Principle of the Postman ​

Addresses are usually compiled so that different levels of addressing allow to clearly find an object, the object is unique within some level of addressing, it is easy to find — this is the mailman principle (suggested by A. Nechiporenko during one of our seminars). For example, the address of a plastic overlay on the leg of a table essentially lists objects in a system breakdown, allowing to switch from focusing on the entire Universe to focusing on this plastic overlay: Universe, complex of superclusters of the Virgo Supercluster, Milky Way, Orion Arm, Solar System, planet Earth, Russia, Rostov-on-Don, Bolshaya Sadovaya street, house 105, classroom 323, first desk from the board by the window, left leg of the table, plastic overlay. The address "Universe, Solar System, House 105, plastic overlay" is an incorrect address of the target system, an incorrect reference to the target system.

In the system breakdown, the supra system should be determined as close as possible in terms of the "part-whole" relationships from the target system, to be in the immediate environment. There can be many different types of errors:

• Skipping levels. The system level that is too far from the target system is usually declared, for example, instead of the target system, its supra system is named, or even a system several system levels above the supra system. A typical example: I am making a car! Which is followed by a long story about frost-resistant batteries. Why? "Well, I am interested in frost-resistant batteries, they are used in cars." "Can they be used, for example, for screwdrivers?" "Yes, perfectly." "And if the screwdrivers are in Yakutia?" Yes, this is much better than a car, it's a great market for my frost-resistant batteries! I am working on screwdrivers! (after some questions, it becomes clear that the battery is also not of interest, the focus is on the frost-resistant electrolyte — that will be the target system! The project deals with frost-resistant electrolyte).
• Overgeneralization. This is kind of a violation of addressing, but it is not a part-whole relationship, but a level of generalization/specialization in the classifier. For example, not "single-seat training aircraft", and not even just "aircraft", but "flying machine". What are you creating? A flying machine! And in reality, it's a toy airplane with a rubber motor. So, name it according to its role "to be a toy": "toy airplane". Will "flying machine" be correct? For a mathematician — yes! But we are not dealing with mathematics here, we are talking about systems thinking. We need all names and reflections for activities, not for "logical correctness". To understand what can be done with the system being created, the name "toy airplane" is much better than "flying machine".
• Not specifying the whole system, or a neighboring system (in the environment or even among the creating systems), hoping that the target system will be identified by the interlocutor independently, by inference. Essentially, this is about metonymy.^[1] — one physical object (or class of such objects) is replaced by another (or its class) that is in some relation to the object. And instead of the name/indication of one system, suddenly the name of this other system appears. This connection can be both "part-whole" and any other. "I ate three plates" — not the plates, but the food on the plate. "The bucket spilled" — not the bucket, but the water in the bucket. In the case of metonymy, the target system can be called anything that is in some relation to the target system: everything that falls within the sphere of attention. Metonymy should be checked, tracking that there is specifically talk about relationships of "part-whole" and taking into account the time of consideration (operation or creation), and then specify further which system in the final system breakdown is the target, at which system level we are working with it, what language we speak about it.