As we know, the basic function of any brain (human or animal) is to make and operate image-models. Let's continue with the basic differences between the human and animal brain.

THE HUMAN BRAIN (Introduction)

The basic difference between the animal brain and human brain is the capacity of the human brain to make and operate symbolic models. The animals are not able in any way or form to make and operate symbolic models.

We already a.n.a.lyzed how a human or animal brain interacts with an image to make an image-model. For the symbolic models the interaction is different.

A symbolic model, as we know, uses as elements letters, words or numbers. When a human brain interacts with such elements, the M-models will contain such elements as specialized YM-models. Such YM-models contain all the shapes of the letters, for instance. It is not necessary to discover the elements, because they are there in an explicit way.

All the symbolic elements are contained in a symbolic model called General Communication Language (GCL). There is a spoken language and a written language, as directly interacting symbolic models. This is true only for cultural zones which use alphabets. There is a specific application which treats this problem.

For a given written text, we have all the elements and all the relations between the elements, in an explicit way, as words. Usually, the elements are the nouns and the relations between them are the verbs. Any sentence is a symbolic model, for instance.

Example: the sentence: "I go home" has two elements "I" and "home" and a relation between the elements as "go".

The stability of the symbolic models is based on logic. When a symbolic model is stable we call it a logical model. A logical (stable) model can be understood by anybody who can make and operate symbolic models.

Sometimes there is a correspondence between image-models and symbolic-models as in the following example.

Example: Let's a.n.a.lyze the sentence "An apple falls from an apple-tree". We have two elements and a relation between them. On the other hand, we can make an image-model that describes the same situation: an apple falls from an apple-tree.

So, the logic could have been born in the process of translation from an image model to a symbolic model (when the translation is possible). As an image- model is stable based on laws of harmony, a symbolic model is stable based on the laws of logic.

Here we have in an implicit way the definitions of harmony and logic, as the rules and methods to ensure the stability of an image-model (harmony) or a symbolic-model (logic). An implicit definition means that we are able to recognize the effect of harmony or logic in a structure of data.

THE HUMAN BRAIN VERSUS ANIMAL BRAIN

MDT is a theory that treats the human and animal brain in the same framework.

I present here a possible evolution of the brain, from animal brain to human brain. It is very important to specify that the theory is like a tool: it does not support and also does not reject the evolutionist theory. MDT just describes the situation.

For any external reality, the brain (human or animal) will make an image- model. This function is basically the same for human and animal brain.

In a given external reality many similar elements could exist. For any element, the brain has to make a YM-model.

For instance, a dog has to make a YM for any dog which it meets. Such a big number of models use a lot of the brain resources.

When there are many similar elements, a solution is to make a concept-YM. Such a YM will fit a big number of similar elements. This reduces the quant.i.ty of data to be processed by an animal brain, and so, the brain becomes faster and more efficient.

Thus, the first level of evolution of the brain (level 1) is the extensive use of the concept models. This level is, probably, reached by all animals.

Observation: the human and animal beings continue to use, for some special situations, pure image models. A pure image model is a YM-model a.s.sociated with a single ent.i.ty of the external reality. For instance, a cub has a pure image model of its mother.

The first step of the evolution of the brain is based on concept models. A concept model fits an entire cla.s.s of ent.i.ties of the external reality. During the interaction, the brain will use a concept model and then, in M-ZM, new properties will be added, or even new elements, if necessary, to understand better and better the external reality.

The evolution of the brain continues with level 2. This new facility is based on label-models. As we know, faced with a given external reality, the brain makes an M-ZM model that is able to predict the evolution of the present external reality. Such models are called local-M-ZM. On level 2, it is possible to make a new type of models, which are called label-models. A label- model is able to activate a ZM-model, from the available models of the brain, regardless of the local-M-ZM.

Example: an animal senses a specific smell. This can be a.s.sociated with food or with danger, for instance. In such a situation, the animal can activate a specific ZM-model, which has no direct connection with the local-M-ZM model. This is level 2 of the evolution of the brain.

At this level, a special kind of communication between animals occurs. This kind of communication based on label-models is used by human beings as well. It is not precise enough and is also very limited, but useful in many situations, and very fast too.

The level 2 is the highest level achieved by the animal brain. The evolution of the brain continues with level 3.

We already saw that, at level 2, a label-type model activates a ZM model. The next step is to activate not the whole model, but only some a.s.sociated truth of the ZM-model. In this way, the brain has to manage a reduced quant.i.ty of information and so becomes more efficient.

This is a critical point, because it is the barrier to separate the animal world of human world.

Thus, there is a ZM-model and an a.s.sociated label-model. The problem is to a.s.sociate to the label-model only some truths generated by the a.s.sociated ZM- model. A ZM-model is an image model, and so its truths are also of image-type. The problem is to record such truths in a different way, based on a totally new function.

MDT cannot indicate how exactly this facility works. The theory is not concerned with the technological implementation of the functions. The theory just says that some truths generated by a ZM-model have to be recorded in a different way. In this way, the label-models become words, and the a.s.sociated truths become symbolic definitions of the words.

On level 3 a label-type model can activate an a.s.sociated ZM model, but it can activate only a collection of truths as well, which are different from the 'ordinary' image-truths of the ZM.

It is possible that the General Communication Language (GCL) appeared based on this facility. The presence of a GCL in a brain will characterize that brain as a human brain.

Example: when the word "dog" is heard, it is very probable that we activate at least one suitable ZM. But when we use the sentence "I go to the forest with a gun and a dog", it is very probable that we do not activate any ZM-model. The sentence is understood based on symbolic models and based on logic and so we do not need any image-model. In this way, the quant.i.ty of information that has to be processed by the brain is reduced very much. The image models will be used only when we have to make a precise model of the action.

The human brain continues to evolve with level 4. On this level we have words and a.s.sociated symbolic definitions, but no ZM-image-model.

Example: Let's take the following words: "this apple", "apple", "fruit", "food". "This apple" is a.s.sociated with a pure image model. "Apple" is a concept type image model. "Fruit" and "food" cannot be a.s.sociated with any image model (we cannot imagine what is fruit or what is food).

So, on level 4, the human brain can make and operate symbolic models without any connection with image-models.

On this level it is possible to develop logical and mathematical languages and, in this way, to make positive sciences a.s.sociated to the external reality.

Example: Newton's Mechanics is a symbolic model a.s.sociated with the physical bodies. The basic terms of this symbolic model are ma.s.s, s.p.a.ce and time. None of these terms can be a.s.sociated with image models.

The evolution of the brain continues with level 4+, but I prefer to call it level 5 (up to now it is the highest). This level was attained only 100 years ago. On this level the symbolic models break totally with image models.

Example: Newton's Mechanics describes the movements of physical bodies. But we can imagine such movements. Here Newton's symbolic model can be translated also in image models.

The pure symbolic models cannot be translated in any image models. The only symbolic model of this type is Quantum Mechanics.

Example: in a.s.sociation with Quantum Mechanics there is a "cla.s.sical" problem called "the dual nature of light". There are some experiments, which prove that light is a wave. But there are also some other experiments, which prove that light is made of particles. It seems that we have big logical problems here. The aberration with "the dual nature of light" is supported also by some great physicists (R. Feynman, for instance).

Physicists in Quantum Mechanics already solved the problem of the nature of the light. The "dual nature of light" is not a problem of Physics, but a problem of thinking.

The problem occurs when the physicists try to explain to us what happens. At that moment, they use terms as "wave" or "particle" which are a.s.sociated with image models. The same terms, in Quantum Mechanics, are a.s.sociated with mathematical formulae. There is no connection between the world of Quantum Mechanics and the world of image models. If someone forces such a connection, then some big logical problems can occur.

As MDT says, any information is non-sense without declaring the model that generated that information. In the above example, the nature of light is well understood by physicists in the symbolic model called Quantum Mechanics. If we don't know Quantum Mechanics, then it is not possible to understand the answer. So, if we do not know Quantum Mechanics, then it is forbidden to ask any question a.s.sociated with that field.

Let's evaluate the world based on these levels. There is a fraction of the population who is staying on level 2, and just occasionally goes on level 3. The majority of the population is on level 3, and occasionally goes on level 4. There is a small fraction, which is on level 4, and occasionally on level 5. This fraction produces scientific and technological advance.

To understand the MDT theory, at least level 4 is necessary.

HUMAN BRAIN: EVOLUTION OR EXTERNAL INTERVENTION

Some activities of the human and animal beings are similar. So, there is an idea that evolution from animal brain to human brain could be possible.