He always seems to be in the right place at the right time, and this may help him in adapting to situations. He does not expect anything bad to happen, and so it usually does not. In addition, because Forrest is so simple, he does not create barriers for himself, and so, he becomes more adaptable and flexible as a result. "You never know what you're going to get" is OK with him, and even if he gets the "bad" chocolate in the bunch, it will be OK, because he is adaptable and flexible. Forrest could not be anything else and be such a simple character. Complexity brings worry, inflexibility, and a whole host of other human qualities that Forrest does not possess, simply because of his simple, trusting nature, and the lessons he has learned in life. His behavior, which is very important, also seems extremely normal to him. He sees other people with problems and worries, and he simply does not comprehend all the stress in their lives. When he has a problem or a question, he runs (across the country and becomes a folk hero). Certainly, this would be considered abnormal behavior, and yet, for Forrest it is completely natural and normal. He is such a complex character in such a simple shell that his actions always fit him, no matter how outlandish they might seem. He is perfect as the unusual and yet always endearing simple man and his behavior all goes back to this simplicity and innocence that are the roots of his personality. His behavior might not be normal for others, but it is normal for him, and that is another thing that makes his character so appealing and genuine. He does not care what others think about him, and his behavior is all geared to his own wants and desires, rather than bowing to social or other pressures. Finally, his social and moral development really do not alter throughout the film, although he does become dimly aware of social causes like the fight for Civil Rights and the protests against the war in Vietnam....

His moral development does not alter because he remains innocent and trusting throughout the film, and has always had a high set of morals and principles instilled in him by his mother. She may sleep with the principal to get Forrest admitted to regular school, but she does have morals that she hands off to Forrest and always expects him to maintain. Forrest is probably one of the most principled characters in film, simply because of his innocent and trust of others. Happily, this does not come back to harm him very often, and he manages to uphold his beliefs no matter what happens to him. Even when he becomes wealthy, it does not change him, it just makes his life a little easier.
Socially, Forrest will never exactly fit in. Those close to him love him for his innocence and trust, but in the larger social sense, he will always be somewhat of a loveable social misfit. He simply does not understand the social structure and mores of most of society, which places so much value on things that do not seem important to him, like fashionable clothing, large houses and cars, and all the other trappings of society that are so important to so many people. He just does not need those things to be happy, and never will. It is not part of his personality, and it is clear it never will be, no matter how much money he makes.

In conclusion, Forrest Gump is a deceivingly complex character in a very simple shell. Psychologically, he is simple-minded and has a low IQ, and yet, he seems more compassionate, caring, and innocent than just about any other adult could ever be. He is wise in his innocence, and it makes him endearing and successful at the same time. He is also very complex in his own way. He does not allow society or others to influence him; he makes his own decisions and choices. He is a model for others, and a character that is rich in detail and complex in his own way.

References

Finerman, W. (Producer), & Zemeckis, R. (Director). (1994). Forrest Gump. [Motion picture]. USA: Paramount Pictures.