Table of Contents
One Word to Unite Them All
The goal is to develop a definition for 'system' that could used by the full range of “system” disciplines: Systems Science, Applied Systems Science and Systems Engineering across the major system types: natural, social and engineered.
Essentially a return to first principles which might open the playing field to a broader audience yielding a better answer.
I expect that a major (and likely correct) push back on this initial proposed definition is that it is too simple. Even if true, it can be used to agree that we are discussing a 'system', even across representative from the different system disciplines, and from there determine what is unique about THIS system, so we have a sub-class. As we work through these specializations, we will be forming the Taxonomy for systems which can form the base for a set of Ontologies and associated Schemas but with broader involvement.
Definition of a system
A system is a bounded interval of spacetime for which the inputs and modified outputs, consisting of matter and/or energy and/or information, can be observed and specified.
If we accept this definition, then:
- Since a system exchanges inputs and outputs with “something”, “something” can be labeled as another system
- Systems can either exist alongside a system in some environment or within other systems
Questions
1. Does this proposition provide a way to determine if “what we are observing” is a system?
2. Does this proposition capture everything we currently think is a system, up to the “Universe” (discussion about what is beyond 'space-time' to exchange with or 'wrapping around' and exchanging with itself is philosophy not science at this time) and down to “fundamental particles” (things not composed of smaller things)?
3. Do the proposition and theorems “feel” like they “makes sense”?
Discussion
I agree with this definition and use a similar one in my lectures.
As a physicist by education, I prefer using “4D volume of spacetime” instead of “interval”, as “interval” is commonly reserved to 1D volume of time.
I prefer using more general “inbound and outbound flows” instead of “inputs and outputs”.
I would consider abbreviating the definition to “system is all that happens in the 4D volume of spacetime” but this may be too much.
The “Not System” or “Environemnt” is an unbounded 4D volume of spacetime so it is not a systems per se.
@Sergey “Reply” doesn't appear to work so I am responding with another comment.
I am not a physicist and was looking for a term other than volume which implied 3D for me. Interval came up in a number of response to a search. 4D Volume seems correct and easy to parse, so it is a good update for the next proposed version which will generate once additional comments arrive. One goal of this activity is for the initial level of definitions to remain non-specialized enough to be accessible to all members of the 'systems' communities (Science and other Applied Sciences - a discussion topic is forthcoming on that) so we have shared talking points. That does not preclude using annotation to attach more domain specific language to let the specializations know they are being considered.
I am not clear about the unbounded 4D volume of spacetime as it appears to indicate everything EXCEPT for the system of interest which by this definition, provides input and accepts outputs from the SOI so MUST be a system.
A few comments:
Does a system have to give inputs and outputs? If so (to the best of our understanding) the universe is not a system.
Perhaps thinking of systems volumetrically is misleading–part of the fun of systems analysis is extricating systems that interweave. The company I work for is a system, when I work from my living room, is my living room part of the company?
Finally, should the distinction between matter/energy/information be made? Shannon information might be sufficient? Is information theory too arcane for systems engineers or do we just need to git gud?–I think information might be a good framework to hang the definition from
@Tom Yes, a system does interact with something. I agree that with our current understanding we cannot describe the boundaries of our universe so it does not meet this criteria (per my side comment in question 2 above).
From my view, the company question is one of association, aggregation, and composition. Is a company “a system” or “a System of Systems”. Are you the company? Only when you are on-site? Interesting philosophical questions that can lead to deeper understanding.
The following is a restatement of intent, NOT a comment on your comments. The goal for this specific page, is to imagine/uncover/create a description for “system” that can be used to determine if a 'thing' (=⇒ bounded 4D volume of spacetime) is a member of the system class that can be applied in the full range of “system” disciplines: Systems Science, Applied Systems Science and Systems Engineering across the major system types: natural, social and engineered. The reason for this endeavor is to find some common ground for discussion among these groups. Two of the important characteristics of the description will be: “NOT incorrect AND accessible”. More nuanced definitions will be able to build on this basic shared definition. We are trying to build something that is not SO unacceptable that it won't be used.