This document discusses systems thinking and its application to systems and systems of systems. It defines key properties of systems, including that they have multiple interacting parts and emergent properties. It also discusses different types of systems classification and perspectives in systems thinking. The document emphasizes that systems of systems are composed of independent systems that can provide value on their own but come together for higher-level function, resulting in emergent properties.

1. Systems Thinking in the Circular
Economy
UCL Centre for Systems Engineering
Raúl Leal

2. UCL CENTRE FOR SYSTEMS ENGINEERING
Systems:
Essential properties
1. An ‘architect’/observer – to conceptualise the system, which
must have:
2. Multiple (more than one) parts
3. Interactions between the parts
4. At least one emergent property
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3. UCL CENTRE FOR SYSTEMS ENGINEERING
System properties:
‘Architect’ (or architecting logic or generative philosophy)
Observer (or observer’s logic or conceptual model)
• The definition of a system is subjective
• Different ‘logics’ could promote different things in the
same group of objects and characterise them in many
different ways:
– One may emphasise aesthetics
– One may be interested in thermodynamic or mechanical factors
– One may concentrate in software or hardware
– One may consider only the humans that interact in/with the system
– Others may include a particular set of values or beliefs
Ultimately, the ‘architect’/observer defines a system in a way that will
be useful 3

4. UCL CENTRE FOR SYSTEMS ENGINEERING
Multiple parts:
Parts with life
• But the entities inside may
have a life of their own
• They may be dynamic,
evolving, disruptive, failing,
driving, etc.
• The parts make up the whole
as much as the whole make up
the parts. From this we find the
need to continuously question
the ‘boundary’
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5. UCL CENTRE FOR SYSTEMS ENGINEERING
System properties:
Interactions between parts
• A collection of parts that do not interact does not constitute
a system
• What constitutes an interaction?
– Information flow, physical contact, policy, heat flow, conversations,
emails, gravitational force, electromagnetic radiation, hand and facial
gestures, silence, political decisions, standards?
• It is not possible to conceive a collection of parts that do
not interact in any way but we need to decide what parts
and what interactions are relevant
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6. UCL CENTRE FOR SYSTEMS ENGINEERING
System properties:
Emergent properties
• Systems must have at least one
emergent property
• The whole must be more than the
sum of the parts
• Emergent properties are derived
from the interactions between the
parts of the system as defined
H
H
O
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7. UCL CENTRE FOR SYSTEMS ENGINEERING
Systems Thinking:
The whole is, potentially, unknowable
• The whole is not unique and due to its recursive and
dynamic nature, impossible to characterise completely a
priori. The whole is not totalitarian.
• Consider the following possibilities:
– The parts are sometimes greater than the whole (when a part is an
extraordinary driving force)
– The collection of parts are sometimes less than the sum of the parts (due to
inhibiting factors)
– The whole contains uncertainty (degradations, partial/whole failures, chaos,
conflict) and therefore, non deterministic
• Therefore, holism doesn’t lead to an absolute
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8. UCL CENTRE FOR SYSTEMS ENGINEERING
Ways of classifying systems
• Low Integration or High Integration?
• Hard or Soft?
• Closed or Open?
• Conceptual or Practical?
• Static or Dynamic?
• Deterministic or Probabilistic?
• Linear or Non-linear?
• The most difficult to understand are Complex Systems which are Highly
Integrated, Soft, Open, Practical, Dynamic, Probabilistic and Non-linear
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9. UCL CENTRE FOR SYSTEMS ENGINEERING
Systems Thinking
Perspectives
• Seeing the world in terms of the organization and connection between
underlying objects or components
• Exploring the implications of connectedness, through the concepts of:
– Holism and ‘cause and effect thinking’
– Hierarchy
– Partitioning
– Lifecycles
– Subjectivity
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10. UCL CENTRE FOR SYSTEMS ENGINEERING
What is System of Systems?
What makes it different?

11. UCL CENTRE FOR SYSTEMS ENGINEERING
Systems of systems
• A SoS is an integration of a finite number of constituent systems which are
independent and operatable, and which are networked together for a period
of time to achieve a certain higher goal. (Jamshidi 2009)
• An SoS (Maier, 1998) will have:
– Operational independence of constituent systems
– Managerial independence of constituent systems
– Geographical distribution
– Emergent behavior
– Evolutionary development processes.
Made up of Systems that can function and add value in their own right.
When brought together they can create even more value – a property of
emergence from the SoS.
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12. UCL CENTRE FOR SYSTEMS ENGINEERING
What is special about a System of Systems?
SoS conditions for understanding (and
management?)

13. UCL CENTRE FOR SYSTEMS ENGINEERING
SoS Architecting
System Abstractions
Operational:
How will it be
used?
Functional:
What will it
do?
Enterprise:
What is its
purpose,
context and
need
Performance:
How well will it
do it?
Logical:
How will it
work?
Physical:
What is it?

14. UCL CENTRE FOR SYSTEMS ENGINEERING
SoS and Architectural Frameworks
Different Viewpoints
SystemSystem
Customer
View
Customer
View
Organisational
View
Organisational
View
Operational
View
Operational
View
Technical
View
Technical
View
Environmental
View
Environmental
View
• Different ways of looking at
and describing the system
• Each is an architectural
viewpoint
• How do we know what
views we need and how do
we organise them?

15. UCL CENTRE FOR SYSTEMS ENGINEERING
Dynamics and Interdependency
• Use systems dynamics
modelling to investigate,
map and understand
systems connections,
interdependencies,
strength of interactions,
delays and leverage
points.
• Use systems dynamics
to highlight how agents
outside conventional
mechanisms can be key
enablers of and barriers
to change

16. The
Circular Economy
in the
Asia Pacific Region
www.circularecconomyasia.org