> [!tldr] Emergence
> the principle that entities exhibit properties which are meaningfully only when attributed to the whole, not to its parts
> [[Systems Engineering Book of Knowledge|SEBoK]] pg153
A great evocative example of emergence:
> [!cite] Bird example 🦅
> Feathers, beaks, wings, and gullets do not have the ability to overcome gravity; however, when they are properly connected to a bird, the create the emergent behavior of flight.
>
> [[Systems Engineering Book of Knowledge|SEBoK]] pg153
Emergence is a **macro-level** property of systems, in particular [[System Complexity|complex systems]]. It's a [[Pattern]] of systems behavior, and one of the benefits behind using [[Systems Thinking]].
Emergence is ultimately what we're going for when we create systems. The types of emergence we "expect" and design the system to accomplish are called _simple emergence_. There are, however, often (or always) _unexpected_ emergences, called **strong emergence**. These can be difficult-to-impossible to predict and can be catastrophic. [[Iteration is the Only Effective Method of Controlling Emergence]].
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# More
## Source
- [[Systems Engineering Book of Knowledge]]
## Related
- [[System Complexity]]
- [[Systems Engineering]]
- [[Low-Cost Trials]]
- [[Plan for Failure]]