Example: there is a book of a researcher named Titu I. Bajenescu with the title "The performance of the artificial intelligence" (Albastra Publishing House, Sibiu, Romania, in Romanian language). In the Bibliography of this book, the author has many hundreds titles, including 241 of his own. There is, in the book, a dictionary of the main terms used by author. One of these terms is "intelligence". The author defines it by 16 different statements which contains at least 12 undefined words (to know, to understand, rational, conceptual knowledge, sensation, intuition, to discover, spirit, to addapt, character, to learn, problem, experience...). Thus, to understand what is "intelligence" we need to know in advance the definitions associated with all of these terms. These defintitions must contain only words which are already defined.... An endless proces starts in this way. Of course, the author has no definition of the term "intelligence"; he has only a description of it. Even worse, based of the impressive bibliography, it is clear that this very important term has no definition. The authot himself recognize this by saying: "the intelligence is a hard to define concept because it is impossible to find a single definition to be accepted by all". In association with the above example, MDT-model generates the normal definition of the term "intelligence" as the facility to make and opperate a long range model. The book cited above cannot be used and the situation is the same with all the books associated with the function of the brain, available now. I used only brute data associated with the history of the human species (e.g. dictionaries or press reports) which cannot be cited in a specific way. Dorin Teodor MOISA moisa@zappmobile.ro October 2004