Like the development of attitude and behavior, the change in these characteristics is also highly influenced by society. The basic rule governing attitude change is the Principal of Consistency.
People expect all things in their mind to agree with each other. They expect that all good things should assemble together against all the bad things, which should also assemble together (Brown, 551). When two items in your mind disagree, dissonance occurs. The mind does not want to be in a state of dissonance, so something must happen to resolve this.
Other resolutions can occur if you figure out an explanation of why your opinions differ. For example, you may decide that you friend was not in a good mood when he or she watched the movie, and did not enjoy it as much as he or she could have. Another reason might be that if he or she watched it in a theater, the seating may have been poor. These reasons differentiate between the two situations, and the two viewings of the movie are no longer the same item, so the dissonance is resolved. This can also happen with a live performance if you and your friend saw two different showings, and the acting and other factors in one were better than the other. The dissonance will only be resolved if you truly believe in these reasons.
Since attitude and behavior are not the same thing, a person may offer a reason even if he or she does not believe it. This might be done so others will think that all is well and he or she would not have to show the dissonance in their outer behavior. However, the dissonance is still present and his or her attitude must change in a different way in order to remove this dissonance. This may take the form of a simple resolution, and the person's opinion of the other person may change, even though he or she does not show it in their behavior.
These are simplistic examples. In actual fact, attitudes and opinions do not change as easily as this, and change in different magnitudes, depending on the strength of the bonds between items. For example, if you and your friend had known each other for a long time, chances are that there is a very strong positive bond between you, and it would not change as much as the bond between you and the movie. Or perhaps the bond between you and your friend would change in a different way. Then you would still like your friend, but your perception of him or her may change. You can read a document on cognitive consistency to learn more, or for a more detailed explanation of the three major consistency theories, read Cognitive Consistency Models.
Dissonance can also occur between a person's attitude and behavior. If a person acts in a way that does not agree with his or her attitude, then an attempt will be made to regain balance. This means that he or she will either correct the behavior and try to make amends, or change his or her attitude and come to accept that type of behavior. He or she may also attempt to excuse their behavior and blame it on a temporary lapse brought about by a situation that required him or her to act out in such a way for a greater good or lesser evil.