Example: Let's analyze 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 quantity of data to be processed by an animal brain, and so, the brain becomes faster and more efficient.