, “comorbidity”, “the importance of patients’ narrative”, and “identification of core symptoms” in depression.

It is widely accepted that a common core shared in depression is anhedonia; thus, vitality of the person is lost. Mortality and vitality are the two key phenomena to consider in understanding depression.

The reality of mortality has always been a task to overcome emotionally. Human sciences and belief systems have accumulated a huge amount of theory on this issue. But, it is a crucial inevitable challenge for every human being, and this confrontation may also lead to face some sort of depressive way of being. The degree of psychological awareness and of working through the reality of mortality may determine the odds and the forms of depressive state that a person may develop. The phenomenology of depressive disorders will also be discussed in the context of mortality vs. vitality using clinical vignettes from the authors’ clinical practice to broaden the scope of discussion.