Fear is a universal emotion shared by all living beings. Perhaps it is far more pervasive in human beings because of the mind's capacity to imagine things in relation to fear. Every emotion has its origin in thoughts. If there were no thoughts, there would not be any fear. Fear is always relative, it does not exist by itself. We are afraid of something real or imaginary. If only we understand the true nature of fear, we would realize that the fear is of our own making; what is made can always be unmade.
The often-quoted words of Franklin Roosevelt: "The only thing we have to fear is fear itself" have far more general applicability than just in the context they were said. The key to overcome fear is to understand its nature. This is, of course, true for all emotions. The first step in using emotions to our advantage instead of detriment is to know them.
From a psychological perspective there is a mutual affinity between fear and darkness. Darkness implies ignorance in the sense that we cannot see anything, so we do not know what lies in there. This is perhaps the reason for a very widespread use of the phrase "fear of the unknown."
In reality, though, the unknown can never cause fear because fear arises from thoughts and thoughts are always in the realm of the known. The mind cannot produce anything that is totally unknown. So fear is not related to the unknown but to the possibility of the loss of the known. An extreme example is the fear of death. It is obvious that no body knows death. Knowing implies past experience and the very concept of past, present, and future vanishes with death. No one has ever come back to relate his or her experience of death. The fear is not of death itself but of losing what one has - the life and everything related to it. The fear is of the loss of the known.
The fear of loss results from attachment. In life there are different types of attachment - with family and relationships, with material possessions, with ideas and ideology, and so on. There is an inherent tendency and desire to cling on to these. The desire produces hope and the urge to dwell on "what might be." Whatever be the attachment it always brings in the possibility (and hence fear) of loss. Attachment can also be with things that are still in future like hopes and dreams. Behind every hope lurks a fear of despair.
One of the most detrimental effects of fear is the loss of capacity to think rationally. And this holds true not only for an individual but also for a society, even a nation. Fear can be collective and in this case the consequences may be disastrous. Societies and nations are made up of individuals, although in the systems prevalent today individuals do not directly contribute to the decisions and actions. Still the responsibility lies with individuals and it becomes more important to keep the fear factor from dominating the decision making process.
For an individual the most effective way of overcoming fear is to make the mind quiet. It is then possible to analyze the sequence of events leading to the fear. Once a person understands the truth behind the emotion the fear loses its grip. We cannot get rid of something unless we understand what it is. We also have to keep in mind that knowing and understanding are two different things.