Our personalities are the products of many factors and conditions which we have inherited or which exist in our environment. No two persons, except identical twins, have the same heredity. No two persons react in the same way to their environments. Every personality is unique and makes the individual different from others.
Some people believe that heredity is the most important factor that decides what any person will be like. Other people believe that the environment is the most important influence in deciding the behavior of any person. For ages these two viewpoints have been expressed and the question as to which is more important has been discussed. Today scientists agree that the best approach to the problem of explaining behavior is a study of the combination of the two influences - heredity and environment.