Though it is a so called metaphysical subject...
Though it is a so called metaphysical subject, for two reasons it also comes under the category or practical and social questions. The first reason is that man’s way of thinking about this question affects his practical life and social attitude. It is obvious that the spirit and attitude of a man looking at himself as a being subject to inexorable determinism, is different from those of one who believes that he has been created free and hence he is master of his destiny.
Generally speaking, most of the philosophical questions do not affect the spirit, attitude and actions of man. The practical attitude and the social spirit of a person are not influenced by such questions as the temporal eternity or transcience of the universe, the finiteness or infinitude of its dimensions, the system of causation, the theory that many cannot emanate from one and the identicalness of the essence and the attributes of the Self-existent Being.
The second reason is that the doctrine of fate and destiny, despite its being a personal belief, comes under the category of the questions of universal application, for the number of people who are in search of its solutions is very large. It is one of those questions which engage the attention of nearly all those who have some capacity of thinking over general questions.
Everybody is naturally interested in knowing whether he is at liberty to determine his course of life or it has already been irrevocably determined by his fate. The scope of other philosophical questions is limited. They are only a matter of personal and private interest and do not attract such a general attention. From these two view-points this question may be included in the category of practical, universal and social problems.
In olden days attention was seldom paid to the practical and social effects of this question. It was discussed only from theoretical, philosophical and scholastic points of view. But modern scholars give more heed to its practical and social aspects, and look at it from the angle of its effect on the way of thinking of the nations and their progress and decline. Some critics of Islam hold that the biggest cause of the decline of the Muslims is their faith in fate and destiny.
Now a question arises, if belief in destiny is a cause of the decline of an individual or a society, how is it that the early Muslims were not adversely affected by it. Did they not have a belief in destiny?