We saw the concatenation yesterday and we see the mental process of today, the concatenation is associated with a direction in the mathematical sense. Now, we function as a segment of the same time, at the same time as the infinite of a point of the world and at the same time as the end of the segments at another level of abstraction. Its segments are symbolically linked in places. Its permanent places on the segmentation of it allow to circulate chips. Tokens represent the type of thoughts that happen in the brain. Tokens move from one place to another, from the state of things to the state of things. The tokens represent in the state or in each place, which is the same thing in symbolism, the passage from one state to another of the abstract facts, one also says of the represented facts. Or in other words, the passage from a static and coherent level, for a given set of laws, to a meta together, when modifying or adding an additional law. Petri nets MOP from the beginning of the world. it also allows you to analyze with different levels of abstraction and so time .