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System breakdown structure

Systems are simultaneously a whole for certain parts within them (subsystems) and parts for some encompassing whole system (suprasystems). Each subsystem is also a whole for its own sub-subsystems (relative to the initial system), and each suprasystem is part of a higher-level suprasystem. This way, we can talk about hierarchies of system decomposition into parts from top to bottom, or hierarchies of system composition from bottom to top. If we are not planning to further break down a particular system into parts, it is called an "element of the system", emphasizing that there is a whole system for which this subsystem is an element: "a part that cannot be further divided into parts".

Levels in hierarchical system decomposition (hierarchies/"graphs-trees" built in relation to composition/"part-whole"****) are called system levels. System levels are identified in the physical world **by observation; there is no need to "break down" the system to identify them! If you were to break down a living/functioning organism into functional organs, for example, it would be dead afterward! Therefore, system decomposition is performed solely by attention! There is no need to physically disassemble or reassemble anything! However, it is necessary to shift attention from larger parts to smaller ones and vice versa. It is necessary to ensure that the hierarchy for the "part-whole" relation does not include any other type of relation (such as a classification or specialization relation). Ensuring that you have not accidentally included a mental object in the physical breakdown of parts is also crucial.

A classic example of system decomposition is the division into system levels (from small to large) in biology: atoms-molecules-cells-organs-organisms-populations-biocenosis-biosphere. In addition to the term "system levels", biologists also use terms like "organization levels", "evolutionary levels", "levels of life complexity".

You can see that systems are depicted on the system hierarchy diagram by circles, and the arrow-diamonds traditionally represent the composition relation, where the whole is depicted on one side of the diamond, and the part is depicted on the arrow. In the diagram, it is shown that cells consist of molecules, but cells themselves are parts of organs. Organs consist of cells, but organs are parts of organisms.

The term "consist of" (composed by) does not mean that you can break down organs into cells and then reassemble these cells into organs. No, the term "consist of" refers to the fact that you highlight different organs in a functioning organism, identify cells within the organs; however, you can also trace back your attention to group cells into organs again, and organs into organisms. There is no need to physically dissect anything; system levels are used only for managing attention in situations with multiple objects that are made up of other objects and are themselves parts of other objects. System levels are determined by attention (which agents agree upon in their projects to coordinate their work); they are not "objective", meaning that different agents will suddenly discover them in various situations and different projects! On the other hand, systems: "objects of certain system levels" are not selected randomly; in the physical world, systems are usually stable, they are not easily affected by entropy, and they are not easily destroyed. Furthermore, system levels are often culturally conditioned, and this cultural conditioning is also supported by language. The knowledge that "a smartphone consists of a screen, a housing, a camera, a battery, and some electronic components" is already common cultural knowledge, there is no need to agree specifically on it today (unlike in the early days of creating the first smartphones). But specific decisions such as what belongs to the housing and what belongs to the screen (for example, the screen's protective glass - is it part of the screen or part of the housing?), what is included in the components of the camera (a chip that supports only the camera's operations - is it part of the camera or "some electronic components"? what about lens mounting rings on the housing - are they part of the camera or part of the housing?) - all of this will depend on the decisions of specific smartphone development and production teams, even today.

The hierarchy diagram does not show the system level of biocenosis or the ecosystem, then further, the biosphere (they are above the population level). There are studies showing that an increase in complexity levels is inevitable, meaning the unity of parts into increasingly more complex wholes on many system levels[1].

The levels of atoms and elementary particles (lower than the level of molecules) are not shown in the diagram, but that does not mean they do not exist: the principle of the open-world assumption, "what is not mentioned in our text is simply not said, but that does not mean it does not exist," should be applied. This is how you should read the system diagrams: any top level in them is not the highest (you can always find some higher suprasystem, ultimately all systems are part of the universe or, in some physical theories, part of the multiverse as an infinite set of universes). Molecules are shown in this diagram as elements (indivisible subsystems) of cells, but cells are also subsystems, their indivisibility is conditional, it is simply not considered in the activities for which this diagram was created. Therefore, even at the bottom of the system hierarchy, you can always find some parts like "elements." This small range of sizes of physical objects is crucial for human activity and is roughly proportional to the size of humans themselves. These systems, which are neither too large nor too small in astronomical or microcosmic terms, serve as the subject of activity—most often ranging from several kilometers (e.g., construction projects: skyscrapers, dams, and bridges) to several nanometers (transistors on computer chips). It is at this small range of sizes that humans typically interact (with their tools! Not necessarily with their hands!). In cosmophysics and microcosm physics, there is much more beyond these sizes, but humans prefer to operate within this range without venturing beyond it, changing the world within these limits without exceeding them.

Explicitly specifying the system level is crucial for managing attention. Formally, when touching a flower on a plant (the "organs" level in the system decomposition of plants), I am also touching the Universe (since the flower is part of the Universe!) and touching elementary particles (are definitely present in the flower!). Or, I am touching the entire plant and touching the cell level. It is unclear what I have touched, what is the subject of my attention! Therefore, it is necessary to explicitly identify the system "object of attention" that somehow allows me to determine the scale of "touching." In our example, this would be the "flower."

When waving my hand, I am waving with all the molecules of my hand - but it would be incorrect to talk about molecules when discussing waving one's hand. Also, it would be incorrect to "wave with the body" (since the body is too large of an object). Therefore, "waving my hand" means moving a system located many system levels above the molecular level but still below the level of the entire body.

System levels are essential; they reflect the essence of the system approach—new properties emerge at each system level due to emergence/system effect, hence discussions are usually conducted separately for different system levels by agents who deal with the properties displayed by systems at that system level, as well as the properties of the super-systems resulting from the properties of the current system level. Roughly speaking, microbiologists discuss cells, physicians discuss the human body as a whole, and managers discuss collectives of people. Detailed discussions at each system level significantly simplify discussions of complex systems. If you are discussing an enterprise, you talk about people, equipment, material resources, buildings, and structures, but you usually do not need to discuss the planetary system around the Sun, of which the enterprise is a part, like a part of the Earth, or the biochemistry of cells in humans, as part of the biochemistry of the enterprise.

Remember that if you are discussing a problem at too low of a system level, it is a reductionism error, and if you are discussing a problem at too high of a system level, it is a holism error. Maintaining discussions at three levels is correct:

  • The suprasystem with its environment and its properties. For example, a computer as a whole and its characteristics (dimensions, weight, power consumption, performance according to recognized tests)
  • The system-of-interest as a whole and other systems at the same system level within the suprasystem. How the collective work of systems at this level affects the state and properties of the suprasystem. For example, the central processor as the system-of-interest, memory, motherboard, power supply, cooling, the casing.
  • The subsystems of the system-of-interest: how their collective work (interaction) influences the states and properties of the system-of-interest. For example, for the central processor - the cores with arithmetic-logic devices, multilevel cache memory, input-output blocks. And immediately, here is your attention test: if you imagine a "real" (and not from diagrams in a book) central processor, you will see a chip embedded in plastic (or even several "chiplets") with connections, with some zones on the chip containing the cores with arithmetic-logic devices, multilevel cache memory, input-output blocks. And now, where is the real processor? The attention to detail is crucial; if a real central processor does not exist, then interest will go elsewhere, such as to a logbook or a plant.

In accordance with our systemic approach, we require the system decomposition to be entirely physical/material: each system level is identified in terms of a part-whole relation between physical objects, i.e., objects occupying positions/spaces in space-time. It is important for students to remember this: if their system decomposition includes non-material parts, then in systemic thinking this is like 2*2=5, and for this mistake, they immediately lose two points and are sent for a retake. We cannot recommend that adults be fired from work for this, but we are very close to providing such advice.

Attention should be sufficient to monitor the physical nature of the part-whole relations at multiple levels up and down. If there is not enough attention for this monitoring (given that this attention is supported by records - there is no need to keep everything in mind!), then something should be done about it, for example, retake the course "Modeling and coherence" (honestly, by completing the assignments). Working with absent attention is dangerous, mindlessly drifting into a non-physical world or confusing what is a part and what is a whole - this is dangerous for the project.

The multi-level decomposition of systems is essential: at the top level of any such decomposition, there will potentially be the universe, and at the lowest level - superstrings, but these extremes are of less interest to people, therefore system decomposition is done for a range of sizes of physical objects. For human activity, a very small range is crucial, roughly equivalent in size to humans themselves. These not too large and not too small systems in cosmic and micro-world scales are the focus of human activity, often interacting with these objects at different system levels. In cosmophysics and microworld physics, many fascinating things exist beyond these scales, yet for now, people prefer to alter the world within these limits, not exceeding them.

Explicitly indicating the system level is crucial for managing attention. Formally, by touching a flower on a plant (the "organs" level in the system decomposition of plant organisms), you also touch the Universe (since the flower is part of the Universe!), and you also touch elementary particles (which are definitely present in the flower!). That is why it is necessary to explicitly identify the system "object of attention" that allows you to determine the scale of "touch".

When waving a hand, the action involves all molecules of the hand - but it would be incorrect to describe this action in terms of molecules. Also, saying "waving with the body" would be inappropriate (as the body is too large of an object). Thus, we should describe the action as "waving with a hand," referring to the system located many system levels above the molecular level but below the level of the entire human body.

System levels are crucial, reflecting the essence of the system approach - new properties emerge at each system level due to emergence/system effect. Therefore, discussions are typically conducted separately for various system levels by agents who deal with the properties displayed by systems at that system level, as well as the properties of the super-systems resulting from the properties of the current system level. For instance, microbiologists discuss cells, medical professionals talk about the human body as a whole, and business managers discuss groups of people. Detailed discussions at each system level greatly simplify the discussion of complex systems. If you are discussing an enterprise, you would typically talk about people, equipment, material resources, buildings, and structures, without necessarily discussing the planetary system around the Sun, to which the enterprise is a part, or the biochemistry of cells in humans, as part of the biochemistry of the enterprise.

Remember that discussing a problem at too low of a system level is a reductionism error, while discussing a problem at too high of a system level is a holism error. The key is to maintain discussions at three levels:

  1. The suprasystem with its environment and its properties. For example, a computer as a whole and its characteristics (dimensions, weight, power consumption, performance according to recognized tests).
  2. The system-of-interest as a whole along with other systems at the same system level within the suprasystem. Understanding how the collective work of systems at this level affects the state and properties of the suprasystem. For example, the central processor as the system-of-interest, memory, motherboard, power supply, cooling, the casing.

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