We already emphasized that emotions are associated to the lack of a short- range model, when a new external reality occurs. The word "angry" can be associated with the lack of a long-range model associated with a full section of the external reality (for instance when a person lives in an environment, which he/she doesn't fit in). In such a situation, the PSM is activated as well, but it has no solution. In fact, PSM can't build a long-range model. A long-range model is difficult to build, because it starts from a general model which is not directly associated to a specified external reality. The lack of a suitable long-range model means that many short-range models can become unstable, due to a lack of correlation between them. Such a person has a feeling that there is a problem, but he/she cannot identify it. Such a person is in an angry-status. About the same considerations can be associated to the word "anxiety". Here we can see a class of problems associated to the fact that the words in common life are not associated to the hardware and so, the external definitions are not precise enough. As the language will evolve based on internal definitions, the quality of the language will improve. MDT is able to generate a definition, and then a word has to be associated to that definition. Unfortunately, the words have already an external definition. Thus, there are two possibilities: to invent a new word, or to use an already existing word. In the latter situation, two definitions associated to the same word could exist: an internal one generated by MDT, and an external one, as we can find in dictionaries. My decision was to use as much as possible the already existing words, with the risk to have two different definitions associated to the same word. As MDT will be accepted, all the words associated to functions of the brain will be associated only to their internal definitions. 11: To be irritated, to be under stress Such a phrase is used when there is a temporary situation of instability of the structure of models. Such a status can affect the short-range models (to be irritated) or the long-range models (to be under stress). In the following, we will describe some situations when such a temporary instability can occur. 11a. There is a normal model associated to the actual external reality. The problem occurs when such external reality evolves in a cyclical way, for very long time. In such a situation, the prediction of the evolution of the external reality is identical with IR, forever. If the external reality is a sound, and if the sound contains a sequence which is repeated on and on, this uses a lot of energy of the brain for a nonsense activity (due to the hardware design, it is impossible not to hear a sound). Because the activation of other models becomes difficult, there will be an instability of the structure of models, and so there is an irritation-status.