System

• a system has 3 properties:
  • is a set of 2 or more parts and their relations between them
  • none of the parts have an independent effect on the whole (how any part affects the whole, depends on what other parts are doing)
  • between any 2 parts of a system, there is either a direct or indirect path
• a system as a whole cannot be divided into 2 independent parts
• a system is a product of the interaction of parts, not the sum of the parts

Complex System

• a complex system is a special class of system
• 2 criteria of a complex system:
  • high structural diversity (heterogenous) -
  • high organization -
• other criteria of a complex system
  • numerosity - composed of many parts
  • heterogeneous -  the whole is composed of different parts
  • non-linearity - the whole is not always equal to the sum of its parts but more often a product of its parts
  • connectivity - the property of the whole is not based on the property of parts but the structure of the connected parts (e.g. emergent property)
  • autonomy - parts have a degree of autonomy (there is no centralized top-down mechanism for coordinating the whole)
  • feedback loops - the whole is sensitive to initial conditions leading to a large systemic effect (basis of chaos theory). this property is seen over time
  • adaptation -

The Irony of Complexity

• complexity simplifies
• elaboration of structure and control simplifies and channels said system

System Examples

high structural diversity, low organization

US military landed 500,000 types of artifacts at Casablanca in 1942. Great structural diversity. But transport ships loaded with poor organization. “Guns arrived on the beach with no gunsights; guns arrived with no ammunition; guns arrived with no gunners”

low structural diversity, high organization

Subpages

• Complex Adaptive Systems

Resources

• https://en.wikipedia.org/wiki/Complex_system