Questions About Systems and Their Components

[BillTre]

I have a terminological question: should system parts defined by functional interactions or by being inside (and including) the system’s physical boundary?



System components are often defined as part of a system based upon their interactions that lead to the system’s success in achieving its (often human defined) goal(s).



This sets-up a situation where functional system parts could be interspersed among non-parts, that are not functionally involved with the system, in the same region.

A biological example of this would be the circulatory system which is intimately interspersed among the non-circulatory parts of the tissues it services.



Alternatively,

• components of a naturally forming system (like a cell precursor) might be defined as all those chemicals in and contained by the “cell membrane”. When such a natural system is initially set-up, a group of potential components (chemicals) would be collected within the system’s physical boundary (lipid membrane assembled from chemicals produced by some geochemical process).
  
  However, this could be just considered the set of chemicals contained by or composing the membrane from which a system and therefore its components might later be derived.
• Initially, a new potential system would likely include chemical parts that do not contribute to the system’s success (in being autopoietic (able to make its necessary replacement parts)).
• Possible components could be:
  • detrimental to system functioning
  • without meaningful function to system functioning.
  • parasitic to system functioning
  • pathogenic to system functioning
• These not positively functional parts could alternatively be considered non-parts. That might become functional parts at a later time.

Today’s naturally evolved systems (living systems) have had their efficiency honed for about 3.8 billion years, such that they are now highly efficient and could be almost entirely composed of functionally important parts (molecules and chemicals). (One could argue that water molecules and hydrogen ions (protons) are functioning parts of a cellular system in that they are involved in reactions, metabolism, and osmolarity.)

 

[DaveE]

Sorry, you're going to have to be much more specific about your area of interest here. Computer science has systems, but not too much interest in physical boundaries. This question is way to general to answer IMO.

OTOH, I'm at a loss to describe any "system" that doesn't have function(s) included in its definition.

Also, lines, sometimes a bit arbitrary, have to be drawn. You could argue in the extreme that the entire universe is a single quantum wave function with everything interrelated somehow. You get to define the system as you please. You will never, ever, be 100% correct. There's always an outside influence at some level. Definition of a simplified model of the real world is the bedrock of science. We all do it, all the time.

 

[BillTre]

Thanks for your response @DaveE.
We seem to agree on some of the basics:

1. Systems have functions (often) as part of their definition (which are often also involved in identifying their parts).
2. For many systems, boundaries are not that important.

I will try to make things more clear (sorry its so long).

All of these systems I am talking about are chemical systems. Systems made of interacting chemical parts.

My issue is ultimately with how living systems arise. (There are many theories which I will not go into here.)
Modern living systems (AKA living things) are made of groups of chemicals that interact to achieve goals that are the result of selection processes. The selection processes result in things that persist lasting longer over time.
The details of how this is done results in natural systems that have the properties favoring persistence.
Persistence can be increased by:

1. Robust physical persistence over periods of time (tough like a rock).
2. Systems that can persist because they are able to make replacement parts for those that go bad. This lets the system persist longer than the life time of its component parts. This is an autopoietic system.
3. Systems that can that make enough parts to have extra in excess of its replacement needs, resulting in growth. If growth then leads to division (which may be a property of an overly large membrane enveloped entity), then you can make a reproducing system. Those systems that do well at dividing into two systems (functionally equal to their parent) will persist longer as a reproducing population.

Therefore, naturally arising systems are selected for being autopoietic, or for being able to reproduce (which is a derivative property of being autopoietic). For most biological systems the ultimate goal is to stay alive (be autopoietic) and reproduce. This is the goal that selection has imposed on these systems, because those systems are the ones that end up being around for long periods of time (thus being biologically successful).

The boundary issue comes from the structure of cells, which many would agree are systems.
Is everything inside a cell functionally involved in its success?
I would say yes, but some could argue no.

In biology, interesting situations can arise:

• Parasites can be in the cell, using its resources for its own goals rather than those of the host system. Are they part of the system. Maybe this would be like a computer virus.
• Pathogenic components could be present that are destructive to the operations of the system without favoring its own needs.
• Components that are neither beneficial nor deleterious, just kind of neutral.

Since I am interested in how living systems originated, I want to understand the new formation of chemical systems from non-living systems. That's called abiogenesis.

A big step in the process is forming vesicles that contain a bunch of locally derived chemicals. Vesicles are hydrophobic membranes that envelope a packet of hydrophilic chemicals.
The packet of enveloped chemicals along with the those that make up the membrane can be considered a set (This may be the best approach for me), or they could be considered an incipient system that could either work (be autopoietic) or not. If not they would go away (degenerate chemically, or be negatively selected from population biology point of view).

"Lucky" vesicles would be able to achieve autopoiesis and divide ("live long and prosper").
They may have varying amounts of non-productive components, in addition to those actually doing the business of being autopoietic.

As the systems evolve and become more sophisticated, I would guess they would have a higher proportion of useful components and fewer of the neutral or pathogenic ones. Parasites, however, may be different, since selection on them will favor them if they can successful use the host's resources.

Would this best be considered as a poorly functioning system, that could possibly become more efifcient?
Or a set of randomly selected (chemicals by the making the vesicle process) that might form a functional system, or not. There the componets of the vesicle set could transition to being part of the chemical system with the goal of persisting and reproducing.

I think there are these two approaches:

1. a set which has components a subset of which may form a autopoietic chemical system, or
2. a bounded system of chemicals that might have a lot of chemicals not involved in the system's function. The systems may be barely successful at first, but by changes in its components, could become more efficient.

I would like a way to best deal with the abiogenic-like transition to the autopoietic system from a non-autopoietic system or the set of chemicals from which an autopoietic system could assemble.