From this we can see the naivete and ridicule of the present so-called intelligence tests. These tests are ridiculous, because there is no fundamental theory, which could at least define and correlate the used terms. My theory says that there are facilities associated to image and to symbolic models (there are arts and sciences, watches are analog or digital, on computer screens we have icons and text etc.) We also have facilities associated with obtaining information from the external reality and facilities associated with modifying the external reality. A minimum observation of the external reality suggests four independent groups of IQ tests: action/knowledge on image/symbolic models. As this is not the case, the present IQ tests are naive and ridiculous, not only from the point of view of MDT. In the following we will give a structure of fundamental IQ tests based on MDT: 1. The capacity to build M image models 2. The capacity to build YM image models (concept models) 3. The capacity to assimilate image YM 4. The capacity to build symbolic YM 5. The capacity to assimilate symbolic YM 6. The capacity to assimilate image ZM 7. The capacity to build image ZM 8. The capacity to assimilate symbolic ZM 9. The capacity to build symbolic ZM 10. The capacity to assimilate symbolic ZAM 11. The capacity to build symbolic ZAM 12. The capacity to assimilate image ZAM 13. The capacity to build image ZAM 14. The capacity to activate symbolic ZAM 15. The capacity to activate image ZAM 16. The capacity to build image AZM 17. The capacity to activate image AZM Example: For a person who has to be a public relations representative for a business, the qualities which will count, on first place, are the capacity to assimilate symbolic and/or image models and to act based on them. He has to have a reduced tendency to build own models, in order to be fit to the requirements of the position. A person who will work in scientific research has to have capabilities to create new symbolic models. Among these capabilities, interdependence should exist. We can suppose that persons who have the tendency to build models will have difficulties to assimilate external models. Their tendency will be to modify any external model in a personal manner. At the same time a person with capabilities of assimilation of external models, will have diffculties in building own new models, and will not try to modify the assimilated models, even if they are not suitable to the external reality anymore. Other parameters associated to the brain are connected with the stability of these capabilities, on long/ short term, and in normal or extreme conditions. These parameters will charactrize the reliability of these capabilities in special conditions.