# viable (functional)

a parameter whose drift is moving toward the center of its window

- Computed level: L15 (depth in the emergence graph, not abstraction)
- Status: review  ·  Domain: emergence  ·  Arena: general

## Emergence
**Emerges from:** [parameter](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-parameter.condition), [drift](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-drift.aimless), [window](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-window.range), [center](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-center.location), [motion](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-motion.movement), [toward](https://emergencemachine.com/tools/lexicon/what-is-the-meaning-of-toward.spatial)

**Through:** drift.aimless moves the parameter.condition through window.range toward center.location, guided by motion.movement and the directional sense of toward.spatial.

**Novel properties:**
- directed drift
- central tendency
- functional resilience

## Examples
- The International Space Station's orbit decays but is periodically boosted back to 400 km altitude. *(engineering)*
- In 2023, the Federal Reserve raised interest rates to push inflation toward its 2% target. *(economics)*
- A neuron's membrane potential returns to -70 mV after firing, guided by ion pumps. *(biology)*

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