# Distinctiveness of Parts (in Combination with Functionality and Purposefulness)

This property is associated with the external boundary separating the system from the environment, or the boundaries between the heterogeneous sections within the system. To the discussion (in Section 2.1, Part I) about the difficulties of constructing a composition model, it is worth adding a more detailed discussion of the very concept of the boundary of a certain entity.

Whichever entity we consider, we describe it by listing a set of its properties, observed or presupposed characteristics, and attributes (measurable parameters recorded in the appropriate qualitative or quantitative measurement scales). The state of a particular entity (the entire set of its elements) is characterized by a certain set of values of these parameters. If we think of each feature as a coordinate of some space, we get the state space (phase space) of the entity, in which its static (instantaneous) state is represented by the corresponding point and the dynamic one (time process) by a certain trajectory.

A boundary is a surface in phase space that divides the space into two regions. Although such a partition can be carried out as you like, when it comes to determining the boundary of a system, the partition must meet the appropriate conditions: the limited subspace of the system states contains many different (differing in coordinates) elements but have at least one feature common to all elements of the system, which is not inherent to elements not included in it. This specific indication is called a classifier. For example, the condition of each patient is characterized by their own set of values of signs (gender, age, weight, height, temperature, blood pressure, blood composition, etc.), but there is a classification feature that allows you to divide the space of states into two areas: one includes patients with a disease, the other includes healthy (or sick with other diseases) people.

Finding boundaries between areas corresponding to different diseases is the goal of every doctor for diagnostic purposes. Often the main distinguishing feature of the system is its possession of some specific function. When the output process of the system is considered as its objective function, the definition of the boundaries of the system is facilitated: it includes everything involved in the implementation of this objective goal. This makes it possible to clearly distinguish between the nervous, circulatory, and digestive systems in the body; or the heating, electricity, and sewage systems in the building; or the healthcare, education, and public security systems in the state; etc.

Another reason for separating the system from its environment can be the fact that often the connections between parts of the system are much stronger than their connections with the elements of the environment, or they sharply differ qualitatively. For such systems, the boundary appears to be a natural partition between them and the environment. A striking example is the external framing of physical bodies — the surface of various objects, technical structures, organs in the body of animals, planetary systems, settlements in the territory, islands in the ocean, etc. In such cases, consider the natural boundaries of the system. Apparently, this is what the Father of Cybernetics N. Wiener had in mind when he spoke about information links in social systems: “The system extends to the limits to which information reaches”.

However, (by virtue of the law of universal relationship in nature!) even natural boundaries sometimes have to be described roughly. For example, the atmosphere of a planet with a height is thinning very gradually, and its outer “boundary” can be carried out only conditionally. Moreover, the presence of a subjective factor in the relationship between reality and the subject makes the distinction relative, conditional, and subjective. Different subjective goals of interaction with this system force us to “cut out” the contour from the objective goals of the intertwining of all and with all.

For example, the boundaries of a university look different when viewed for different purposes. In the land cadaster of the city for the University is assigned a certain territory. In labor law, the belonging of the employee to the university is defined situ- ationally (remember the example with the payment of sick-list in Section 2.1, Part I). With distant learning, students of the university may be located in remote regions.

Another example is the river. Geographical maps of the world only display the riverbed. A geophysical approach to the definition of the river system includes all tributaries and catchment areas, extending the concept to the river basin. Environmentalists consider the boundary of the river system as its watershed with the basin of another river. From the positions of the river fleet, river boundaries narrow from the banks to the limits of the fairway, designated by special signs (buoys).

Another example is man. In society, external border of humans is “judged by their clothes”. The visible natural outer border is the skin. Doctors consider the outer boundary of the body as the shell of the gastrointestinal tract, relating its contents to the external environment. Some researchers of the phenomenon of man have established the presence of a special field surrounding the human body (the Kirlianu effect, biofield, aura), which is its integral component.

Hence, the main factor in carrying out the boundaries of the system and its parts is the subjective goal of building a model of the system’s composition. This led to one of the definitions of the system as a set of interacting parts: the system is all that we want to consider as a system. The objective basis for such a statement is the universal relationship and interdependence in nature, that is, the integrity of nature: nature itself is a single whole system of systems.