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The SiD Definition of Sustainability

In this step, we get to finally provide the SID definition of sustainability.
A Fridays for the Future protest cardboard sign reading - Ask not what your planet can do for you. Ask what you can do for your planet.
© Tom Bosschaert, Symbiosis in Development - Making New Futures Possible, 2010-2019
Below, you find the definition of sustainability according to the SiD framework.

Sustainability is the state of a complex, dynamic system. In this state, a system can continue to flourish resiliently, in harmony, without requiring inputs from outside its system boundaries.

Applied to our civilization, this state is consistent with societies powered by renewable energy and closed-loop material systems, inhabiting thriving ecosystems, on a biodiverse planet, with healthy and happy individuals living in just, tolerant, and diverse cultures, supported by open and transparent economies.

The first two sentences define what sustainability is in an actionable and testable way. The second part exemplifies what the definition means when applied to our civilization.

The next activities and steps will unravel the first two sentences, discussing the definitions of ‘systems’, ‘state’, what we mean by ‘complex’ and ‘dynamic’, and how do we tell a sustainable system from an unsustainable one.

If you understand why the definition is formulated this way, you’ll grasp the most important lesson in this course.

© Tom Bosschaert, Symbiosis in Development - Making New Futures Possible, 2010-2019
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An Introduction to Systems Thinking for Sustainability: SiD Theory I

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