In the psychology of motivation, balance theory is a theory of attitude change, proposed by Fritz Heider. It conceptualizes the cognitive consistency motive as a drive toward psychological balance. The consistency motive is the urge to maintain one's values and beliefs over time. Heider proposed that "sentiment" or liking relationships are balanced if the affect valence in a system multiplies out to a positive result. Structural balance theory in social network analysis is the extension proposed by Frank Harary and Dorwin Cartwright. It was the framework for the discussion at a Dartmouth College symposium in September 1975. P-O-X model For example: a Person () who likes () an Other () person will be balanced by the same valence attitude on behalf of the other. Symbolically, and results in psychological balance. This can be extended to things or objects () as well, thus introducing triadic relationships. If a person likes object but dislikes other person , what does feel upon learning that person created the object ? This is symbolized as such: Cognitive balance is achieved when there are three positive links or two negatives with one positive. Two positive links and one negative like the example above creates imbalance or cognitive dissonance. Multiplying the signs shows that the person will perceive imbalance (a negative multiplicative product) in this relationship, and will be motivated to correct the imbalance somehow. The Person can either: Decide that isn't so bad after all, Decide that isn't as great as originally thought, or Conclude that couldn't really have made . Any of these will result in psychological balance, thus resolving the dilemma and satisfying the drive. (Person could also avoid object and other person entirely, lessening the stress created by psychological imbalance.) To predict the outcome of a situation using Heider's balance theory, one must weigh the effects of all the potential results, and the one requiring the least amount of effort will be the likely outcome. Determining if the triad is balanced is simple math: ; Balanced. ; Balanced. ; Unbalanced. Examples Balance theory is useful in examining how celebrity endorsement affects consumers' attitudes toward products. If a person likes a celebrity and perceives (due to the endorsement) that said celebrity likes a product, said person will tend to like the product more, in order to achieve psychological balance. However, if the person already had a dislike for the product being endorsed by the