E.g. the members of the Communist parties are forced to accept that the "working class" is the leader of the society. This model is not in PSM (the person has no illness) but, they are forced to use this model. This externally-imposed model determines that any data from external reality should be compatible with the externally-imposed model. Their structure of models evolves in a paranoiac-type structure (it is not possible to discuss freely with such persons). A "soft" form of XIP occurs in people that are representatives of a state institution. For the XP paranoiac persons (there is an OMPSM), the external data could collide with the OMPSM. The solution for them is to distort any external information to be compatible with their OMPSM. But, in a complex structure of external realities, this method cannot work (it is not possible anymore to build a harmonic/logic structure of models by distorsion). The only solution is to fragment the data. This means that the same facts from external reality have a different interpretation depending on the environment. This is XPSC. Conclusion: a paranoiac structure of models evolves to schizophrenia too, as the external reality is more and more complex. ETA 21: Disharmonies of the functions of the brain We know from the general theory that two basic modes of interactions between humans and external reality exist. The first consists in obtaining better and better models of the external reality (ZM). The second is modifying external reality based on action models (ZAM). Disharmonies are associated with the importance given to each facility. Thus, there are two categories of humans: more knowledge or more action oriented. Without action on the external reality, knowledge is limited. On the other hand, people with a reduced knowledge of the external reality can't build good quality models, and so the capacity of action on the external reality is limited or inefficient. Disharmonies are thus determined by the following factors: - the capacity to build models of the external reality - the capacity to build action models - the capacity to activate action models. All these three factors are in a very close interdependency, whatever the interaction between the brain and external reality might be. A disharmony cannot be associated with a psychical or a pathological status. The disharmonies contribute to what we call personality. In this chapter, we will talk about people who have no disharmonies. The perfect situation is the case of those who build action models compatible with the models of the external reality. These people are those who do not intend to do more than they are able to. Such people will succeed in all they want to do. They are happy people. However the happy people have little contribution to the progress of society, even if they contribute significantly to its stability.