# Negative feedback
## MicroSim spec
### Parameters (tunable controls)
- `Loop gain` · 0–5 · fraction of output fed back to oppose the input
- `Input level` · 0–100 · commanded reference [[Signal|signal]]
- `Delay` · 0–20 · lag (frames) before feedback acts
### What animates
An output trace settles toward its reference as the feedback damps oscillations.
### Learning objective
Show how negative feedback stabilizes a system and reduces output fluctuations.
## Links (Wikipedia order)
<!-- injected from _registry/childlinks/Negative_feedback.json (2026-07-30T02:09:12Z) -->
`Addition` · `Adrenal_cortex` · `Albedo` · [[Alexander_Bogdanov]] · [[Allenna_Leonard]] · `Allostasis` · `Amplifier` · `Analog-to-digital_converter` · [[Anatol_Rapoport]] · [[Anthony_Wilden]] · `Asymptotic_gain_model` · `Audio_engineer` · `Audio_signal` · `Automatic_gain_control` · `Ballcock` · [[Barbara_J._Grosz]] · `Baroreflex` · `Biochemistry` · `Biofeedback` · [[Biological_system]] · `Biology` · `Blood_pressure` · `Blood_sugar_level` · [[Béla_H._Bánáthy]] · [[C._West_Churchman]] · `Centrifugal_governor` · [[Chaos_theory]] · [[Charles_A._S._Hall]] · `Chemical_equilibrium` · [[Claude_Shannon]] · `Cloud_cover` · [[Complex_system]] · [[Control_engineering]] · [[Control_theory]] · `Corticotropin-releasing_hormone` · `Cortisol` · `Counterregulatory_hormone` · [[Coupled_human–environment_system]] · `Ctesibius` · [[Cybernetics]] · `Cybernetics:_Or_Control_and_Communication_in_the_Animal_and_the_Machine` · `Dashpot` · `Delta-sigma_modulation` · `Demand` · `Derivative` · [[Distortion]] · [[Donella_Meadows]] · [[Doubling_time]] · [[Earth_system_science]] · `Ecological_economics` · `Economic_system` · [[Ecosystem]] · [[Edsger_W._Dijkstra]] · [[Edward_Norton_Lorenz]] · `Effects_of_climate_change` · [[Emergence]] · [[Engineering]] · [[Eric_Trist]] · `Erythropoiesis` · `Exponential_growth` · `FM_broadcasting` · [[Feedback]] · [[Francisco_Varela]] · `Fred_Emery_(psychologist)` · `Frequency_divider` · `Frequency_multiplier` · [[Frequency_response]] · `Fuel_injection` · [[George_Dantzig]] · [[George_Klir]] · `George_Soros` · `Glucocorticoid` · `Glucose` · `Governor_(device)` · [[Gregory_Bateson]] · `Harold_Stephen_Black` · `Harry_Nyquist` · [[Heinz_von_Foerster]] · `Herman_Daly` · `Heterodox_economics` · [[Homeostasis]] · `Hormone` · [[Howard_T._Odum]] · `Human_anatomy` · [[Humberto_Maturana]] · `Hypothalamus` · [[Ilya_Prigogine]] · [[Information_system]] · `Instability` · `Integral` · `Invisible_hand` · `James_Clerk_Maxwell` · [[James_Grier_Miller]] · [[James_J._Kay]] · `James_Watt` · [[Jay_Wright_Forrester]] · [[Jennifer_Wilby]] · [[John_Seddon]] · `Karl_Küpfmüller` · [[Kathleen_Carley]] · [[Katia_Sycara]] · `Kenneth_E._Boulding` · [[Kevin_Warwick]] · `Le_Chatelier's_principle` · [[Limiting_factor]] · [[List_of_systems_sciences_organizations]] · `List_of_systems_scientists` · `List_of_types_of_equilibrium` · [[Living_systems]] · `Logarithm` · [[Ludwig_von_Bertalanffy]] · [[Lydia_Kavraki]] · `Mainstream_economics` · [[Manfred_Clynes]] · [[Manuela_M._Veloso]] · [[Margaret_Boden]] · [[Margaret_Mead]] · [[Mary_Cartwright]] · `Mathematics` · [[Mechanical_engineering]] · `Mechanical_equilibrium` · `Mechanics` · [[Mihajlo_D._Mesarovic]] · `Mike_Jackson_(systems_scientist)` · `Millstone` · [[Multi-agent_system]] · [[Murray_Bowen]] · `Negative-feedback_amplifier` · [[Nervous_system]] · [[Niklas_Luhmann]] · [[Norbert_Wiener]] · `Nyquist_stability_criterion` · `Open-loop_controller` · `Operational_amplifier` · `Operational_amplifier_applications` · [[Oscillation]] · [[PID_controller]] · [[Perceptual_control_theory]] · `Performance_appraisal` · [[Peter_Senge]] · `Physiology` · `Pituitary_gland` · [[Positive_feedback]] · `Pressure_regulator` · [[Principia_Cybernetica]] · `Process_variable` · `Propagation_delay` · [[Qian_Xuesen]] · [[Quantization_(signal_processing)]] · [[Radhika_Nagpal]] · [[Recommender_system]] · `Regenerative_circuit` · `Regulator_(automatic_control)` · `Reinforcement` · `Reversible_reaction` · `Richard_L._Hills` · `Russell_L._Ackoff` · `Ruzena_Bajcsy` · [[Self-organization]] · [[Sensor]] · `Servomechanism` · `Setpoint_(control_system)` · `Social_system` · [[Sociotechnical_system]] · `Solar_irradiance` · `Sound` · `Sound_quality` · `Speed` · `Stability_criterion` · `Stability_theory` · [[Stafford_Beer]] · `Steady-state_economy` · `Steam_engine` · `Steering_engine` · `Step_response` · [[Stephanie_Forrest]] · `Subtraction` · `Supply_(economics)` · `Supply_and_demand` · [[System]] · [[System_dynamics]] · `Systemics` · `Systems_analysis` · `Systems_art` · [[Systems_biology]] · [[Systems_ecology]] · [[Systems_engineering]] · [[Systems_neuroscience]] · [[Systems_pharmacology]] · `Systems_philosophy` · `Systems_psychology` · [[Systems_science]] · [[Systems_theory]] · `Systems_theory_in_anthropology` · [[Systems_theory_in_archaeology]] · [[Systems_theory_in_political_science]] · [[Systems_thinking]] · [[Talcott_Parsons]] · `Thermostat` · [[Twelve_leverage_points]] · [[Urban_metabolism]] · `Valence_(psychology)` · `Victor_Aladjev` · `Voltage_divider` · `Water_clock` · `Water_cycle` · `Water_vapor` · `Waveform` · `Windmill` · `World-systems_theory`
## From the Real GENERATIVE library
*Negative feedback — placed from the Real G.E.N.E.R.A.T.I.V.E. course library (Engineering room). Source: Wikimedia Commons (via Wikipedia article media). [Details & license](https://commons.wikimedia.org/wiki/File:Ideal_feedback_model.svg).*
*Animated: Negative feedback — placed from the Real G.E.N.E.R.A.T.I.V.E. course library (Engineering room). Source: Wikimedia Commons (via Wikipedia article media). [Details & license](https://commons.wikimedia.org/wiki/File:Negative_Feedback_Gif.gif).*
> Negative feedback (or balancing feedback) occurs when some function of the output of a system, process, or mechanism is fed back in a manner that tends to reduce the fluctuations in the output, whether caused by changes in the input or by other disturbances. A classic example of negative feedback is a heating system thermostat — when the temperature gets hig ([Wikipedia](https://en.wikipedia.org/wiki/Negative_feedback))
<!-- REAL-GENERATIVE-MEDIA:END -->
> p5.js MicroSim stub · part of Systems Engineering · [Wikipedia source](https://en.wikipedia.org/wiki/Negative_feedback)
## Concept summary
Negative feedback (or balancing [[Feedback|feedback]]) occurs when some function of the output of a [[System|system]], process, or mechanism is fed back in a manner that tends to reduce the fluctuations in the output, whether caused by changes in the input or by other disturbances.
## Build checklist
- [ ] Claim it: set `status: in-progress` + `lease` + `leased_at`
- [ ] Write the child page explaining the concept (tie it back to Systems Engineering)
- [ ] Finalize parameter ranges and defaults
- [ ] Implement the p5.js sketch (drawing + control regions)
- [ ] Add caption + the learning objective on the page
- [ ] Set `status: done`
## p5.js sketch
```javascript
// MicroSim: Negative feedback
const ARTICLE = "Negative_feedback";
let p1, p2, p3;
function setup() {
createCanvas(720, 520);
pixelDensity(2);
// feedback-loop sim — create the three sliders described above:
// Loop gain (0–5), Input level (0–100), Delay (0–20).
// TODO: build labelled sliders in the control region (below the drawing region).
}
function draw() {
background(248);
// TODO: read p1/p2/p3; render the feedback-loop in the drawing region and respond live.
// TODO: HUD — title + en.wikitube.io/wiki/Negative_feedback + control hints + live readouts.
}
```
---
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## Semiotic profile
> *The semiotic universals this article invokes, machine-derived from the crossref — **unverified** (born so). Populated 2026-07-06 for the Systems room.*
**Universals (6):** 🟢 feedback (56) · 🟡 system (29) · 🟡 science (5) · 🟢 signal (4) · 🟢 oscillation (2) · 🟢 equilibrium (2)
**Enter by sign:** Systems Semiotic Gateway · Alphabetum · Icon Registry · ← Systems Portal
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## Wikipedia : Wikitube
**Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Negative_feedback) : [Wikitube](https://en.wikitube.io/wiki/Negative_feedback)
## Previous hub tags
Tree parents: [[Causal_loop_diagram]] · [[Control_theory]] · [[Cybernetics]] · [[Feedback]] · [[Operations_research]] · [[Reliability_engineering]] · [[Self-organization]] · [[System_dynamics]] · [[Systems_engineering]] · [[Systems_science]] · [[Systems_theory]].
Legacy hubs: none.
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*Sources: 4 legacy notes. Minted wave 1, 2026-07-30 (v1.6 order).*