How to differ fears

There are a lot of classifications of fears in the modern psychology. One of classifications divides fears in sociological, biological and existential fears.
The biological fear is fear that is directly connected with the threat of dieing. The social fears are connected with the fear to loose the social status and the carefulness in society. And the third group is connected with the essence of every person that is proper for all people.
Following this classification, the fear of the fire refers to the first category of biological fears. The fear of public performance refers to the second one that is social fears. And the fear of death falls into the third category.
But there are also a lot of subcategories and fears that refer to several groups at the same time. They may be referred as to one category as to another and sometimes to all three categories. That is why the classification needs to be changed. For example the fear of diseases is the biological fear on one hand but on the other hand this fear is social because every disease is isolation from society, the decrease of benefits, suffering, divorce and poverty. That is why this fear is something intermediate between two groups.
In fact every fear has characteristics that refer to every category but one of them is dominative, and on base of this main feature the fears may be classified according to this principle.