Complexity and systems thinking

I thought this was a really good high level introduction to how to approach modelling complex systems. The "systems reductionism" idea seems particularly useful to me.

A new proposal by an interdisciplinary team of researchers .. [proposes] nothing less than a new law of nature, according to which the complexity of entities in the universe increases over time with an inexorability comparable to the second law of thermodynamics — the law that dictates an inevitable rise in entropy, a measure of disorder. If they’re right, complex and intelligent life should be widespread.

Complexity economics is a heterodox alternative to neoclassical and mainstream economics, that starts with an assumption of complex system dynamics, and attempts to model economic system behaviour from that.

From the page:

Complexity economics is the application of complexity science to the problems of economics. It relaxes several common assumptions in economics, including general equilibrium theory. While it does not reject the existence of an equilibrium, it features a non-equilibrium approach and sees such equilibria as a special case and as an emergent property resulting from complex interactions between economic agents. The complexity science approach has also been applied to computational economics.

Good simple introduction to an early computer simulation showing complex emergent behaviour from simple rules.

This paper is an excellent overview of the history of systems thinking from mid 20th century onward. It covers 4 waves of systems thinking, and DSRP.

The four waves, roughly summarised are:

• First wave: systems as real-world things - system dynamics, physical science focus
• Second wave: systems as mental models - this wave was more social-science driven
• Third wave: critical systems thinking - bringing critical theory to systems thinking, focused on critique of boundary definitions, and on power in relationships
• Fourth wave: universalisation - trying to pull all the threads together from diverse approaches (this wave is starting, may not happen)

The authors suggest that DSRP is a potential core framework for the fourth wave. DSRP summarised:

• 4 structures, each made of 2 elements, mutually defining
  • A Distinction (D) is defined as identity (i) co-implying an other (o)
  • A System (S) is defined as part (p) co-implying a whole (w)
  • A Relationship (R) is defined as action (a) co-implying a reaction (r)
  • A Perspective (P) is defined as point (ṗ) co-implying a view (v)
  • My understanding is that the first two structures both define the boundaries of the system as a whole, and of the individual components of a system (e.g. actors).
  • DSRP kind of assumes that all system components are also entire systems within themselves (e.g. humans are actors in a social system, but a human is also a system of cells, etc.)
• M = I ⊗ T
  • a mental model (M) is the complex product (⊗) of information (I) and DSRP simple structural rules of thinking (T) (listed above)
• Four levels of depth of abstraction:
  • Atomic Structures: The universal components that can't be broken down further.
    • These are the 4x2 component structures of DSRP, listed above.
  • Molecular structures, or “jigs” or “moves”: Abstractions of mental models.
    • “Jig” as in a work-tool that helps you build something. “Move” as in martial arts or dancing - patterns that repeatedly appear.
    • These are thinking-patterns that are basically information-less models. Often these can be discovered by abstracting from the next level (conceptual models).
    • Examples: 2x2 table of considerations - this appears in lots of types of thinking.
    • There’s a big list at https://help.cabreraresearch.org/moves-glossary
  • Compound structures: Conceptual models that include molecular structures AND information.
    • e.g. any applied model. Traffic optimisation models. SWOT analysis (this is a specific example of a 2x2 table)
  • Any person, any system:
    • They claim this represents all knowledge, but I think it only represents all thinking (maybe).

This paper is an excellent overview of the history of systems thinking from mid 20th century onward. It covers 4 waves of systems thinking, and DSRP.

The four waves, roughly summarised are:

• First wave: systems as real-world things - system dynamics, physical science focus
• Second wave: systems as mental models - this wave was more social-science driven
• Third wave: critical systems thinking - bringing critical theory to systems thinking, focused on critique of boundary definitions, and on power in relationships
• Fourth wave: universalisation - trying to pull all the threads together from diverse approaches (this wave is starting, may not happen)

The authors suggest that DSRP is a potential core framework for the fourth wave. DSRP summarised:

• 4 structures, each made of 2 elements, mutually defining
  • A Distinction (D) is defined as identity (i) co-implying an other (o)
  • A System (S) is defined as part (p) co-implying a whole (w)
  • A Relationship (R) is defined as action (a) co-implying a reaction (r)
  • A Perspective (P) is defined as point (ṗ) co-implying a view (v)
  • My understanding is that the first two structures both define the boundaries of the system as a whole, and of the individual components of a system (e.g. actors).
  • DSRP kind of assumes that all system components are also entire systems within themselves (e.g. humans are actors in a social system, but a human is also a system of cells, etc.)
• M = I ⊗ T
  • a mental model (M) is the complex product (⊗) of information (I) and DSRP simple structural rules of thinking (T) (listed above)
• Four levels of depth of abstraction:
  • Atomic Structures: The universal components that can't be broken down further.
    • These are the 4x2 component structures of DSRP, listed above.
  • Molecular structures, or “jigs” or “moves”: Abstractions of mental models.
    • “Jig” as in a work-tool that helps you build something. “Move” as in martial arts or dancing - patterns that repeatedly appear.
    • These are thinking-patterns that are basically information-less models. Often these can be discovered by abstracting from the next level (conceptual models).
    • Examples: 2x2 table of considerations - this appears in lots of types of thinking.
    • There’s a big list at https://help.cabreraresearch.org/moves-glossary
  • Compound structures: Conceptual models that include molecular structures AND information.
    • e.g. any applied model. Traffic optimisation models. SWOT analysis (this is a specific example of a 2x2 table)
  • Any person, any system:
    • They claim this represents all knowledge, but I think it only represents all thinking (maybe).

This is an excellent introduction to system dynamics style system thinking.