# necessary (obligation)

required for a change to happen

- Computed level: L7 (depth in the emergence graph, not abstraction)
- Status: review  ·  Domain: adjective  ·  Arena: lexicon

## Emergence
**Emerges from:** [required](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-required.obligation), [change](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-change.process), [happen](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-happen.event-occurrence)

**Through:** required and change together create a condition that the change cannot occur without it

**Novel properties:**
- dependency for change
- temporal necessity
- unavoidable condition

## Examples
- The International Space Station requires regular reboosts to counteract atmospheric drag and maintain orbit. *(engineering)*
- Cyanobacteria had to evolve oxygenic photosynthesis for Earth's atmosphere to shift from anoxic to oxic 2.4 billion years ago. *(biology)*
- Bitcoin mining consumes more electricity than Argentina annually to secure transaction validation on the blockchain. *(computing)*

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*Canonical: https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-necessary.obligation*  
*Structured data: https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-necessary.obligation.json*  
*Every definition provably resolves to space, time, energy and pattern.*