Existential anxiety is a special case of anxiety in general that does not respond to any form of specific treatment, and is based on the philosophy of existentialism, which focuses on the identity and meaning of the self. In this regard, someone suffering from existential anxiety is said to be trapped in a unending cycle of speculation about the meaning of their life, the contemplation of their inevitable death, and the nature of their place in the world around them. Ultimately, existentialists are concerned with the fragile nature of human existence and the limits of what can be experienced or accomplished in an unpredictable life span.
The marked difference between normal anxiety and existential anxiety is in the fact that the former lends itself to clear-cut treatment and the latter does not. An elementary fear can be treated by determining on what dangers it is based, understanding that such dangers are temporary, and finding appropriate methods to cope with or distance oneself from such risks. The existential attitude is instead based on what is termed a “free-floating terror” that has no discernible cause, is all-pervasive, and can effectively be a permanent condition for the individual. Because of its expansive nature, existential anxiety tends to exaggerate ordinary circumstances or fears to the extreme and generate phantom fears of monsters and other dangers created in the mind. Psychologists, however, believe that almost all existential anxiety is rooted in two fundamental human conditions — the fear of death and the fear of unknown events in the future in general.
Philosophers also attribute existential anxiety to the concept of the self being a fluid one. The self can be seen as having an identity based entirely upon its physical circumstances and relations to others, and, since these conditions are always in flux, the identity of the individual does not have a firm foundation of meaning. This can be seen in a positive light as well, where it liberates people to redefine their place in the world and choose a new identity. The basic weakness and strength of human beings that causes existential anxiety, therefore, is the nature of human freedom and individual existence, which allows for abrupt changes to one's purpose and reason for living.
It has been said that human beings are unique on Earth as being the only creatures that contemplate their own existence or place in the world. The practice reflects a deep-seated insecurity and conflict in the human mind, where there is a desire for permanence and meaning in life while being immersed in a reality of change and loss. The philosophical thinking of existential anxiety is believed to have given rise to all the world's religions as well as the scientific pursuit or desire to intimately understand the nature of physical reality. Existentialism is also focused on the dichotomy that exists between people wanting to express their innate uniqueness, and, at the same time, be welcomed and accepted by the group. One of the most profound expressions of this is in the desire by individuals for the long-term experience of romantic love.