On the surface level several causes of different types of fears can be pointed out but if we go deeply we can convert all these cause into the following root causes ..if we are depending on external objects and people for out existence and feeling of self worth , we then generate fear by anticipating the loss of that object . without a habit of dependency there could be not fear. We would then allow objects and experiences to come and go without trying to cling to them. But when we feel the deep dependency on something we are inevitable afraid of losing it . whatever we feel that we must have is what we fear losing. Feeling of separateness is one of the root cause of our fear. Our sense of separateness from each other and from god. We remain unaware of our natural interconnections with each other and experience ourselves as individual egos separate from each other .whatever we se as separate from ourselves inevitable becomes a source of fear .Disbelief in god and cosmic order is also another major cause of fear. If we don’t believe that there is a ruler of the world who is running world according to some cosmic order and divine laws .feeling of self inadequacy is also create fear. Many people think that they can’t do what others do. The don’t have enough confidence and capability and consider themselves as worthless persons.